Spring Term

Question 1

What is the dependent variable?

Answer 1

The dependent variable is the one that you measure.

Question 2

What is the independent variable?

Answer 2

The independent variable is the one that you change.

Question 3

What is a control variable?

Answer 3

The control variable(s) is the one that you keep the same throughout the experiment.

Question 4

What is breathing?

Answer 4

Breathing is bringing air in and out of the lung. Where oxygen transfers into the bloodstream and waste gases are transferred back out.

Question 5

What is respiration?

Answer 5

Respiration is using oxygen and glucose to produce energy.

Question 6

What is the difference between breathing and respiration?

Answer 6

The difference between breathing and respiration is that breathing is only gas exchange whereas respiration is using the oxygen and glucose to produce.

Question 7

What is the equation for aerobic respiration?

Answer 7

Oxygen + Glucose -> Carbon dioxide + water + (energy)

Question 8

What does the equation for respiration show?

Answer 8

The equation for respiration shows that glucose and oxygen are needed to produce energy, and the byproducts are water and carbon dioxide.

Question 9

What is an application of respiration in building molecules?

Answer 9

An example is growing or healing because you need a lot of energy to make new molecules for these activities.

Question 10

What is oxygen debt?

Answer 10

Oxygen debt is where you are respiring but you don’t have enough oxygen. This is called anaerobic respiration. Instead you turn glucose into lactic acid which produces energy but makes muscles stiff. After you finish you need to take in oxygen to turn the lactic acid into energy. Thus resulting in you breathing in deeply.

Question 11

What is the equation for anaerobic respiration?

Answer 11

Glucose -> lactic acid + energy

Question 12

What is the mechanism of breathing in?

Answer 12

When you breath in, intercostal muscles contract, your ribs move up, diaphragm muscles contract, the diaphragm lowers, volume in the chest increases and the pressure in the chest increases, air pressure in the lungs is lower than the atmospheric pressure and air rushes into the lungs.

Question 13

How does a change in pressure help you breath?

Answer 13

A change in pressure outside the lungs makes the lungs want to have the same pressure so either is takes in more air or pushes air out. The pressure is controlled by the diaphragm.

Question 14

What is lung volume?

Answer 14

Lung volume is the capacity of the lung, so how much air it can hold.

Question 15

How could you measure lung volume?

Answer 15

• You can use a Spirometer
• You can use a Lung Volume Bag
• You can use water displacement

Question 16

What is the trachea?

Answer 16

The trachea is also known as the windpipe. The trachea is the main airway leading to the lungs from the larynx. The trachea is strong and flexible due to the rings of cartilage around it keeping the airway open at all times.

Question 17

What is the larynx?

Answer 17

The larynx is also known as the voice box. It is a cavity in the opening of the trachea where it meets the pharynx.

Question 18

What is the pharynx?

Answer 18

The pharynx is the cavity in the throat at the back of your mouth, where the upper part (nasopharynx) is an airway leading to the trachea, but the other passage where food goes is the oesophagus.

Question 19

What is the bronchus?

Answer 19

The bronchus is one of the two tubes (bronchi) branching off of the trachea carrying air into each lung. To stop them from collapsing while breathing they have rigid cartilage rings around them. There are gland there that produce mucus to collect any unwanted particles.

Question 20

What are ribs?

Answer 20

Ribs are bones coming out of the spine and form a rib cage that can expand easily for breathing by movement of intercostal muscles. The rib cage protects vital organs such as the heart and lungs.

Question 21

What are alveoli?

Answer 21

Alveoli are tiny air sacs in the lungs where gas exchange takes place. This is because they have thin walls making it easy for the gases to get through.

Question 22

What is the mechanism of breathing out?

Answer 22

When you breath out intercostal muscles relax, ribs move down, diaphragm muscles relax and the diaphragm raises, the volume in the chest decreases and the pressure in the chest decreases, air pressure in the lungs is greater than the atmospheric pressure and air rushes out of the lungs.

Question 23

What is the lung?

Answer 23

The lung is a large, delicate spongy organ in which gaseous exchange takes place. In humans there are two lungs, and lungs are protected by a rib cage of 12 pairs of bones.

Question 24

What is a diaphragm?

Answer 24

The diaphragm is a sheet made from muscle and tendon and separates the thorax from the abdomen. It is arched when resting and when contracted changes the pressure around the lung forcing air to rush into the lung to breathe.

Question 25

What are bronchioles?

Answer 25

Bronchioles are smaller tubes in the lung leading off the bigger bronchus that lead to the alveoli. They transport gases in and out of the lung.

Question 26

What features help gas exchange?

Answer 26

Alveoli have thin walls and capillaries meaning that there is a short diffusion distance. The lining is moist so the gases can dissolve. Breathing and circulation help maintain a diffusion gradient (good blood supply). Alveoli have an enormous surface area to take in lots of oxygen and carbon dioxide.

Question 27

How has the understanding of smoking changed over time?

Answer 27

Before the 1950s people recommended smoking, especially because their doctors smoked. It wasn’t seen as bad for you, people thought it was good for you. In 1954 Ernst L. Wonder was awarded a Nobel Prize for finding evidence of a link between smoking and Lung cancer.

Question 28

What is fermentation?

Answer 28

Fermentation is the process by which sugars are broken down by bacteria or yeasts, in the absence of oxygen. This is anaerobic respiration.

Question 29

Why is respiration important?

Answer 29

Respiration is important because it produces energy, you need energy in order to survive.

Question 30

What are the physical effects of exercise on the breathing system? (Describe and explain)

Answer 30

- During exercise, your breathing rate and depth of breathing increase, resulting with more oxygen in your blood. - If you exercise regularly the diaphragm and intercostal muscles will get stronger. - This means that your chest cavity can open up more when you breath in, so your lung volume becomes higher.

Question 31

What is the long term physical effects of exercise on the breathing system? (Describe and explain)

Answer 31

Over time, regular exercise can cause an increase in the number and size of small blood vessels in your lungs and in the number of alveoli. This means that gas exchange becomes more efficient.

Question 32

What are the physical effects of asthma on the breathing system? (Describe and explain)

Answer 32

- Asthmatics have lungs that are too sensitive to certain things. - When an asthmatic breathes these things in, the muscles around the bronchioles contract, narrowing the airways. - The lining of the airways becomes inflamed and fluid builds up in the airways, making it hard to breath (asthma attack).

Question 33

What are symptoms of an asthma attack, and how do asthmatics end them?

Answer 33

``` Symptoms: -difficulty breathing -wheezing -a tight chest When symptoms appear, asthmatics can I use an inhaler containing drugs that open up the airways ```

Question 34

What are the physical effects of smoking on the breathing system? (Describe and explain)

Answer 34

Cigarettes contain around 4000 chemicals, of which 400 are toxic, including carbon monoxide and tar. This is bad for your lungs and can cause some cancers. They also contain nicotine, which is addictive meaning you struggle to stop smoking.

Question 35

Why is tar bad for you, and what effects it has on you?

Answer 35

- Tar covers the cilia on the lining of the airways - The damaged cilia can’t get rid of mucus properly - The mucus sticks to the airways making you cough more - this is known as a smokers cough - The damage builds up and could lead to bronchitis and emphysema, making it harder to breathe - Tar contains carcinogens (substances that can cause cancer). - Smoking causes cancer in lungs, throat and mouth.

Question 36

What is bronchitis?

Answer 36

Bronchitis is a disease that inflames the lining of the bronchi, making it harder to breathe.

Question 37

What is emphysema?

Answer 37

Emphysema is a disease that destroys the air sacs in the lungs, making it harder to breathe.

Question 38

Why do some sports use more aerobic or more anaerobic respiration?

Answer 38

In some sports (swimming or running or sprinting) you respire anaerobically because your body needs so much energy but you can’t get the oxygen fast enough to respire aerobically. Whereas other sports you can respire aerobically because you aren’t using too much energy up, so you manage to breath enough.

Question 38

What is anaerobic respiration like in humans?

Answer 38

In humans anaerobic respiration produces lactic acid. Lactic acid can build up in your muscles during exercise and can be painful.

Question 39

What is anaerobic respiration like in different organisms?

Answer 39

In microorganisms like yeast, anaerobic respiration produces carbon dioxide and ethanol (alcohol). When anaerobic respiration produces ethanol it is called fermentation. Fermentation is the process used to make beer.