Exchange of materials

Question 1

Osmosis: What is Osmosis?

Answer 1

Osmosis is the movement of water through a partially permeable membrane (just for Lucy)

Question 2

Osmosis: How is it similar to diffusion?

Answer 2

It moves water molecules randomly and does not need energy from the cell

Question 3

Osmosis: What is another way of saying High water concentration?

Answer 3

a dilute solution

Question 4

Osmosis: What is another way of saying low water concentration?

Answer 4

a more concentrated solution

Question 5

Osmosis: Is the cell membrane permeable?

Answer 5

the cell membrane is partially permeable

Question 6

Active Transport: What do cells use active transport for?

Answer 6

Active transport is used to absorb substances across partially permeable membranes against the concentration gradient

Question 7

Active Transport: What is needed for active transport?

Answer 7

Energy from repiration

Question 8

Active Transport: What do cells absorb from dilute solutions?

Answer 8

ions

Question 9

Active Transports: What can be reabsorbed in the kidney tubules by active transport?

Answer 9

Glucose

Question 10

The sports drink dilemma: What happens when you exercise?

Answer 10

You muscles respire energy. Glucose is used in respiration

Question 11

The sports drink dilemma: When you get hot you sweat what is in sweat ? What happens if you sweat too much?

Answer 11

Sweat contains water and mineral ions. If you sweat too much you can become dehydrated

Question 12

The sports drink dilemma: What should you do after exercise? Why?

Answer 12

You should drink water or energy drinks to replace sugars, mineral ions and water to replace what you have lost during exercise.

Question 13

The sports drink dilemma: What is in sports drinks?

Answer 13

Sports drinks are solutions of sugar and mineral ions

Question 14

The sports drink dilemma: What does the water in sports drink do?

Answer 14

It helps to rehydrate your body cells

Question 15

Exchanging materials: What are efficient exchange surfaces like?

Answer 15

Have large surface areas, thin walls, or a short diffusion path, also an effcient transport system

Question 16

Exchanging materials: What increases the surface are of the lungs?

Answer 16

The alveoli (air sacs)

Question 17

Exchanging materials: What has a special exchange surface?

Answer 17

Large, complex, organisms, to obtain all food and oxygen they need.

Question 18

Exchanging materials: Where does the oxygen diffuses into?

Answer 18

Diffuses back into the many capillaries surrounding the alveoli

Question 19

The sports drink dilemma: What are the benefits to sports drinks ?

Answer 19

Some sports scientists this it is just as good as drinking water for a short period of exercise. The drinks may be better to help athletes who need to replace mineral ions and sugers as well as water.

Question 20

Exchanging materials: What has a special exchange surface?

Answer 20

Large, complex, organisms, to obtain all food and oxygen they need.

Question 21

Ventilating the lungs: The lungs contain exchange surface of the breathing system, what is exchanged?

Answer 21

Oxygen is exchanged for carbon dioxide

Question 22

Ventilating the lungs: Where the lungs situated?

Answer 22

In the thorax, inside the rib cage above the diaphragm (which separates the lungs from the abdomen)

Question 23

Ventilating the lungs: What happens when we breath in?

Answer 23

-The intercostal muscles, between the ribs and the diaphragm contract -The ribcage moves up and out and the diaphragm flattens -The volume of the thorax increases -The pressure in the thorax decreases and the air is dawn in

Question 24

Ventilating the lungs: What happens when we breath out?

Answer 24

-The intercostal muscles of the ribcage and diaphragm relax -The ribcage moves down and in and the diaphragm becomes domed -The volume of the thorax decreases -The pressure increases and air is forced out

Question 25

Ventilating the lungs: What is the movement of the air in and out of the lungs called?

Answer 25

Ventilation.

Question 26

Artificial breathing aids: What are some of the reasons why someone cannot get oxygen into their bloodstream?

Answer 26

-If the alveoli are damaged, the surface area for gas exchanged is reduced -If the tubes leading to the lungs are narrowed, less air can be moved through them -If the person is paralysed, their muscles will not work to pull the ribcage up and out.

Question 27

Artificial breathing aids: Name three breathing aids and explain them

Answer 27

- The 'iron lung' was used for people with polio who were paralysed. The person lay with their chest sealed in a large metal cylinder. When air was drawn out of cylinder the person's chest moved out and they breathed in. The vaccum which was formed inside the cylinder created a negative pressure. When air was pumped back in to the cylinder it created pressure on the chest and forced air out of the person's lungs. -Breathing aids which force measured amounts of air into the lungs use positive pressure. Bags of air linked to masks can force air down the trachea. -Positive pressure aids are often smaller, easier to manage in the home can be linked to computers for control.

Question 28

What are used for active transport?

Answer 28

Transport Proteins

Question 29

How can active transport work?

Answer 29

The cells can absorb ions and release them

Question 30

Give an example of a process in the human body which uses active transport

Answer 30

Reabsorption of glucose in the kidney tubules

Question 31

Why are the lungs ventilated?

Answer 31

To maintain a steep diffusion gradient

Question 32

Which muscles control breathing and where are they?

Answer 32

Intercostal muscles between the ribcage and diaphragm

Question 33

Who was the iron lung used for?

Answer 33

People with polio who were paralysed

Question 34

What are the names of the upper and lower parts if the body? what separates them?

Answer 34

Thorax and abdomen separated by the diaphragm

Question 35

What do positive pressure aids force air down?

Answer 35

the trachea

Question 36

Benefits of positive pressure aids?

Answer 36

Small, easy to manage in the home, can be connected to a computer device for control.

Question 37

Exchange in the gut: The food we eat is digested in the gut into?

Answer 37

Small soluble molecules

Question 38

Exchange in the gut: Which part of the gut are small soluble molecules absorbed into the blood?

Answer 38

small intestine

Question 39

Exchange in the gut: What line the inner surface of the small intestine?

Answer 39

Villi

Question 40

Exchange in the gut: Name three things that make the villi an efficient exchange surface?

Answer 40

-Thousands of finger like projections which in increase the surface area where absorbtion takes place -The villi walls are thin and have many capillaries close to the wall providing a good blood supply -Soluble products of digestion can be absorbed into the villi by either diffusion or active transport

Question 41

Exchange in the gut: What similarities do villi and alveoli have?

Answer 41

They both have thin walls, large surface area and good blood supply

Question 42

Exchange in plants: Gases diffuse in and out of leaves through thiny holes called \_\_\_\_?\_\_\_\_\_

Answer 42

Stomata

Question 43

Name the gases and what they do?

Answer 43

-Oxygen ~ needed for respiration and waste products of photosynthesis -Carbon Dioxide ~ needed for photosynthesis and waste product of respiration

Question 44

The plants loose water vapour through the stomata due to?

Answer 44

evaporation

Question 45

How do leaves diffuse the gases?

Answer 45

The leaves are thin and flat. Internal air spaces which help to increase the rate of diffusion

Question 46

What do root hair cells do?

Answer 46

Increase the surface area of roots for the absorbtion of water and mineral ions

Question 47

If the plant is dry what will the stomata do?

Answer 47

It will close to prevent wilting

Question 48

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Answer 48

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Question 49

Transpiration: Explain how water is lost from the leaves

Answer 49

Water goes up the roots passes through plant to leaves. In the leaves water evaportes from the leaf cells and water diffuses out through the stomata.

Question 50

The movement of water through the plant is ?

Answer 50

transpritation stream

Question 51

what causes the plant to dehydrate and dry up ?

Answer 51

Evaparation - more rapid in hot wind bringht places

Question 52

What happens to prevent excessive water loss?

Answer 52

guard cell can close The leaves wilt - leaves hang down and shrivel reducing the surface area

Question 53

By what proces does water vapour move out of the leaves?

Answer 53

Diffusion