Biology Chapter 11

Question 1

Define respiration

Answer 1

A series of metabolic reactions to break down glucose molecules and release energy from them.

Question 2

What are the two types of respiration?

Define each

Answer 2

Aerobic respiration
Uses oxygen to break down glucose into carbon dioxide and water
Anaerobic respiration does not need oxygen, producing alcohol and carbon dioxide or only lactic acid. The energy produced aren’t as much.

Question 3

List the characteristics of gas exchange

Answer 3

1. They are thin
2. Close to an efficient transport system
3. They have large surface area
4. They have good supply of oxygen

Question 4

Explain the steps air go through human breathing system

Answer 4

1. Air enters the body through the nose or mouth
2. Air passes into the trachea (windpipe)
3. Trachea divides into left and right bronchus. Each bronchus goes into the lung and into smaller tubes called bronchioles.
4. Air will reach the end of the tube into alveoli (tiny air sacs) where gas exchange occur

Question 5

Describe an alveoli

Answer 5

Tiny capillaries are closely wrapped around the outside of alveoli to allow oxygen to diffuse into the blood and carbon dioxide to the other way.

Question 6

List the characteristics of the walls of alveoli

Answer 6

1. Very thin, one cell thick
2. Excellent transport system, blood is moving
3. Large surface area
4. Good supply of oxygen

Question 7

Explain the inhalation process

Answer 7

The internal intercostal muscle relax while the external intercostal muscle contract, this pulls the rib up and out while the diaphragm also contracts that force it downwards. This will increase the volume of the thorax, which makes the pressure inside our body lower than the atmospheric pressure. The pressure difference causes air to move from high pressure to low pressure.

Question 8

Explain the exhalation process

Answer 8

Both intercostal muscle relax and the diaphragm moves back and relax, this decreases the volume of the thorax. The pressure increase causing air to forcefully excrete from high pressure to low pressure.

Question 9

The ______ the volume, the ______ the pressure

The ______ the volume, the ______ the pressure

Answer 9

The larger the volume, the lower the pressure

The smaller the volume, the higher the pressure

Question 10

What are goblet cells?

Answer 10

Goblet cells make a liquid containing water and mucus which evaporates and moistens the air.

Question 11

What is epiglottis

Answer 11

Epiglottis is a piece of cartilage on top of the trachea which closes the trachea and stops food going down the wrong way

Question 12

What is larynx?

Answer 12

Larynx is the voice box that contains vocal cords located below the epiglottis.

Question 13

What are the muscles that helps us breathe?

Answer 13

Both intercostals muscles and diaphragm

Question 14

Define gas exchange

Answer 14

The exchange of gas across a respiratory surface

Question 15

Define breathing

Answer 15

Muscular movements which keep the respiratory surface supplied with oxygen

Question 16

Explain what happens to our breathing rate when exercising and what causes that to happen.

Answer 16

1. When exercising, the muscles uses and need a lot of oxygen to make energy. The cells in the muscles will combine glucose molecules and oxygen as fast as they can.
2. To take a lot of oxygen, you breath deeper and faster while the heartbeat fasten to transport the oxygen.
3. Eventually both the lungs and heart can not supply and faster, it reaches a limit.
4. Extra energy is needed, where anaerobic respiration will occur.
5. After the exercise, there will be a lot of lactic acid in the blood. To get rid of it, it is broken down by combining it with oxygen in the liver.
6. After exercising, the breathing rate will still be fast and deep while the heart beat is still high because it still needs oxygen to break down the lactic acid.
7. Not until all the lactic acid has been used up, does your breathing and heartbeat will return to normal.

Question 17

What is the role of brain in breathing?

Answer 17

Brain controls the breathing rate. It monitors the pH of the blood that flows through it. When blood has a lot of carbon dioxide or lactic acid concentration, the pH will fall. Brain will sense this and send nerve impulses to stimulate the diaphragm and intercostal muscles for them to contract harder and more often.

Question 18

What are cilia?

Answer 18

Found along trachea and bronchus, tiny hair like projections that traps dust within the mucus and move the mucus back up to the throat.