Science - Breathing & Respiration Unit

Question 1

What is Aerobic Respiration?

Answer 1

The process through which oxygen is used to release energy stored in glucose

Question 2

Where do we get glucose from?

Answer 2

We get glucose from digesting food

Question 3

What is the equation for respiration?

Answer 3

Equation Oxygen + Glucose –> Carbon Dioxide + Water + (Energy)

Question 4

Why do we need to respire?

Answer 4

We need to respire to get Heat and Energy

Question 5

What changes the size of the lungs?

Answer 5

Muscles between the ribs and in the diaphragm change the size of the lungs.

Question 6

Describe Inhalation

Answer 6

Inhalation: Pressure in the lungs is reduced. Atmospheric pressure is greater and air flows in. Muscles between and attached to the ribs contracts and pull the ribs up and out. The chest becomes bigger

Question 7

When inhaling: The muscles in the diaphragm ______ and moves it ____

Answer 7

The muscles in the diaphragm contracts and moves it down

Question 8

What is the job of Mucus?

Answer 8

Mucus traps dust and dirt

Question 9

What is the function of cilia

Answer 9

Tiny hairs on some cells, called cilia, sweep the dirt out of the lungs and into the mucus.

Question 10

Describe Gas Exchange

Answer 10

• Oxygen from the air enters the blood
• At the same time some carbon dioxide from the blood enters the lungs
• Gas exchange occurs by diffusion

Question 11

What is Alveoli?

Answer 11

• Small pockets with a large surface area
• Walls are only one cell thick
• Blood capillaries surrounding alveoli also have thin walls

Question 12

Why is large surface area useful for Alveoli?

Answer 12

Larger surface area let diffusion happen faster

Question 13

What does Aerobic mean?

Answer 13

Aerobic means ‘needing oxygen’

Question 14

Describe Aerobic Respiration

Answer 14

• Aerobic respiration releases energy to do work and to keep our bodies warm
• Aerobic respiration and combustion are nearly the same, but combustion is a faster reaction.

Question 15

How does oxygen reach the blood?

Answer 15

The oxygen diffuses from the lungs into the blood

Question 16

Describe The transport of oxygen from lungs to cells

Answer 16

The oxygen enters the red blood cells in the blood and stick to the haemoglobin

• Blood is pumped from the lungs to the heart
• The heart then pumps the blood to rest of the body
• The blood moves inside veins/arteries, which divide into much smaller capillaries

Question 17

What happens inside the capillaries in detail?

Answer 17

In the capillaries, the oxygen leaves the red blood cells and dissolve in the blood plasma

• The plasma leaks out through very small holes in the capillaries and form tissue fluid
• The tissue fluid carries the oxygen to the cells
• Waste products( CO2) from the cells dissolve in the tissue fluid and return back to the blood in the capillaries
• The capillaries are connected to veins, which carry blood back to the heart and then to the lungs.

Question 18

What happens during exercise?

Answer 18

When you exercise, your muscles work harder

• You need more respiration to release energy
• Your breathing rate will increase
• You breathe more to take in more oxygen
• Your heartbeat will increase
• Your heart works harder to pump more blood to your muscles

Question 19

What happens when you have lack of oxygen?

Answer 19

Without oxygen cells will die
E.g. When it is very cold, your blood vessels become narrow to prevent heat loss so less oxygen goes to cells and cells die. This is called frostbite

Question 20

List all the chemicals in ciggarete smoke and the harm they cause

Answer 20

nicotine - makes arteries narrower, causes heart disease, addiction
tar - can cause cancer, coats lungs reducing surface area, can cause alveoli to break apart (emphysema)
carbon monoxide - stops red blood cells carrying so much oxygen
high temperature of smoke - stops cilia working so lungs are not cleaned and mucus collects

Question 21

What happens in heart disease

Answer 21

Blood vessels supplying oxygen to the heart muscle become narrow, because of a fatty substance (cholesterol) inside it

• This reduces blood flow to the heart muscles
• The result is a heart attack

Question 22

What happens if you hold your breathe?

Answer 22

If you hold your breath:

• the carbon dioxide in your blood increases
• At a point, your brain will make you start breathing again
• Haemoglobin in red blood cells store oxygen
• Your muscle cells can also store some oxygen
• After holding your breath, you breathe faster to get rid of the extra carbon dioxide in your blood

Question 23

What is anaerobic exercise?

Answer 23

When you exercise very hard, oxygen is used faster than it can be replaced.
- This is called anaerobic exercise

Question 24

Glucose → ______ ____

Answer 24

Glucose → lactic acid

Question 25

What is EPOC?

Answer 25

EPOC = excess post-exercise oxygen consumption

• EPOC is also called oxygen debt
• Lactic acid from muscles is carried back to the liver, in the blood
• The lactic acid is broken down to glucose
• This process uses a lot of energy
• Extra oxygen needed is called EPOC

Question 26

What happens after exercise?

Answer 26

Energy is used to change lactic acid to glucose

• You will use more energy for a faster heartbeat
• You will use more energy for faster breathing
• This will continue until you have given back the extra oxygen – taken from other places in the body

Question 27

What are lactic acids and when + where do they form?

Answer 27

1. Lactic Acids is a type of acid in your muscles formed as crystals after a shortage of oxygen
2. Lactic Acids form at the muscles
3. Lactic acids form when the glucose doesn’t get enough oxygen in respiration
4. The Lactic acids are broken down in the liver.

Question 28

Inhaled air contains: (the air you breathe in)

Answer 28

• more oxygen used to create energy
• less carbon dioxide than exhaled air
• less water vapor than exhaled air
• lower temperature air
• same nitrogen as exhaled air

Question 29

Exhaledair contains: (the air we breathe out)

Answer 29

• more carbon dioxide produced as a waste product of energy production
• less oxygen as it has been used in respiration
• more water vapor than inhaled air
• higher temperature air – body temperature 37 degrees C
• same nitrogen as inhaled air