B2 - Organisation Flashcards
What is meant by an organ system
a group of organs that complete a task e.g respiration
What is a tissue?
A group of cells that work together to carry out a function.
What is an organ?
A group of tissues that work together to perform a function
What is the purpose of an active site
The active site is where the substrate fits into the enzyme.
When do enzymes denature
1) When the PH is to high or low
2) When the temperature is too high
Which group of digestive enzymes does amylase belong too?
carbohydrates
What is the product reaction of amylase?
sugars
What are the functions of bile and why is it important?
It neutralises the acid from the stomach in the small intestine and makes the conditions alkaline, the enzymes in the intestine work best in this condition. It emulsifies fat, which increases the surface area and makes digestion happen faster.
When you breath in, air flows through a series of tubes, including the trachea and the ………………. . The ………………. are where gas exchange takes place. Gas exchange ………………. the blood allows the removal of ………………. from the body.
1) bronchi
2) alveoli
3) oxygenates
4) carbon dioxide
Describe the role capillaries play in gas exchange in the lungs.
The capillary carries blood hat is returning from the rest of the body and contains a higher concentration of carbon dioxide than in the lungs. The carbon dioxide diffuses into the alveoli, where there is a lower concentration, to be breathed out. The capillary also picks up oxygen from the alveoli, which contains a higher concentration of oxygen than in the blood. Oxygen diffuses from the alveoli into the blood , where there is a lower concentration, to be carried to the blood cells.
Explain why the human circulatory system is described as a ‘double circulatory system’
Because it consists of two circuits joined together. The first one pumps oxygenated blood to the lungs to take in oxygen and returns oxygenated blood to the heart. The second one pumps oxygenated blood around all the other organs of the body and returns deoxygenated blood to the heart.
Describe how the heart beat is controlled.
The heart beat is controlled by a group of cells in the right atrium wall that act as a pacemaker.
What blood vessel has valves and why?
Veins, to prevent back flow of blood.
Describe the function of platelets
They help the blood to clot at wounds
How are white blood cells adapted to their specific function.
Some white blood cells can change shape to engulf microorganisms in a process called phagocytosis. Others produce antibodies to fight microorganisms or antitoxins to neutralise any toxins produced by microorganisms.
