• Biology

    The study of life

  • Cells

  • Movement of Substance

  • Nutrients

  • Enzymes

  • Human Nutrition

  • Plant Nutrition

  • Organelle Functions

  • Comparison

  • Specialised Cells

  • Diffusion

  • Osmosis

  • Active Transport

  • Water

  • Carbohydrates

  • Proteins

  • Lipids

  • Organs

  • Liver

  • Zoom in

  • Leaf Structure

  • Photosynthesis

  • #Limiting Factors

    • Light intensity
    • Carbon dioxide concentration
    • Temperature
  • Chloroplast

    Site of photosynthesis

  • Cell Surface Membrane

    • Retains cellular contents
    • Forms permeability barrier between cytoplasm and extracellular environment
    • Controls the movement of substances
    • Enables cell to respond to extracellular signals
    • Enables cell to communicate with other cells
  • Cell Wall

    • Mechanical protection from injury
    • Gives plant cell a fixed shape
  • Cytoplasm

    • Where most cell activities occur
    • Transport materials within cell
  • Cell Vacuoles

    Store substances within the cell
    Maintains turgor pressure (plant cell)

  • Nucleus

    • Important for cell division
    • Controls cellular activities
    • Contains genetic information
  • Smooth Endoplasmic Reticulum

    • Synthesis of lipids and steroids
    • Detoxification
  • Rough Endoplasmic Reticulum

    Membrane protein synthesis

  • Mitochondria

    Site of aerobic respiration

  • Golgi Apparatus

    • Chemical modification of proteins
    • Sorting, packaging and secretion of proteins
    • Lysosome formation
  • Ribosomes

    Site of protein synthesis

  • Plant vs Animal

    Chloroplast & cell wall in plants only
    Centrioles in animals only
    Central vacuole in plants, small temporary vacuoles in animals

  • Cells, Tissue, Organ, Organ System

  • Xylem Cells

    Conduction and support

  • Root hair cells

    Absorption of water and mineral salts

  • Red blood cells

    Transport of oxygen

  • Definition

    The net movement of substances from a region of higher concentration to a region of lower concentration down the concentration gradient

  • Role

    • Nutrient uptake
    • Gaseous exchange
  • Definition

    The net movement of water molecules from a region of higher water potential to a region of lower water potential through a partially permeable membrane down a water potential gradient

  • Effects

    Hypotonic: Higher water potential
    Hypertonic: Lower water potential
    Isotonic: Same Water Potential

  • Definition

    The movement of substances from a region of lower concentration to a region of higher concentration through a partially permeable membrane against the concentration gradient via a membrane-bound pump by using energy

  • Importance

    • Ion uptake by root hairs and
    • Uptake of glucose by cells in the villi
  • Roles

    • Major component of protoplasm
    • Medium for chemical reactions
    • Transport agent
    • Essential component of body fluids
    • Regulates body temperature by using sweat
  • Info

  • Roles

    • Substrates for respiration
    • Structural carbohydrates
    • Convert to other organic compounds
    • Formation of nucleic acids
    • Synthesis of lubricants
    • Synthesis of nectar
  • Starch Test

    Iodine Test

    Add a few drops of iodine solution

  • Reducing Sugars Test

    Benedict’s Test

  • Info

  • Types

    • Amino acids
    • Polypeptides
    • Protein
  • Roles

    • Synthesis of new protoplasm for growth & repair
    • Synthesis of enzymes & some hormones
    • Formation of antibodies to combat diseases
  • Protein Test

    Biuret Test

  • Info

  • Roles

    • Source of energy
    • Insulation
    • Transport agent for some vitamins and vital substances
    • Component of cell surface membrane
    • Prevents water loss
  • Fats Test

    Ethanol-emulsion Test

  • Mouth

  • Oesophagus

     Narrow, muscular tube that joins the pharynx and the stomach uses peristalsis to push food forward

  • Stomach

  • Small Intestine

  • Gall Bladder

    Stores bile produced by the liver which emulsifies fats increasing the surface area to volume ratio

  • Pancreas

  • Large Intestine

  • Liver Vessels

  • Functions

    • Deamination
    • Detoxification
    • Regulation of Blood Glucose Concentration
    • Protein synthesis
    • Bile production
    • Iron storage
  • Effects of Alcohol

    • Depressant
    • Reduced self-control
    • Slower reaction time
    • Excessive stomach acid secreted
    • Replaces liver cells with fibrous tissue by cirrhosis
    • Social Implications
  • Peristalsis

    The rhythmic wave-like antagonistic contraction and relaxation of smooth muscle layers, outer longitudinal muscles and inner circular muscles, causing dilation and constriction to mix and propel food

  • Villi

    Increase surface area to volume ratio

  • External

  • Internal

  • Adaptations

    • Petiole
    • Thin lamina
    • Large flat surface
    • Waxy cuticle on upper and lower epidermal layers
    • Stomata present mostly in lower epidermis
    • Chloroplasts containing chlorophyll
    • More chloroplasts in upper palisade tissue
    • Inter-connecting system of air spaces in mesophyll
    • Veins containing xylem and phloem
  • Requirements

    • Carbon Dioxide
    • Water
  • Products

    • Glucose
    • Oxygen
    • Water (Optional)
  • Chemical Equations

    • Cell

      Smallest unit of life

    • Tissue

      A group of cells which work together to perform a specific function

    • Organ

      Different tissues working together to perform specific function

    • System

      Several organs working together for common purpose form system

    • Long Hollow Tubes with No Cross Walls/Protoplasm

      Create a continuously empty lumen

    • Narrow lumen

      Transport of water by capillary actions

    • Ligin deposited on the walls

      • Waterproof to prevent loss of water
      • Strong to provide mechanical support and prevents collapse.
    • Long and Narrow Extension

      Increases surface area to volume ratio of the cell which allows water and mineral salts to be more efficiently absorbed

    • Rich in mitochondria

      Active transport of mineral salt against the concentration gradient into root hair cell

    • Presence of Haemoglobin

      Contains red pigment called haemoglobin which transports oxygen from lungs to all parts of body

    • No Nucleus

      Allows it to carry more haemoglobin ∴ more oxygen

    • Circular Biconcave Shape

      Increases surface area to volume ratio for faster oxygen diffusion

    • Flexible Cell Surface Membrane

      Allows red blood cells to squeeze through fine capillaries

    • Animal

    • Plant

    • Elements

      C, H, O
      H:O = 2:1

    • Types

    • Results

      Blue-black: √
      Yellow: X

    • Sucrose

      1. Add 4 drops of hydrochloric acid
      2. Boil for 2-3 minutes
      3. Let it cool
      4. Add sodium hydrogen carbonate to neutralise the acid

      Go to solid/liquid

    • Solid

      1. Cut up into smaller pieces
      2. Add 2cm3 of water
      3. Stir
      4. Decant the water

      Go to liquid step 2

    • Liquid

      1. Add 2cm3 of the food sample
      2. Add 2cm3 of Benedict’s solution
      3. Boil for 2-3 minutes
    • Elements

      C, H, O, N (Sometimes S)

    • Solid

      1. Cut up into smaller pieces
      2. Add 2cm3 of water
      3. Stir
      4. Decant the water

      Go to liquid step 2

    • Liquid

      1. Add 2cm3 food sample
      2. Add 2cm3 of Biuret solution
    • Elements

      C, H, O
      H > O

    • Components

      • Fatty acids
      • Glycerol
    • Solid

      1. Cut up the food into smaller pieces
      2. Add 2cm3 of ethanol
      3. Shake thoroughly
      4. Decant to 2cm3 of water
    • Liquid

      1. Add 2cm3 of food sample
      2. Add 2cm3 of ethanol
      3. Shake thoroughly
      4. Add 2cm3 of water
    • Results
      Cloudy white emulsion: √
      Clear: X

    • Salivary glands

      Produce and secrete saliva the mouth

    • Buccal cavity

      Space enclosed by the mouth

    • Teeth

       Chewing action breaks up food into small pieces (mastication) to increase surface area to volume ratio for digestive enzyme action

    • Tongue

       Rolls food and saliva into small masses (boli) to facilitate swallowing

    • Distensible, muscular bag

       Stretches when temporarily storing food, informs the brain when fully-distended

    •  Thick, well-developed muscular wall

      Peristalsis churns the food to mechanically break them up and mix them forming chyme

    •  Wall has numerous pits

      Gastric glands which produce gastric juice which contains hydrochloric acid, pepsin and renin

    • Parts

      • Duodenum (U-shaped)
      • Jejunum
      • Ileum (Much-coiled)
    • Intestinal Juice

      • Maltase
      • Sucrase
      • Lactase
      • Erepsin (Peptidase)
      • Lipase
    • Pancreatic Juice

      • Insulin
      • Glucagon
      • Amylase
      • Trypsin/Chymotrypsin
      • Lipase
      • Nuclease
    • Colon

      •  Absorbs H2O, mineral salts and vitamins from undigested food
      • Peristalsis of colon wall propels undigested food to the rectum
    • Hepatic Portal Vein

      Nutrient-rich blood from small intestine to liver

    •  Hepatic Artery

      Oxygenated blood from heart to liver

    • Hepatic vein

      Deoxygenated blood from the liver to the heart

    •  1-cell thick epithelium

      Smaller diffusion distance, has microvilli to increase surface area to volume ratio

    •  Blood and Lymph Capillaries

      Maintain concentration gradients

    • Network of Veins

      Veins carry water and mineral salts to the cells in the lamina and carry manufactured food from these cells to other parts of the plant

    • Lamina

      The lamina has a large flat surface compared to its volume. This enables it to obtain the maximum amount of sunlight for photosynthesis
      A large, thin lamina also means that carbon dioxide can rapidly reach the inner cells of the leaf

    • Leaf Arrangement

      • Leaves are always organised around the stem in a regular pattern
      • Ensures that the leaves are not blocking one another from the sunlight and that each leaf receives sufficient sunlight
    • Petiole

      The petiole holds the lamina away from the stem so that the lamina can obtain sufficient sunlight and air in come leaves

    • Upper Epidermal Cells

      • Single layer of closely packed cells
      • Covered on the outside by waxy and transparent cuticle.
      • Epidermis protects the inner regions of the leaf
    • Palisade Mesophyll Cells

      • One or two layers of closely packed, long and cylindrical cells with their long axes at right angles to the epidermis
      • Contain numerous chloroplasts
    • Spongy Mesophyll Cells

      • Irregularly shaped cells that are loosely packed with numerous large intercellular air spaces
      • Fewer chloroplasts than palisade mesophyll cells
      • Cells covered with thin moisture film
      • Contain vascular bundle, xylem and phloem
    • Lower Epidermal Cells

      • Single layer of closely packed cells beneath mesophyll
      • Covered by an outer layer of cuticle to reduce water loss
    • Guard Cells

    • Stomata

      Minute openings usually found on the lower epidermis

    • Light-Dependent

      Light energy -> Chemical energy
      12H2O (Photolysis) -> 6O2 + 24H

    • Light-Independent

      6CO2 + 24H (Chemical energy) -> C6H12O6 + 6H2O
      (Enzyme-controlled reactions)

    • Overall

      6CO2 + 12H2O > C6H12O6 + 6O2 + 6H2O

    • Simplified

      6CO2 + 6H2O > C6H12O6 + 6O2
      Carbon dioxide + Water > Glucose + Oxygen

    • Hypotonic

      When an animal cell is placed in a hypotonic solution, water, water enters animal cell by endosmosis. Cytoplasm has lower water potential than external solution, water enters cell by osmosis. Cell expands in volume. Cell membrane is too delicate to prevent further expansion. Cell lyses and cell contents poured out.

    • Hypertonic

      When an animal cell is placed in a hypertonic solution, water leaves the cell by exosmosis. Cytoplasm has higher water potential than external solution, water leaves the cell by osmosis. Cell shrinks in volume. Cell membrane crinkles and forms spikes in a process called crenation. Animal cell eventually dehydrates and dies.

    • Hypotonic

      When a plant cell is placed in a hypotonic solution/water, water enters plant cell by endosmosis. Cell sap has lower water potential than external solution, water moves through cell wall and cell membrane and enters cytoplasm and vacuole by osmosis. Vacuole increases in size. Cell expands in volume. Cytoplasm and cell surface membrane pushed against and exerts pressure on cellulose cell wall. Water stops entering when inelastic cell wall exerts opposing pressure to resist further expansion. Cell becomes turgid.

    • Hypertonic

      When a plant cell is placed in a hypertonic solution, water leaves plant cell by exosmosis. Cell sap has higher water potential than external solution, water leaves vacuole and cytoplasm and moves through cell membrane and cell wall by osmosis. Vacuole and cell shrink in size. Cytoplasm & cell membrane pull away from cell wall in a process known as plasmolysis. Cell becomes flaccid.

    • Monosaccharides

      • Glucose
      • Galactose
      • Fructose
    • Disaccharides

      • Maltose
      • Lactose
      • Sucrose
    • Polysaccharides

      • Starch
      • Cellulose
      • Glucagen
    • Results

      Blue: X
      Brick-red precipitate: √

    • Mucus and water

      • Moistens mouth & tongue and softens food
      • Facilitates swallowing
    • Salivary amylase

      • Breaks down starch into maltose
      • pH 7
         - Optimal for salivary amylase activity
      • Lysozyme
         - Destroys bacteria
    • Hydrochloric Acid

      • Stops salivary amylase activity
      • Activates pepsinogen and prorennin
      • Provides acidic pH optimal for pepsin and rennin activities
      • Denatures proteins in food to exposes peptide bonds for hydrolysis by pepsin
      • Kills germs
    • Pepsin

      Pepsinogen (Inactive) + HCl > Pepsin (Active)
      Protein + Pepsin > Peptides

    • #Rennin
      Prorennin (Inactive) + HCl > Rennin (Active)
      Milk protein caseinogen (Soluble) + Rennin > Casein (Insoluble)
      So it stays longer in the stomach

    • Lined by mucus layer

      Protection against damage by hydrochloric acid in gastric juice

    • Sphincters

      The lower oesophageal sphincter connects stomach to the oesophagus and the pyloric sphincter connects stomach to the small intestine, they control the movement of food into and out of the stomach

    • Blood Capillaries

      Transports glucose and amino acids

    • Lymph Capillaries (Lacteals)

      Transports lipids

    • Day

      • Increase water potential
      • Produce glucose
      • Convert light to chemical energy to be used to pump K+ ions into guard cells from neighbouring epidermal cells by active transport
      • Water from other cells enter the guard cells by osmosis
      • Swell and become turgid
      • Since they have a thicker cellulose wall on one side of the cell, the swollen guard cells move further apart and pull the stoma open
    • Night

      • Lower water potential
      • Sugar is used up
      • K+ ions diffuse out
      • Water leaves the guard cells by osmosis
      • Become flaccid and the stoma closes.
    {"cards":[{"_id":"536a211b4de898da0684d477","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":null,"content":"# Biology\nThe study of life","deleted":false},{"_id":"42257d962b4899ee270000c8","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"536a211b4de898da0684d477","content":"# Cells"},{"_id":"42257f952b4899ee270000ce","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42257d962b4899ee270000c8","content":"# Organelle Functions"},{"_id":"4225819f2b4899ee270000cf","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42257f952b4899ee270000ce","content":"# Chloroplast\nSite of photosynthesis"},{"_id":"4225869ccdba0c06c8000073","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42257f952b4899ee270000ce","content":"# Cell Surface Membrane\n* Retains cellular contents\n* Forms permeability barrier between cytoplasm and extracellular environment\n* Controls the movement of substances\n* Enables cell to respond to extracellular signals\n* Enables cell to communicate with other cells"},{"_id":"42258840cdba0c06c8000074","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42257f952b4899ee270000ce","content":"# Cell Wall\n* Mechanical protection from injury\n* Gives plant cell a fixed shape"},{"_id":"42258906cdba0c06c8000075","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"42257f952b4899ee270000ce","content":"# Cytoplasm\n* Where most cell activities occur\n* Transport materials within cell"},{"_id":"422589b7cdba0c06c8000076","treeId":"536a211b4de898da0684d46e","seq":1,"position":5,"parentId":"42257f952b4899ee270000ce","content":"# Cell Vacuoles\nStore substances within the cell\nMaintains turgor pressure (plant cell)"},{"_id":"42258b71cdba0c06c8000078","treeId":"536a211b4de898da0684d46e","seq":1,"position":6,"parentId":"42257f952b4899ee270000ce","content":"# Nucleus\n* Important for cell division\n* Controls cellular activities\n* Contains genetic information"},{"_id":"42258cd0cdba0c06c8000079","treeId":"536a211b4de898da0684d46e","seq":1,"position":7,"parentId":"42257f952b4899ee270000ce","content":"# Smooth Endoplasmic Reticulum\n* Synthesis of lipids and steroids\n* Detoxification"},{"_id":"42258d7acdba0c06c800007a","treeId":"536a211b4de898da0684d46e","seq":1,"position":8,"parentId":"42257f952b4899ee270000ce","content":"# Rough Endoplasmic Reticulum\nMembrane protein synthesis"},{"_id":"42258e34cdba0c06c800007b","treeId":"536a211b4de898da0684d46e","seq":1,"position":9,"parentId":"42257f952b4899ee270000ce","content":"# Mitochondria\nSite of aerobic respiration"},{"_id":"42258f21cdba0c06c800007c","treeId":"536a211b4de898da0684d46e","seq":1,"position":10,"parentId":"42257f952b4899ee270000ce","content":"# Golgi Apparatus\n* Chemical modification of proteins\n* Sorting, packaging and secretion of proteins\n* Lysosome formation"},{"_id":"42258fd5cdba0c06c800007d","treeId":"536a211b4de898da0684d46e","seq":1,"position":11,"parentId":"42257f952b4899ee270000ce","content":"# Ribosomes\nSite of protein synthesis"},{"_id":"422591a6cdba0c06c800007e","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42257d962b4899ee270000c8","content":"# Comparison"},{"_id":"422591fbcdba0c06c800007f","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"422591a6cdba0c06c800007e","content":"# Plant vs Animal\nChloroplast & cell wall in plants only\nCentrioles in animals only\nCentral vacuole in plants, small temporary vacuoles in animals"},{"_id":"42259587cdba0c06c8000080","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"422591a6cdba0c06c800007e","content":"# Cells, Tissue, Organ, Organ System\n"},{"_id":"4225975acdba0c06c8000081","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42259587cdba0c06c8000080","content":"# Cell\nSmallest unit of life"},{"_id":"4225981ccdba0c06c8000082","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42259587cdba0c06c8000080","content":"# Tissue\nA group of cells which work together to perform a specific function"},{"_id":"422598f2cdba0c06c8000083","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42259587cdba0c06c8000080","content":"# Organ\nDifferent tissues working together to perform specific function"},{"_id":"42259943cdba0c06c8000084","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"42259587cdba0c06c8000080","content":"# System\nSeveral organs working together for common purpose form system"},{"_id":"422599bfcdba0c06c8000085","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42257d962b4899ee270000c8","content":"# Specialised Cells"},{"_id":"42259ae2cdba0c06c8000087","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"422599bfcdba0c06c8000085","content":"# Xylem Cells\nConduction and support"},{"_id":"42259be1cdba0c06c8000088","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42259ae2cdba0c06c8000087","content":"# Long Hollow Tubes with No Cross Walls/Protoplasm\nCreate a continuously empty lumen"},{"_id":"42259d18cdba0c06c8000089","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42259ae2cdba0c06c8000087","content":"# Narrow lumen\nTransport of water by capillary actions"},{"_id":"42259e08cdba0c06c800008a","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42259ae2cdba0c06c8000087","content":"# Ligin deposited on the walls\n* Waterproof to prevent loss of water\n* Strong to provide mechanical support and prevents collapse."},{"_id":"4225a0adcdba0c06c800008b","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"422599bfcdba0c06c8000085","content":"# Root hair cells\nAbsorption of water and mineral salts"},{"_id":"4225a1b9cdba0c06c800008c","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225a0adcdba0c06c800008b","content":"# Long and Narrow Extension\nIncreases surface area to volume ratio of the cell which allows water and mineral salts to be more efficiently absorbed"},{"_id":"4225a266cdba0c06c800008d","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225a0adcdba0c06c800008b","content":"# Rich in mitochondria\nActive transport of mineral salt against the concentration gradient into root hair cell"},{"_id":"4225a292cdba0c06c800008e","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"422599bfcdba0c06c8000085","content":"# Red blood cells\nTransport of oxygen"},{"_id":"4225a330cdba0c06c800008f","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225a292cdba0c06c800008e","content":"# Presence of Haemoglobin\nContains red pigment called haemoglobin which transports oxygen from lungs to all parts of body"},{"_id":"4225a37ccdba0c06c8000090","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225a292cdba0c06c800008e","content":"# No Nucleus\nAllows it to carry more haemoglobin ∴ more oxygen"},{"_id":"4225a451cdba0c06c8000091","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"4225a292cdba0c06c800008e","content":"# Circular Biconcave Shape\nIncreases surface area to volume ratio for faster oxygen diffusion"},{"_id":"4225a46bcdba0c06c8000092","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"4225a292cdba0c06c800008e","content":"# Flexible Cell Surface Membrane\nAllows red blood cells to squeeze through fine capillaries"},{"_id":"42257dfc2b4899ee270000c9","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"536a211b4de898da0684d477","content":"# Movement of Substance"},{"_id":"4225a5a5cdba0c06c8000093","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42257dfc2b4899ee270000c9","content":"# Diffusion"},{"_id":"4225a5e7cdba0c06c8000094","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225a5a5cdba0c06c8000093","content":"# Definition\nThe net movement of substances from a region of higher concentration to a region of lower concentration down the concentration gradient"},{"_id":"4225b95ecdba0c06c8000096","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225a5a5cdba0c06c8000093","content":"# Role\n* Nutrient uptake\n* Gaseous exchange"},{"_id":"4225b739cdba0c06c8000095","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42257dfc2b4899ee270000c9","content":"# Osmosis"},{"_id":"4225ce31cdba0c06c800009e","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225b739cdba0c06c8000095","content":"# Definition\nThe net movement of water molecules from a region of higher water potential to a region of lower water potential through a partially permeable membrane down a water potential gradient"},{"_id":"4225d2cacdba0c06c800009f","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225b739cdba0c06c8000095","content":"# Effects\nHypotonic: Higher water potential\nHypertonic: Lower water potential\nIsotonic: Same Water Potential"},{"_id":"4225e2bbcdba0c06c80000a3","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225d2cacdba0c06c800009f","content":"# Animal"},{"_id":"4225e31dcdba0c06c80000a4","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225e2bbcdba0c06c80000a3","content":"# Hypotonic\nWhen an animal cell is placed in a hypotonic solution, water, water enters animal cell by endosmosis. Cytoplasm has lower water potential than external solution, water enters cell by osmosis. Cell expands in volume. Cell membrane is too delicate to prevent further expansion. Cell lyses and cell contents poured out."},{"_id":"4225e4b7cdba0c06c80000a5","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225e2bbcdba0c06c80000a3","content":"# Hypertonic\nWhen an animal cell is placed in a hypertonic solution, water leaves the cell by exosmosis. Cytoplasm has higher water potential than external solution, water leaves the cell by osmosis. Cell shrinks in volume. Cell membrane crinkles and forms spikes in a process called crenation. Animal cell eventually dehydrates and dies."},{"_id":"4225e539cdba0c06c80000a6","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225d2cacdba0c06c800009f","content":"# Plant"},{"_id":"4225e591cdba0c06c80000a7","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225e539cdba0c06c80000a6","content":"# Hypotonic\nWhen a plant cell is placed in a hypotonic solution/water, water enters plant cell by endosmosis. Cell sap has lower water potential than external solution, water moves through cell wall and cell membrane and enters cytoplasm and vacuole by osmosis. Vacuole increases in size. Cell expands in volume. Cytoplasm and cell surface membrane pushed against and exerts pressure on cellulose cell wall. Water stops entering when inelastic cell wall exerts opposing pressure to resist further expansion. Cell becomes turgid."},{"_id":"4225e641cdba0c06c80000a8","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225e539cdba0c06c80000a6","content":"# Hypertonic\nWhen a plant cell is placed in a hypertonic solution, water leaves plant cell by exosmosis. Cell sap has higher water potential than external solution, water leaves vacuole and cytoplasm and moves through cell membrane and cell wall by osmosis. Vacuole and cell shrink in size. Cytoplasm & cell membrane pull away from cell wall in a process known as plasmolysis. Cell becomes flaccid."},{"_id":"4225d4f0cdba0c06c80000a0","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42257dfc2b4899ee270000c9","content":"# Active Transport"},{"_id":"4225d5cbcdba0c06c80000a1","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225d4f0cdba0c06c80000a0","content":"# Definition\n The movement of substances from a region of lower concentration to a region of higher concentration through a partially permeable membrane against the concentration gradient via a membrane-bound pump by using energy"},{"_id":"4225dda9cdba0c06c80000a2","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225d4f0cdba0c06c80000a0","content":"# Importance\n* Ion uptake by root hairs and\n* Uptake of glucose by cells in the villi"},{"_id":"42257e502b4899ee270000ca","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"536a211b4de898da0684d477","content":"# Nutrients"},{"_id":"4225f2f7cdba0c06c80000a9","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42257e502b4899ee270000ca","content":"# Water"},{"_id":"4226008bcdba0c06c80000ad","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225f2f7cdba0c06c80000a9","content":"# Roles\n* Major component of protoplasm\n* Medium for chemical reactions\n* Transport agent\n* Essential component of body fluids\n* Regulates body temperature by using sweat"},{"_id":"4225fef0cdba0c06c80000aa","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42257e502b4899ee270000ca","content":"# Carbohydrates"},{"_id":"42260e67cdba0c06c80000ae","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225fef0cdba0c06c80000aa","content":"# Info"},{"_id":"422616c3cdba0c06c80000af","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42260e67cdba0c06c80000ae","content":"# Elements\nC, H, O\nH:O = 2:1"},{"_id":"42261719cdba0c06c80000b0","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42260e67cdba0c06c80000ae","content":"# Types"},{"_id":"4226177ecdba0c06c80000b1","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42261719cdba0c06c80000b0","content":"# Monosaccharides\n* Glucose\n* Galactose\n* Fructose"},{"_id":"4226180acdba0c06c80000b2","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42261719cdba0c06c80000b0","content":"# Disaccharides\n* Maltose\n* Lactose\n* Sucrose"},{"_id":"4226402b751b80bd1e00004d","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42261719cdba0c06c80000b0","content":"# Polysaccharides\n* Starch\n* Cellulose\n* Glucagen"},{"_id":"4226743a751b80bd1e00004e","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225fef0cdba0c06c80000aa","content":"# Roles\n* Substrates for respiration\n* Structural carbohydrates\n* Convert to other organic compounds\n* Formation of nucleic acids\n* Synthesis of lubricants\n* Synthesis of nectar"},{"_id":"42268d8d1aba1d5f8400004f","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"4225fef0cdba0c06c80000aa","content":"# Starch Test\n## Iodine Test\nAdd a few drops of iodine solution"},{"_id":"42268f331aba1d5f84000050","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42268d8d1aba1d5f8400004f","content":"# Results\nBlue-black: √\nYellow: X"},{"_id":"422692fc1aba1d5f84000051","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"4225fef0cdba0c06c80000aa","content":"# Reducing Sugars Test\n## Benedict's Test"},{"_id":"4226a8261aba1d5f84000053","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"422692fc1aba1d5f84000051","content":"# Sucrose\n1. Add 4 drops of hydrochloric acid\n2. Boil for 2-3 minutes\n3. Let it cool\n4. Add sodium hydrogen carbonate to neutralise the acid\n\nGo to solid/liquid"},{"_id":"4226ad961aba1d5f84000054","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"422692fc1aba1d5f84000051","content":"# Solid\n1. Cut up into smaller pieces\n2. Add 2cm3 of water\n3. Stir\n4. Decant the water\n\nGo to liquid step 2"},{"_id":"4226c5691aba1d5f84000055","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"422692fc1aba1d5f84000051","content":"# Liquid\n1. Add 2cm3 of the food sample\n2. Add 2cm3 of Benedict's solution\n3. Boil for 2-3 minutes"},{"_id":"4226ccfc1aba1d5f84000056","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4226c5691aba1d5f84000055","content":"# Results\nBlue: X\nBrick-red precipitate: √"},{"_id":"4225ff4fcdba0c06c80000ab","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42257e502b4899ee270000ca","content":"# Proteins"},{"_id":"4226ce231aba1d5f84000057","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225ff4fcdba0c06c80000ab","content":"# Info"},{"_id":"4226cf001aba1d5f84000058","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4226ce231aba1d5f84000057","content":"# Elements\nC, H, O, N (Sometimes S)"},{"_id":"4226d0de1aba1d5f84000059","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225ff4fcdba0c06c80000ab","content":"# Types\n* Amino acids\n* Polypeptides\n* Protein"},{"_id":"4226d2751aba1d5f8400005b","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"4225ff4fcdba0c06c80000ab","content":"# Roles\n* Synthesis of new protoplasm for growth & repair\n* Synthesis of enzymes & some hormones\n* Formation of antibodies to combat diseases"},{"_id":"4226d8991aba1d5f8400005c","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"4225ff4fcdba0c06c80000ab","content":"# Protein Test\n## Biuret Test"},{"_id":"4226d9e21aba1d5f8400005d","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4226d8991aba1d5f8400005c","content":"# Solid\n1. Cut up into smaller pieces\n2. Add 2cm3 of water\n3. Stir\n4. Decant the water\n\nGo to liquid step 2"},{"_id":"4226daf41aba1d5f8400005e","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4226d8991aba1d5f8400005c","content":"# Liquid\n1. Add 2cm3 food sample\n2. Add 2cm3 of Biuret solution"},{"_id":"4226dc241aba1d5f8400005f","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4226daf41aba1d5f8400005e","content":"#Results\nBlue: X\nPurple: √"},{"_id":"4225ff8acdba0c06c80000ac","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"42257e502b4899ee270000ca","content":"# Lipids"},{"_id":"4226dd811aba1d5f84000060","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225ff8acdba0c06c80000ac","content":"# Info"},{"_id":"4226e8021aba1d5f84000062","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4226dd811aba1d5f84000060","content":"# Elements\nC, H, O\nH > O"},{"_id":"4226e8b11aba1d5f84000063","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4226dd811aba1d5f84000060","content":"# Components\n* Fatty acids\n* Glycerol"},{"_id":"4226e9c61aba1d5f84000064","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225ff8acdba0c06c80000ac","content":"# Roles\n* Source of energy\n* Insulation\n* Transport agent for some vitamins and vital substances\n* Component of cell surface membrane\n* Prevents water loss"},{"_id":"4227133e1aba1d5f84000065","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"4225ff8acdba0c06c80000ac","content":"# Fats Test\n## Ethanol-emulsion Test"},{"_id":"42272f0e1aba1d5f84000066","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4227133e1aba1d5f84000065","content":"# Solid\n1. Cut up the food into smaller pieces\n2. Add 2cm3 of ethanol\n3. Shake thoroughly\n4. Decant to 2cm3 of water"},{"_id":"422735f31aba1d5f84000067","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4227133e1aba1d5f84000065","content":"# Liquid\n1. Add 2cm3 of food sample\n2. Add 2cm3 of ethanol\n3. Shake thoroughly\n4. Add 2cm3 of water"},{"_id":"422737b61aba1d5f84000068","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"4227133e1aba1d5f84000065","content":"Results\nCloudy white emulsion: √\nClear: X"},{"_id":"42257e8d2b4899ee270000cb","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"536a211b4de898da0684d477","content":"# Enzymes"},{"_id":"42257ebe2b4899ee270000cc","treeId":"536a211b4de898da0684d46e","seq":1,"position":5,"parentId":"536a211b4de898da0684d477","content":"# Human Nutrition"},{"_id":"4227509b1aba1d5f84000069","treeId":"536a211b4de898da0684d46e","seq":1,"position":0.5,"parentId":"42257ebe2b4899ee270000cc","content":"# Organs"},{"_id":"422751511aba1d5f8400006a","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4227509b1aba1d5f84000069","content":"# Mouth"},{"_id":"422751901aba1d5f8400006b","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"422751511aba1d5f8400006a","content":"# Salivary glands\nProduce and secrete saliva the mouth"},{"_id":"422758281aba1d5f8400006c","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"422751901aba1d5f8400006b","content":"# Mucus and water\n* Moistens mouth & tongue and softens food\n* Facilitates swallowing"},{"_id":"42275c6f1aba1d5f8400006d","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"422751901aba1d5f8400006b","content":"# Salivary amylase\n- Breaks down starch into maltose\n- pH 7\n - Optimal for salivary amylase activity\n- Lysozyme\n - Destroys bacteria"},{"_id":"42275d4d1aba1d5f8400006e","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"422751511aba1d5f8400006a","content":"# Buccal cavity\nSpace enclosed by the mouth"},{"_id":"422766781aba1d5f8400006f","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"422751511aba1d5f8400006a","content":"# Teeth\n Chewing action breaks up food into small pieces (mastication) to increase surface area to volume ratio for digestive enzyme action"},{"_id":"42276a631aba1d5f84000070","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"422751511aba1d5f8400006a","content":"# Tongue\n Rolls food and saliva into small masses (boli) to facilitate swallowing"},{"_id":"42276ac31aba1d5f84000071","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4227509b1aba1d5f84000069","content":"# Oesophagus\n Narrow, muscular tube that joins the pharynx and the stomach uses peristalsis to push food forward"},{"_id":"42276b761aba1d5f84000072","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"4227509b1aba1d5f84000069","content":"# Stomach"},{"_id":"42276f261aba1d5f84000077","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42276b761aba1d5f84000072","content":"# Distensible, muscular bag\n Stretches when temporarily storing food, informs the brain when fully-distended"},{"_id":"42276f6c1aba1d5f84000078","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42276b761aba1d5f84000072","content":"#  Thick, well-developed muscular wall\nPeristalsis churns the food to mechanically break them up and mix them forming chyme"},{"_id":"42276fa41aba1d5f84000079","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42276b761aba1d5f84000072","content":"#  Wall has numerous pits\nGastric glands which produce gastric juice which contains hydrochloric acid, pepsin and renin"},{"_id":"422770aa1aba1d5f8400007a","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42276fa41aba1d5f84000079","content":"# Hydrochloric Acid\n* Stops salivary amylase activity\n* Activates pepsinogen and prorennin\n* Provides acidic pH optimal for pepsin and rennin activities\n* Denatures proteins in food to exposes peptide bonds for hydrolysis by pepsin\n* Kills germs"},{"_id":"422771441aba1d5f8400007b","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42276fa41aba1d5f84000079","content":"# Pepsin\nPepsinogen (Inactive) + HCl > Pepsin (Active) \nProtein + Pepsin > Peptides"},{"_id":"422772ec1aba1d5f8400007c","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42276fa41aba1d5f84000079","content":"#Rennin\nProrennin (Inactive) + HCl > Rennin (Active)\nMilk protein caseinogen (Soluble) + Rennin > Casein (Insoluble)\nSo it stays longer in the stomach"},{"_id":"422778b73726cac2f700007b","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"42276fa41aba1d5f84000079","content":"# Lined by mucus layer\nProtection against damage by hydrochloric acid in gastric juice"},{"_id":"422774c11aba1d5f8400007e","treeId":"536a211b4de898da0684d46e","seq":1,"position":5,"parentId":"42276fa41aba1d5f84000079","content":"# Sphincters\nThe lower oesophageal sphincter connects stomach to the oesophagus and the pyloric sphincter connects stomach to the small intestine, they control the movement of food into and out of the stomach"},{"_id":"42276c331aba1d5f84000073","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"4227509b1aba1d5f84000069","content":"# Small Intestine"},{"_id":"42277a4a3726cac2f700007c","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42276c331aba1d5f84000073","content":"# Parts\n* Duodenum (U-shaped)\n* Jejunum\n* Ileum (Much-coiled)"},{"_id":"42277bdf3726cac2f700007d","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42276c331aba1d5f84000073","content":"# Intestinal Juice\n* Maltase\n* Sucrase\n* Lactase\n* Erepsin (Peptidase)\n* Lipase"},{"_id":"42276c7c1aba1d5f84000074","treeId":"536a211b4de898da0684d46e","seq":1,"position":5,"parentId":"4227509b1aba1d5f84000069","content":"# Gall Bladder\nStores bile produced by the liver which emulsifies fats increasing the surface area to volume ratio"},{"_id":"42276cae1aba1d5f84000075","treeId":"536a211b4de898da0684d46e","seq":1,"position":6,"parentId":"4227509b1aba1d5f84000069","content":"# Pancreas"},{"_id":"422784373726cac2f700007e","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42276cae1aba1d5f84000075","content":"# Pancreatic Juice\n* Insulin\n* Glucagon\n* Amylase\n* Trypsin/Chymotrypsin\n* Lipase\n* Nuclease"},{"_id":"42276eb41aba1d5f84000076","treeId":"536a211b4de898da0684d46e","seq":1,"position":7,"parentId":"4227509b1aba1d5f84000069","content":"# Large Intestine"},{"_id":"422788903726cac2f700007f","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42276eb41aba1d5f84000076","content":"# Colon\n*  Absorbs H2O, mineral salts and vitamins from undigested food\n* Peristalsis of colon wall propels undigested food to the rectum"},{"_id":"42278a453726cac2f7000080","treeId":"536a211b4de898da0684d46e","seq":1,"position":0.75,"parentId":"42257ebe2b4899ee270000cc","content":"# Liver"},{"_id":"42278ab93726cac2f7000081","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42278a453726cac2f7000080","content":"# Liver Vessels"},{"_id":"42278ea13726cac2f7000084","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42278ab93726cac2f7000081","content":"# Hepatic Portal Vein\nNutrient-rich blood from small intestine to liver"},{"_id":"42278f063726cac2f7000085","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42278ab93726cac2f7000081","content":"#  Hepatic Artery\nOxygenated blood from heart to liver"},{"_id":"42278f333726cac2f7000086","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42278ab93726cac2f7000081","content":"# Hepatic vein\nDeoxygenated blood from the liver to the heart"},{"_id":"42278d8f3726cac2f7000082","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42278a453726cac2f7000080","content":"# Functions\n* Deamination\n* Detoxification\n* Regulation of Blood Glucose Concentration\n* Protein synthesis\n* Bile production\n* Iron storage"},{"_id":"42278e143726cac2f7000083","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42278a453726cac2f7000080","content":"# Effects of Alcohol\n* Depressant\n* Reduced self-control\n* Slower reaction time\n* Excessive stomach acid secreted\n* Replaces liver cells with fibrous tissue by cirrhosis\n* Social Implications"},{"_id":"4225bca7cdba0c06c8000097","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42257ebe2b4899ee270000cc","content":"# Zoom in"},{"_id":"4225bd30cdba0c06c8000098","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225bca7cdba0c06c8000097","content":"# Peristalsis\nThe rhythmic wave-like antagonistic contraction and relaxation of smooth muscle layers, outer longitudinal muscles and inner circular muscles, causing dilation and constriction to mix and propel food"},{"_id":"4225ca49cdba0c06c8000099","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225bca7cdba0c06c8000097","content":"# Villi\nIncrease surface area to volume ratio"},{"_id":"4225cbd5cdba0c06c800009a","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225ca49cdba0c06c8000099","content":"#  1-cell thick epithelium\nSmaller diffusion distance, has microvilli to increase surface area to volume ratio"},{"_id":"4225cc1ecdba0c06c800009b","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225ca49cdba0c06c8000099","content":"#  Blood and Lymph Capillaries\nMaintain concentration gradients"},{"_id":"4225cc64cdba0c06c800009c","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4225cc1ecdba0c06c800009b","content":"# Blood Capillaries\nTransports glucose and amino acids"},{"_id":"4225ccbccdba0c06c800009d","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4225cc1ecdba0c06c800009b","content":"# Lymph Capillaries (Lacteals)\nTransports lipids"},{"_id":"42257f092b4899ee270000cd","treeId":"536a211b4de898da0684d46e","seq":1,"position":6,"parentId":"536a211b4de898da0684d477","content":"# Plant Nutrition"},{"_id":"42279ea03726cac2f7000091","treeId":"536a211b4de898da0684d46e","seq":1,"position":0.5,"parentId":"42257f092b4899ee270000cd","content":"# Leaf Structure"},{"_id":"42279fe43726cac2f7000092","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42279ea03726cac2f7000091","content":"# External"},{"_id":"4227a01a3726cac2f7000093","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42279fe43726cac2f7000092","content":"# Network of Veins\nVeins carry water and mineral salts to the cells in the lamina and carry manufactured food from these cells to other parts of the plant"},{"_id":"4227a06a3726cac2f7000094","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42279fe43726cac2f7000092","content":"# Lamina\nThe lamina has a large flat surface compared to its volume. This enables it to obtain the maximum amount of sunlight for photosynthesis\nA large, thin lamina also means that carbon dioxide can rapidly reach the inner cells of the leaf"},{"_id":"4227a0c83726cac2f7000095","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42279fe43726cac2f7000092","content":"# Leaf Arrangement\n* Leaves are always organised around the stem in a regular pattern\n* Ensures that the leaves are not blocking one another from the sunlight and that each leaf receives sufficient sunlight"},{"_id":"4227a1963726cac2f7000096","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"42279fe43726cac2f7000092","content":"# Petiole\nThe petiole holds the lamina away from the stem so that the lamina can obtain sufficient sunlight and air in come leaves"},{"_id":"4227a2243726cac2f7000097","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42279ea03726cac2f7000091","content":"# Internal"},{"_id":"4227a2663726cac2f7000098","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4227a2243726cac2f7000097","content":"# Upper Epidermal Cells\n* Single layer of closely packed cells\n* Covered on the outside by waxy and transparent cuticle. \n* Epidermis protects the inner regions of the leaf"},{"_id":"4227a2df3726cac2f7000099","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4227a2243726cac2f7000097","content":"# Palisade Mesophyll Cells\n* One or two layers of closely packed, long and cylindrical cells with their long axes at right angles to the epidermis\n* Contain numerous chloroplasts"},{"_id":"4227a3393726cac2f700009a","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"4227a2243726cac2f7000097","content":"# Spongy Mesophyll Cells\n* Irregularly shaped cells that are loosely packed with numerous large intercellular air spaces\n* Fewer chloroplasts than palisade mesophyll cells\n* Cells covered with thin moisture film\n* Contain vascular bundle, xylem and phloem"},{"_id":"4227a3c63726cac2f700009b","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"4227a2243726cac2f7000097","content":"# Lower Epidermal Cells\n* Single layer of closely packed cells beneath mesophyll\n* Covered by an outer layer of cuticle to reduce water loss"},{"_id":"4227a4333726cac2f700009c","treeId":"536a211b4de898da0684d46e","seq":1,"position":5,"parentId":"4227a2243726cac2f7000097","content":"# Guard Cells"},{"_id":"4227a46d3726cac2f700009d","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"4227a4333726cac2f700009c","content":"# Day\n* Increase water potential\n* Produce glucose\n* Convert light to chemical energy to be used to pump K+ ions into guard cells from neighbouring epidermal cells by active transport\n* Water from other cells enter the guard cells by osmosis\n* Swell and become turgid\n* Since they have a thicker cellulose wall on one side of the cell, the swollen guard cells move further apart and pull the stoma open"},{"_id":"4227a5263726cac2f700009e","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"4227a4333726cac2f700009c","content":"# Night\n* Lower water potential\n* Sugar is used up\n* K+ ions diffuse out\n* Water leaves the guard cells by osmosis\n* Become flaccid and the stoma closes."},{"_id":"4227a5d43726cac2f700009f","treeId":"536a211b4de898da0684d46e","seq":1,"position":6,"parentId":"4227a2243726cac2f7000097","content":"# Stomata\nMinute openings usually found on the lower epidermis"},{"_id":"4227a6b63726cac2f70000a0","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42279ea03726cac2f7000091","content":"# Adaptations\n* Petiole\n* Thin lamina\n* Large flat surface\n* Waxy cuticle on upper and lower epidermal layers\n* Stomata present mostly in lower epidermis\n* Chloroplasts containing chlorophyll\n* More chloroplasts in upper palisade tissue\n* Inter-connecting system of air spaces in mesophyll \n* Veins containing xylem and phloem"},{"_id":"422798b43726cac2f7000088","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42257f092b4899ee270000cd","content":"# Photosynthesis"},{"_id":"422799d93726cac2f7000089","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"422798b43726cac2f7000088","content":"# Requirements\n* Carbon Dioxide\n* Water"},{"_id":"42279aea3726cac2f700008a","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"422798b43726cac2f7000088","content":"# Products\n* Glucose\n* Oxygen\n* Water (Optional)"},{"_id":"42279b653726cac2f700008b","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"422798b43726cac2f7000088","content":"# Chemical Equations"},{"_id":"42279bb33726cac2f700008c","treeId":"536a211b4de898da0684d46e","seq":1,"position":1,"parentId":"42279b653726cac2f700008b","content":"# Light-Dependent\nLight energy -> Chemical energy\n12H2O (Photolysis) -> 6O2 + 24H"},{"_id":"42279cda3726cac2f700008d","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42279b653726cac2f700008b","content":"# Light-Independent\n6CO2 + 24H (Chemical energy) -> C6H12O6 + 6H2O\n(Enzyme-controlled reactions)"},{"_id":"42279d183726cac2f700008e","treeId":"536a211b4de898da0684d46e","seq":1,"position":3,"parentId":"42279b653726cac2f700008b","content":"# Overall\n6CO2 + 12H2O > C6H12O6 + 6O2 + 6H2O"},{"_id":"42279d713726cac2f700008f","treeId":"536a211b4de898da0684d46e","seq":1,"position":4,"parentId":"42279b653726cac2f700008b","content":"# Simplified\n6CO2 + 6H2O > C6H12O6 + 6O2\nCarbon dioxide + Water > Glucose + Oxygen"},{"_id":"42279dc63726cac2f7000090","treeId":"536a211b4de898da0684d46e","seq":1,"position":2,"parentId":"42257f092b4899ee270000cd","content":"#Limiting Factors\n* Light intensity\n* Carbon dioxide concentration\n* Temperature"}],"tree":{"_id":"536a211b4de898da0684d46e","name":"Biology","publicUrl":"biology"}}