Predicted questions Flashcards
What are enzymes
Large proteins that catalyse reactions
Explain lock and key theory (4 points)
- Enzyme has complementary active site to the substrate
- The substrate will bind to the active site
- Where it will be broken dish until smaller molecules easier to digest
- Product is released and enzyme’s active site will remain the same and break down more substrates
What happens to rate of reaction of enzymes as temp increases
Rate of reaction increases
Enzyme and substrate molecule move quicker and collide more frequently
What happens at optimum temp for an enzyme
The reaction works as fast as possible and is most effective here
What happens to enzyme when temp is too high and past optimum
Denature and stop working
What happens when an enzyme denatures
Shape of active site will change so substrate can no longer fit into active site so enzyme can not catalyse reaction
Give three digestive enzymes
Amylase
Protease
Lipase
Where are the sites of production for amylase enzyme (3)
Salivary glands
Pancreas
Small intestine
Where are the 3 sites of production for protease enzymes
Stomach
Pancreas
Small intestine
Where are the 2 sites of production for lipase
Pancreas and small intestine
What reaction is catalysed with amylase
Starch to glucose
What reaction is catalysed by protease
Proteins to amino acids
What reaction is catalysed by lipase
Lipids to fatty acid and glycerol
What are the two things that can denature and enzyme
Extreme of PH or very high temp
Describe the pathway of air
Mouth and nose
Trachea
Bronchi
Bronchioles
Alveoli
How are the alveoli adapted for gaseous exchange
Good blood supply
Large SA
Capillaries and alveoli are one cell thick so diffusion distance is shorter
Moist walls
Explain steps of gaseous exchange
- We inhale and alveoli fill with oxygen
- Blood in capillaries surrounded is deoxygenated so containing lots of carbon dioxide
- Oxygen diffuses down the concentration gradient into capillary bloodstream which has low concentration of oxygen
- Carbon dioxide diffuse downs it’s concentration gradient into alveoli
What does TMV stand for and what organism does it affect
Tobacco mosaic virus
Plants
How is TMV spread
Direct contact with infected plants
Animal and plant vectors
Soil: pathogen remains in soil
What are the TMV symptoms
Mosaic pattern of discolouration (yellow) on leaves where chlorophyll is destroyed
Stunted growth due to reduced ability to photosynthesise
How is TMV prevented
Pest control
Growing TMV resistant strains
What can alcohol lead to
Liver disease
Impaired brain function
Affected development of unborn babies
What are the effects of the risk factors for alcohol
Liver cirrhosis - liver cannot remove toxins and produce enough bile for digestion
Damages brain and causes anxiety and depression
Alcohol can pass through placenta risking miscarriage, premature birth, birth defects
What is cancer the result of
Changes in cells that lead to uncontrolled growth and division by mitosis
