Gas Exchange In Plants And Humans

Question 0

What do plants take in from the air during photosynthesis?

Answer 0

Carbon dioxide

Question 1

How do plants exchange gases?

Answer 1

By diffusion

Question 2

What gas do plants take in from the air in respiration?

Answer 2

Oxygen

Question 3

When a plant is photosynthesising does it use up more carbon dioxide or oxygen?

Answer 3

Carbon dioxide

Question 4

When a plant photosynthesises there is little carbon dioxide in the leaf. How does the plant get more carbon dioxide in the leaf?

Answer 4

Carbon dioxide moves into the leaf by diffusion as there is a higher concentration outside the leaf than inside the leaf

Question 5

What does a plant do whilst photosynthesising at the same time?

Answer 5

Respires

Question 6

What is some of the oxygen produced as a waste product in photosynthesis used for ?

Answer 6

Some is used for respiration

the rest diffused out of the leaf

Question 7

Does photosynthesis happen in the day or the night of Both?

Answer 7

Only the day because photosynthesis needs light

Question 8

Does respiration happen in the day or at night or both?

Answer 8

Both reparation happens in the day and night

Question 9

In the day is there a net release of oxygen or carbon dioxide in a plant?

Answer 9

Oxygen

Question 10

In the day is there a net take in if carbon dioxide or oxygen in a plant?

Answer 10

Carbon dioxide

Question 11

At night is there a net take in of oxygen or carbon dioxide in a plant ?

Answer 11

Oxygen

Question 12

At night is there a net release of oxygen or carbon dioxide in a plant?

Answer 12

Carbon dioxide

Question 13

Name 4 ways a leaf is adapted for efficient gas exchange

Answer 13

They are broad- large surface area for diffusion

Thin- gases can easily diffuse

They have stomata- let gases diffuse in and out

They have air spaces - increase surface area and oxygen and carbon dioxide can move easily between cells

Guard cells- opens and closes for efficient gas exchange

Question 14

What colour is hydrogen carbonate solution at the start?

Answer 14

Orange

Question 15

What colour is hydrogen carbonate solution when there is increase levels of carbon dioxide?

Answer 15

Yellow

Question 16

What colour is hydrogen carbonate solution when the level of carbon dioxide decreases?

Answer 16

Purple

Question 17

Describe an experiment to show how light effects gas exchange in a plant

Answer 17

1. Add hydrogen carbonate solution to 4 test tubes
2. Add a leaf to 3 test tubes and put a bung on to stop the leaves falling
3. Wrap a test tube in aluminium foil
4. Put a gauze around another test tube
5. Place test tubes in light
6. Leave for an hour then observe results

Question 18

What are the results of the 4 test tubes used to experiment how light effect gas exchange?

Answer 18

Test tube with no leaf- remains orange

Test tube with leaf and foil( no light) -turns yellow, respiration happens, no photosynthesis, carbon dioxide increases

Test tube with leaf and gauze- remains orange, some respiration and some photosynthesis , carbon dioxide levels remain the same

Test tube with leaf (exposed to light) - turns purple , photosynthesis happens more than respiration so carbon dioxide levels decrease

Question 19

What is the thorax?

Answer 19

The top part if the body (where lungs are) and needed for breathing and separated by diaphragm

Question 20

What are the lungs protected by?

Answer 20

Rib cage

Question 21

How does gas enter the body?

Answer 21

Through the mouth

Question 22

How does the oxygen enter the blood? ( name the body parts in order)

Answer 22

Mouth
Trachea
Bronchi (bronchus)
Bronchioles
Alveoli
Blood

Question 23

What are bronchi and bronchioles?

Answer 23

Bronchi are the 2 tubes that the trachea splits into

Bronchioles are the branches off the bronchi

Question 24

What happens to the intercostal muscles, diaphragm and thorax when we breathe in?

Answer 24

Intercostal muscles contract Diaphragm contracts and flattens Thorax volume increase and pressure decreases

Question 25

What happens to the intercostal muscles, diaphragm and thorax when we breathe out?

Answer 25

Intercostal muscles relax Diaphragm relaxes and moves up Thorax volume decreases

Question 26

Describe an experiment to show how exercise effects breathing rate

Answer 26

1. Sit still for 5 mins 2. Now count how many breaths you take in 1 minute 3. Now do 5 mins of exercise on a treadmill 4. And count your breaths in a minute 5. Make other people do the same experiment to get a wide range of how exercise effects breathing rate

Question 27

Why does breathing rate increase when we do exercise?

Answer 27

Because the muscles are using up more energy so they are respiring more so we need to take in more oxygen and remove more carbon dioxide from the body

Question 28

What are the alveoli?

Answer 28

Little air sacs in the lungs where has exchange happens

Question 29

Does the blood passing next to the alveoli have a higher concentration of carbon dioxide that in the alveoli or lower concentration than in the alveoli ?

Answer 29

Blood has a higher concentration if carbon dioxide

Question 30

Does oxygen diffuse out of blood or alveolus?

Answer 30

Diffuses out of alveoli as there is a higher concentration in the alveoli than in the blood ( diffusion higher to lower concentration)

Question 31

What happens when the blood with oxygen in reaches cells in the body?

Answer 31

Oxygen is released from red blood cells and carbon dioxide diffused out of cells into blood

Question 32

Name 4 ways alveoli are adapted for their function if gas exchange

Answer 32

Millions of them- increased surface area for gas exchange Permeable walls- easy for gases to diffuse through Good blood supply- high concentration of gases maintained Thin walls( one cell thick) - easy for gases to diffuse through- short distance Moist lining- easy for gases to dissolve

Question 33

Name 4 products found in cigarettes

Answer 33

``` Tar Tobacco Carcinogens Carbon monoxide Nicotine ```

Question 34

What do carcinogens cause?

Answer 34

Cancer

Question 35

How do cigarettes and smoking cause emphysema ?

Answer 35

They damage walls of alveoli This reduces surface area for gas exchange Therefore having shortness of breath

Question 36

What are the dangers of tar in the body?

Answer 36

Tar is a treacle like substance which damages the cilia as it collects on them. Cilia are then damaged and cause chest infections as mucus can't be removed by damaged cilia Tar causes bronchitis- irritates bronchi/bronchioles causing them to produce mucus but it can't be cleared by damaged cilia

Question 37

What are the risks if carbon monoxide in the blood?

Answer 37

Reduces oxygen in the blood Causes increase heart rate to try and get more oxygen in the blood Causes high blood pressure causing damaged artery walls Causes blood clots Increased risk of coronary heart disease