SMDDDDD Flashcards
what does the xylem do
it transports water and mineral ions from the root upwards to the leaves
what do lignin walls do
strengthens xylem
what do phloem transport
sugars from the leaves to area of storage
what do palisade cells contain
lots of chloroplasts which absorb light in photosynthesis and make sugar/glucose. palisade cells are densely packed to maximise absorption of light
How to calc Magnification
image over actual and to convert nm to mm times 1000
Define diffusion
Net movement of particles from an area of high concentration to low concentration
How do substances enter cells
By diffusion through cell membrane
How can diffusion speed be increased in some organism
- Reduced diffusion distances, shorter distance equals to faster diffusion
- Concentration gradient kept high, equilibrium is not reached so diffusion continues
- Large surface area for diffusion to tak3 place across the cell membranes
Osmosis
Net movement of water molecules from an area of high water potential to an area of low water potential across a partially permeable membrane
How does water enter cells
Osmosis
How does osmosis affect plant and animals differently
Plant cells not permanently damaged , cell walls give plants cell support
Animal cells permanently damaged and cells shrink with water loss and wil burst if swelled too much
Define active transport
Net movement of particles from area of low concentration to high concentration as it requires energyyyy
What are the two groups of carbs called
Monosaccharides and polysaccharides
What are proteins
Chains of amino acids who order has been determined by genes
What is the structure of a lipid
3 fatty acids and 1 glycerol molecule
What is theFood test for starch
Iodine,
Positive result means it turns blueish black
Name the complementary bases
Adenine and thymine, Guanine and cytosine (ATGC)
What is the rate of enzyme activity at low temp
Enzymes and substrates hv little kinetic energy so they don’t collide quickly, hence the rate of reaction is low
What happens to enzymes at very high temp
It becomes denatured as the active site changes shape meaning that the substrate can no longer fit
Give me the photosynthesis equation
Carbon dioxide + water => glucose + oxygen
Function of chlorophyll
Transfers light energy to chemical energy
Energy produced used for synthesis of carbohydrates
Limiting factors for photosynthesis
Temperature, carbon dioxide, light intensity
In leafs, how is the waxy cuticle adapted for its function
It prevents transpiration ( loss of water vapour)
how is the upper epidermis adapted to its function
Transparent to allow light to enter leaf
How is the palisade mesophyll adapted for its function
Contains lots of chloroplasts which absorb light in photosynthesis