Gaseous exchange Topic 8 1st year

Question 1

What is the difference between aerobic and anaerobic respiration?

Answer 1

Aerobic uses oxygen
Anaerobic doesn’t use oxygen

Question 2

What is the word equation for aerobic respiration?

Answer 2

Glucose + oxygen = carbon dioxide + water + energy

Question 3

What is carbon dioxide acting us in the word equation?

Answer 3

A waste product that needs to be removed from the body

Question 4

How does the body keep the balance of the gases in and out of the body regarding oxygen and carbon dioxide?

Answer 4

By the process of gaseous exchange includes the movement in and out of these gases through a concentration gradient . (Homeostasis)

Question 5

Not all organisms have the same respiratory organs to maintain the balance of gases in and out of the body.

Mention some organisms and mention the type of respiratory surface that they make use of to keep the balance of gases in and out of the body.

Answer 5

Insects have trachea
Fish have gills
Mammals, birds, and reptiles have lungs

Question 6

How do small organisms carry out gaseous exchange and what type of surface area do they have?

Answer 6

Small organisms like bacteria use their entire body surface for gaseous exchange,this is because they have a large surface area to volume ratio.

Question 7

How do large organisms carry out gaseous exchange and what type of surface area do they have?

Answer 7

Since large organisms are more complex initially they have a small surface area to volume ratio,this makes it impossible to reach every single cell in the body,so more oxygen is needed for the organism to survive.

In order to reach every single cell in the body specialised organ systems must be present like the lungs,which increase the surface area. (A ventilation system is needed which works with the circulatory system which ensures that oxygen is pumped throughout the whole body

Question 8

Define breathing

Answer 8

Breathing is the process by which air moves into and out of the lungs through the mouth or the nose, due to muscle contraction and then removed from the lungs due to muscle relaxation. Oxygen is inhaled and carbon dioxide is exhaled.

Question 9

Define cellular respiration

Answer 9

The chemical process by which energy is released from food in order to keep the cell alive. This takes place in every living cell

Question 10

What is gaseous exchnage?

Answer 10

This takes pace at the respiratory surface. Ventilation takes place which is the movement and exchange of oxygen and carbon dioxide into and out of the lungs

Question 11

Where does gas exchange take place in humans?

Answer 11

In the lungs in the alveoli.

Once oxygen is taken in diffusion of oxygen and carbon dioxide takes place in the alveoli. (Ventilation)

Question 12

What is the ion present in the blood which makes oxygen transport efficient

Answer 12

Haemoglobin

Question 13

How is carbon dioxide transported out of the body?

Answer 13

Bicarbonate ions

Question 14

Mention 5 characteristics of a respiratory surface.

Answer 14

1) Large surface area to volume ratio:
this makes it more efficient and oxygen can be reached throughout the whole body.
2) Permeable to gaseous substance: it would be useless to have a respiratory surface that is not permeable
3) Thin structures: diffusion of gases is quicker and more efficient
4) Moist: diffusion is faster than in water (gases dissolve)
5) Rich blood supply: maintain a diffusion gradient and transport the gases throughout the whole body
6)Ventilation: ventilation of the lungs helps to maintain a steep diffusion gradient.

Question 15

Where are the lungs located in mammals?

Answer 15

Thorax

(positioned behind te heart)

Question 16

Mention 2 things that protect the lungs and mention how.

Answer 16

The rib cage and the pleural membrane which contains pleural fluid.

The pleural fluid prevents friction in the lungs and the wall of the thorax

Question 17

What is the muscular tissue that is located underneath the lungs?

Answer 17

Diaphragm

Question 18

What are the muscles that aid in breathing?

Answer 18

Intercoastal muscles are located between the ribs.
They move up and down

Question 19

What is the first part of the respiratory system and why is it important?

Answer 19

Nasal cavity.

Its is important because the air is moistened,filtered and this is where nay harmful substances like dust or microbes are trapped because mucous is secreated by globlet cells

Question 20

Mention the parts from where air passes through.

Answer 20

Nasal cavity, throat,voice box and trachea

Throat : pharynx
Voice box: larynx

Question 21

What is the epiglottis?

Answer 21

The epiglottis is the muscle that closes the pipe through the trachea during swallowing to prevent the entry of food in the respiratory tract. If food enters chocking occurs. Ensures that food goes down the stomach and the osepahagus.

Question 22

What is the trachea made up of and how does this help the trachea with its functioning?

Answer 22

Made up of rings of cartilage and prevents the trachea from collapsing during breathing

Question 23

How is the trachea divided?

Answer 23

The trachea branches into 2 bronchi.
The bronchi branch again into smaller branches called bronchioles
Then te bronchioles branch into the alveoli which are te respiratory surface where gaseous exchnage take place

Question 24

What are goblet cells?

Answer 24

Globlet cells are cells which are located in the nasal cavity which produce mucous. The mucous is responsible for trapping dust and foreign bodies.
Then the trapped dust and particles are beaten upwards by the cilia and removed. They are either sneezed or coughed up

Question 25

What are cilia?

Answer 25

Cilia are tiny hairy-like structures located in the nasal cavity. They beat up mucous-containing dust and foreign bodies through the nasal cavity where they sneeze.

Question 26

True or false.
Cilia and goblet cells are found in the nasal cavity as well as in the bronchioles and bronchi of the lungs

Answer 26

True

Question 27

What is the epithelium called in the nasal cavity?

Answer 27

Ciliated epithelium

Question 28

True or false.
Cilia do not move.

Answer 28

False.
Cilia are constantly moving in a wave-like action to remove any foreign bodies up into the nasal cavity preventing them from reaching the lungs.

Question 29

What is ventilation?

Answer 29

Movement of air into and out of the lungs

Question 30

How can we also call inhalation and exhalation?

Answer 30

Inhalation: active inspiration
Exhalation: passive expiration

Question 31

What is the role of the diaphragm?

Answer 31

It separates the thorax from the abdomen

Question 32

What happens during inhalation?

Answer 32

Inhalation:lungs are being filled with oxygen

Volume in the lungs increases + pressure decreases
The diaghpraghm contracts and flattens.
The intercostal muscles contract and the rib cage moves up and outwards

Question 33

What happens during exhalation?

Answer 33

Exhalation: carbon dioxide is exhaled

Volume in lungs decreases + pressure increases
The diaphragm relaxes and bulges upwards
The intercostal muscles relax and the rib cage moves down and inwards

Question 34

Define gaseous exchange.

Answer 34

The exchange of oxygen and carbon dioxide takes place between the air and the blood vessels in the lungs.

This takes place by simple diffusion in the alveoli

Question 35

What can we say that forms when oxygen diffuses into a red blood cell to be transported into the cells,in the alveolus?

Answer 35

Oxy-haemoglobin forms

Question 36

What does carbon dioxide form when it is carried out of the body?

Answer 36

hydrogen carbonate ions

carried as bicarbonate ions

Question 37

After oxygen binds with haemoglobin in the red blood cells,how is it transported?

Answer 37

Oxygen will be transported to the heart via the pulmonary vein, then the aorta will transport the oxygenated blood to all the cells that need oxygen.

Question 38

How is carbon dioxide transported in the blood?

Answer 38

Carbon dioxide binds with red blood cells as hydrogen carbonate ions

Question 39

Which blood vessels bring deoxygenated blood from the heart to the lungs?

Answer 39

The pulmonary artery

Question 40

Draw a diagram of an alveolus (gaseous exchnage)

Question 41

How is carbon dioxide exhaled out of the body? Explain the entire process.

Answer 41

In tissues, carbon dioxide (CO2) combines with water (H2O) inside red blood cells, facilitated by the enzyme carbonic anhydrase, to form carbonic acid (H2CO3).
Carbonic acid dissociates into bicarbonate ions (HCO3-) and hydrogen ions (H+).
Bicarbonate ions are transported in the bloodstream to the lungs.
In the lungs, bicarbonate ions re-enter red blood cells, and carbonic acid reforms.
Carbonic acid then breaks down into CO2 and H2O.
CO2 is released from red blood cells into the alveoli of the lungs.
Finally, CO2 is exhaled out of the body during expiration.

Question 42

True or false.
Carbon dioxide is more soluble than oxygen so when it is transported in the blood the majority of it is located in the plasma.

Answer 42

True

Question 43

True or false. The majority of carbon dioxide is transported as bicarbonate ions

Answer 43

True

Question 44

Which part of the brain is controlling the carbon dioxide concentration in the blood?

Answer 44

Medulla oblongata

Question 45

Explain why during exercise cells respire more.

Answer 45

This is because during excercise more oxygen must be delivered to the cells and more carbon dioxide must be removed. This is why the medulla oblongat the part of the brain controls carbon dioxide levels conceentration in the blood,causing deeper breaths to be taken.

Question 46

Compare the concentration of gases that we breath in and that we breath out.

Answer 46

Nitrogen is very unreactive we inhale it but we exhale all of it. We dont use any of it either

Oxygen: we inhale it and use it
we do not use up all of the oxygen that we breath,we also exhale oxygen too.

carbo dioxide: we exhale more of it. carbon dioxide is toxic in the body it needs to be removed

Question 47

Mention a health hazard connected with breathing and explain the damage it causes

Answer 47

Smoking

Smoking damages the heart and the lungs.

Tobacco smoke contains chemicals which are harmful to our health: Nicotine,carbon monoxide and tar

Nicotine: addictative chemical. Increases heart rate and blood pressure
Tar:causes cancer
carbon monoxide a gas that binds heavily with haemoglobi in red blood cells which reduces the level of oxygen in the blood.

Question 48

Mention 2 other respiratory diseases

Answer 48

Bronchitis and emphysema

Question 49

Explain bronchitis

Answer 49

Inflammation of the lungs.

This is caused by excess mucous being produced in the lungs and causes problems in absorbing oxygen.

Cilia are killed due to the cigarette smoke.

Symptoms : constant coughing,which is a natural mechnaism that removes foreign bodies and irritants from our lungs.

Question 50

Explain emphysema

Answer 50

Mainly affects the alveoli. There is an over inflation of the alveoli

Symptoms include: shortness of breath and cough

Usually people with this disease die of respiratory failre and some others die of heart failure. This is because the heart is overowkred due to the lack of oxygen that there is in the body,so the heart becomes overoworked to try and encompass for the lack of oxygen,but it beomes enlarged leading to heart failure.

People with emphysema have one large air sac instead of many small ones.

Emphysema gradually develops. Exposure to cigarette smoke increases the chance of developing emphysema

Treatment for empphysema:

Quitting smoking
Lung transplant
Antiobiotics if there is a bacterial infection
Excercise to help strengthen the muscles used in breathing.

Question 51

Exlplain lung cancer

Answer 51

Cancer is the growth of abnormal cells that grow out of control which can form lumps called tumours.

Question 52

Explain heart disease

Answer 52

Nicotine and carbon monoxide make the blood clot more easily. This can block the arteries resulting in less oxygen to the heart muscle which damages the heart. + Passive smoking

Question 53

Draw a diagram of the respiratory system