Exchange Of Materials Flashcards
(31 cards)
What type of membrane is the cell membrane?
Partially permeable membranr
Osmosis is the movement of water
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What does partially permeable mean?
A type of biological membrane that will allow certain molecules or ions to pass through it by diffusion/osmosis
What is osmosis and what happens during it?
Osmosis is the diffusion of water across a partially permeable membrane. The water particles move from an area of high water concentration to an area of low concentration
Osmosis refers to the movement of water molecules only, & osmosis does not need energy in order for it to take place
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If a substance is in short supply, what process do cells use to absorb the substance?
Active transport takes place
What is active transport and what happens during it?
Active transport is the movement of molecules from an area of low concentration to an area of high concentration. Against the concentration gradient
Active transport uses energy from respiration
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Why does active transport require energy?
Because the particles are being absorbed against a concentration gradient
Why is glucose used during exercise?
To release energy
What is the name given to the solution thats drink concentration matches the body fluids?
An isotope
What do sports drinks contain?
Water- to replace water lost when sweating
Sugar- to replace sugar used for energy release
Mineral ions- to replace those lost in sweating
How are mineral ions lost from the body during exercise?
By sweating
The lungs contain the gaseous exchange surface. What helps increase the surface area of the lungs?
Alveoli (air sacs)
Alveoli have thin walls, a large surface area and good blood supply
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Which muscles contract when you breathe?
The intercostal muscles
Ventilation occurs due to changes of pressure inside the chest
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3 reasons why someone may find it hard to breathe:
- If the alveoli are damaged, the surface area for gaseous exchange is reduced.
- If the tubes leading to the lungs are narrowed, less air can be moved through them
- If the person is paralysed, the muscles on the ribcage will not work
What are the two artificial breathing aids?
- The iron lung
2. Positive pressure aids
What does soluble mean?
Capable of being dissolved
Always relate the features of an exchange surface to its function
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2 features of villi which make them efficient exchange surfaces:
- The walls of the vili are very thing
2. There are many capillaries close to the wall
What are the steps to exchange in the gut?
The food we eat is digested in the gut into small, soluble molecules. In the small intestine these solutes are absorbed into the blood. The villi lines the inner wall of the small intestine, its large surface area increases absorption. Soluble products can be absorbed through the vili by either diffusion or active transport
What are the processes to exchange is plants?
Gases diffuse through holes called stomata. the size of the stomata is controlled by the guard cells.
