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Biology M2 - Coggle Diagram

- - - - function: transport of water and minerals driven by the "pull" of transpiration
        
        keep the cells turgid to support the structure of plant
        
        water used in photosynthesis
      - structure:
        
        paths:
        
        xylem vessels in general: roots->stem->leaves
        
        water: root hair cell->root cortex cells->xylem->leaf mesophyll cells
        
        cells:
        
        formed of hollow, dead cells
        
        deposits of lignin in cell walls
        
        strengthened its thick outer walls:
        
        to withstand the pressure of water movement
        
        causes cells to die and become empty
        
        cells joined end to end without end walls
        
        form continuous tube that allowed free passage of water and mineral ions
        
        direction: one way flow
    - - function:
        
        translocation:
        
        the transport of sugar and amino acids in phloem tubes:
        
        from source to sink
        
        e.g. transport from storage organs to other parts of plant
        
        when plants loses leaves in winter for continuous respiration
        
        when plant are growing in the spring
        
        source: where food is produced by photosynthesis or stored
        
        sink: regions of storage or use
        
        e.g. transport from leaves to storage organs like roots
        
        when leaves are photosynthesizing rapidly in summer
      - structure:
        
        path: leaves->stem->roots
        
        direction: two way flow
        
        cells:
        
        thick outer walls made of cellulose
        
        made of living cells
        
        cells joined end to end with sieve plates:
        
        easy flow of substance of one cell to the next
        
        sieve plates are cell walls with holes
    - - cross-section of leaf.
      - both vessels arein groups called vascular bundles
      - cross-section of root.
      - cross-section of stem.
  - - - single-celled extensions
      - type: epidermis cells
    - - absorb water and minerals from the soil
      - water enters the cells by osmosis: water has a higher water potential than the cytoplasm of cell
    - - root hair increases surface area of cells:
        
        higher rate of osmosis and active transport for absorption of water and mineral (correspondingly)
  - - - evaporation at the surfaces of mesophyll cells followed by:
        
        diffusion through the stomata when there's concentration gradient
    - - cools the leaves as evaporation requires heat energy
      - removes excess water from the plant
      - however, if the plant transpires more water than it absorbs from the soil, wilting occurs as cell walls cannot support the plant without water in cells
  - - - temperature:
        
        condition: adjust room temp.
        
        result:
        
        temperature increase, rate increase
        
        more KE energy quickens evaporation and diffusion
      - wind speed:
        
        condition: use electric fan
        
        result:
        
        wind speed increase, rate increase
        
        airflow removes water vapor from the air surrounding the leaf, increasing the concentration gradient between leaf and air
      - humidity:
        
        condition: adjust room humidity
        
        results:
        
        humidity increase, rate decrease
        
        air saturated with water vapor, concentration gradient decreases
- - - - arteries
        
        direction: away the heart
        
        narrow lumen (tube space) to maintain high blood pressure
        
        all arteries carry oxygenated blood except pulmonary artery
        
        thick and muscular cells with elastic fibers (to withstand high blood pressure)
        
        do not have valves except in the heart
        
        arteries narrow to arterioles and then capillaries
      - veins
        
        direction: towards the heart
        
        all veins carry deoxygenated blood except pulmonary vein
        
        wide lumen (tube space), so blood pressure is low
        
        thin walls
        
        have valves to prevent blood from flowing backwards because blood is under low pressure
        
        capillaries widen to venules and then veins
      - def. system of tubes which carries blood to parts of body
      - Capillaries
        
        carry blood to cells of body tissues
        
        transport oxygenated blood from arteries to cells
        
        transport deoxygenated blood from cells to veins
        
        tiny structure
        
        very narrow lumen
        
        one cell thick walls
        
        substances can easily diffuse in and out, facilitating substance exchange between blood and cells
        
        have gaps that leak blood plasma to form tissue fluid to provide oxygen and nutrients to cells
    - - coronary heart disease
        
        coronary arteries
        
        heart is made of muscle tissues, its blood supplied from coronary arteries
        
        cause:
        
        coronary arteries become blocked by fatty deposits formed from cholesterol
        
        the arteries are not as elastic
        
        cannot stretch to accommodate the blood going through them
        
        leading to restricted blood flow
        
        risk factors:
        
        unhealthy diet
        
        stress
        
        smoking
      - four-chambered
      - right side
        
        1-right atrium receives deoxygenated blood from vena cava
        
        3-right ventricle contracts and pumps blood to the pulmonary arteries through the semilunar valve
        
        2-right atrium push blood to right ventricle through atrioventricular valve
        
        4-blood travels to the lungs and moves through the capillaries past the alveoli where gas exchange takes place
      - left side
        
        5-left atrium receive oxygenated blood from pulmonary veins
        
        7-left ventricle contracts strongly and pumps blood to the aorta
        
        6-left atrium push blood to left ventricle through atrioventricular valve
        
        8-blood passes through body capillary and returns from vena cava. blood release O2 for cell's respiration, getting deoxygenated themselves
      - septum
        
        two sides of heart are separated by a muscle wall called
        
        prevent mixing O2 & deO2 blood
      - valves
        
        function: prevent blood from flowing backwards. Open only when muscles contract so blood squeezes past them out of heart, afterwards shut to avoid blood flowing back to heart
        
        types:
        
        atrioventricular valves
        
        separate atria from ventricles
        
        open only when atria contract
        
        semilunar valves
        
        found in top of aorta and pulmonary artery of the heart
        
        open when the ventricles contract
      - monitoring heart activity
        
        measure heart rate (or pulse rate) in beats per minute
        
        observation: heart rate increases during physical activity and gradually returns to resting heart rate after exercise
        
        sufficient blood is taken to the working muscles to provide them with enough nutrients and oxygen for increased respiration
        
        waste products can be removed at a faster rate
        
        if cells respired anaerobically, extra oxygen is used to break down lactic acid（乳酸） formed
      - ventricles have thicker walls than atriums as they are pumping out blood, so they need to generate a higher pressure
      - left ventricle has thicker muscle walls than right ventricle as it pumps blood at a higher pressure around the entire body whereas right ventricle pumps with lower pressure to the lungs
    - - for every circuit of body, the blood passes through the heart twice
      - advantage: blood going through the lungs loses a lot of pressure. By returning to the heart, the pressure can be raised and the cells can be supplied with oxygen and glucose more frequently
    - - cells 45%
        
        white blood cells
        
        structure
        
        big nucleus
        
        large cells
        
        function: defend the body against infection by pathogens; part of immune system
        
        types:
        
        phagocytes
        
        function: carry out phagocytosis: engulfing(1) and then digesting(2) pathogens using digestive enzymes
        
        can detect pathogenic cells
        
        multi-lobed nucleus
        
        lymphoctyes
        
        functions:
        
        produce antibodies to destroy pathogenic cells
        
        produce antitoxins to neutralise toxins released by pathogens
        
        large and round neucleus
        
        platelets
        
        fragments of cells
        
        function: help blood to clot by forming scabs
        
        prevent continued & significant blood loss
        
        scabs seals the wound in an insoluble patch that prevents the entry of microorganisms, which could cause infection
        
        SERIES: platelets release chemicals that causes:
        
        soluble fibrinogen proteins to convert into insoluble fibrin which forms:
        
        an insoluble mesh across the wound that:
        
        1 more item...
        
        red blood cells
        
        structure
        
        no nucleus
        
        plenty of protein haemoglobin
        
        biconcave discs->large surface area
        
        function: transport oxygen around the body (carry oxygen in the form of oxyhaemoglobin)
      - plasma 55%
        
        yellow liquid
        
        function: transport CO2, nutrients, minerals, hormones, and heat energy.
  - - - Aorta
        
        Capillary
        
        Capillary
        
        Vena Cava
        
        Right atrium
        
        Right ventricle
        
        1 more item...
        
        hepatic(from liver) vein, renal(from kidney) vein
        
        note: there are different capillaries, arteries, veins for different organs.
        
        hepatic (to liver) artery, hepatic portal(from gut to liver)vein, renal(to kidney) artery
    - - Heart
        
        Heart
        
        Heart
  - - - one atrium and one ventricle
    - - for every circuit of body, the blood passes through the heart once