2.1 Flashcards
(26 cards)
Cells
Basic building blocks of all living organisms.
Tissue
Group of cells with a similar structure and function.
Organs
Aggregations of tissues performing specific functions.
Organ system
Groups of organs working together to perform specific functions
Organism
Group of organ systems which work together to form an organism.
Digestive system
Consist of organs that work together to digest and absorb food.
Effect of temperature on enzymes.
- All enzymes have an optimum temperature (~37ºC).
- As temperature increases, the enzyme becomes more active.
- When the temperature surpasses its optimum temperature, the enzyme denatures as its active site alters, so it can no longer catalyse the reaction.
Effect of pH on enzymes.
- All enzymes have an optimum pH.
- As the pH increases or decreases, the enzyme either becomes more or less active.
- Extreme pH values means the enzyme denatures as its active site alters, so it can no longer catalyse the reaction.
Equation for rate of chemical reactions.
Rate = change in mass ÷ time taken
Significance of the active site in enzyme function.
The shape of their active site is responsible for the specific reactions that they are able to catalyse.
‘Lock and key’ theory.
- The enzyme is the lock and the substrate is the key.
- The enzyme’s active site is complementary to the substrate.
- They bind to form an enzyme-substrate complex which breaks the substrate into products.
Site and action of carboghydrase (amylase) production.
- Salivary glands, pancreas and small intestine.
- Break down starch into simple sugars.
Site and action of protease production.
- Stomach, pancreas and small intestine.
- Break down proteins into amino acids.
Site and action of lipase production.
- Pancreas and small intestine.
- Break down lipids into glycerol and fatty acids.
Digestive enzymes function.
Break down large insoluble food molecules into small soluble food molecules that can be absorbed into the blood
Use of products of digestion.
- Build new carbohydrates, proteins and lipids.
- Some glucose is used in respiration.
Site and action of bile.
- Made in the liver, stored in the gallbladder.
- Increase rate of lipid breakdown by lipase: neutralises HCl acid from stomach due to alkalinity; emulsifies lipids into droplets to increase surface area.
Circulatory system
Consists of organs that work together to supply useful substances (e.g. oxygen) and removes waste products from tissues.
Human heart.
Organ that pumps blood around the body in a double circularity system.
Function of left and right ventricle
- Left: pumps oxygenated blood around the whole body.
- Right: pumps deoxygenated blood to the lungs for gas exchange.
Blood vessels functions associated with the heart
- Vena cava: pumps deoxygenated blood into right atrium, through the right ventricle.
- Pulmonary artery: carries deoxygenated blood from right ventricle to lungs.
- Pulmonary vein: carries oxygenated blood from lungs through left atrium, to the left ventricle.
- Aorta: carries oxygenated blood from the left ventricle to the rest of the body.
Reason for thicker side of heart
Left side is thicker to withstand higher pressures needed to pump blood around the body.
Valve function
Prevent back flow.
Importance of double circulatory system.
Makes circulatory system more efficient - no mixing of oxygenated and deoxygenated blood so can provide sufficient oxygen to tissues.
