Enzymes
Circulatory System
Digestive System
Homeostasis
Endocrine System
100
Why is an enzyme described as a biological catalyst?
Catalyst speeds up reactions.
Biological- made up of living things.
100
What is the name of the part labelled 6?
Aorta
100
What type of consumer is the animal below? Justify your answer.
Carnivore. Sharp canines used to tear meat.
100
The student in the picture has a red face and is sweating after being in very hot weather.
Explain how vasodilation helps the body maintain a constant temperature in this situation.
During vasodilation, blood vessels near the skin widen, allowing more blood to flow close to the surface of the skin. More heat is lost to the surroundings, helping to cool the body down.
100
What is the name of the gland labelled 6? What hormone does it release?
Adrenal gland releases adrenaline.
200
What is the name of the substance that an enzyme acts on?
substrate
200
What are two differences between arteries and veins?
200
What is the name of the structure below and in what part of the digestive system is it found?
Villus. Found in small intestines.
200
After eating a large slice of cake, this hormone is released to lower blood glucose levels.
Insulin
200
A student feels tired all the time, gains weight easily, and has a slow heart rate. These symptoms may be caused by low levels of this hormone.
Thyroxine
300
What are the names of the parts labelled A and D?
A- Substrate
D- Product
300
What is meant by the phrase double circulation?
Blood pumps through the heart twice in one complete circuit.
300
What is the name and function of the part labelled C?
Lacteal. Absorbs fat.
300
This hormone helps the kidneys reabsorb more water when the body is dehydrated.
ADH (Anti-diuretic Hormone).
300
This gland is known as the “master gland” because it controls other endocrine glands.
Pituitary gland
400
A student added a biological detergent containing protease enzymes to a stained shirt and washed it in water at 95°C. After washing, many of the protein stains were still on the shirt.
Explain why the protease enzymes did not remove the stains effectively.
The water temperature was too high, causing the protease enzymes in the detergent to become denatured. Their active sites changed shape, so they could no longer break down the protein stains.
400
What is the name of the pigment in red blood cells that binds with oxygen for transport around the body?
Haemoglobin
400
Describe two ways that the small intestine is adapted to carry out its function of absorption.
Long. Thin lining. Heavily folded. Microvilli increases surface area. Good supply of blood. Lacteals that absorb fat.
400
Define homeostasis.
Maintaining a constant internal environment.
400
What are two commercial uses of horomones?
Steroids - e.g. enhance athletic performance.
FSH and LH- for infertility
Growth hormone - speed up animal growth
Insulin - for diabetics
500
Use the graph below to explain the activity of enzymes.
Pepsin has its highest activity at about pH 2, which is its optimum pH. As the pH moves further away from pH 2, the enzyme activity decreases because the shape of the active site changes, reducing the ability of the substrate to fit properly.
500
Why is the left side of the heart thicker than the right side?
Because it has to pump blood throughout the whole body.
500
Define peristalsis.
The wave-like movement that pushes food down the alimentary canal.
500
List three ways that the body reacts to counteract extremely cold temperatures.
Vasoconstriction, piloerection (hair raising), stopping sweat production.
500
The image below shows a disease called goiter. What is the cause of the disease?
Iodine deficiency