B7: Gas exchange, Breathing and Respiration

Question 1

Definition of respiration

Answer 1

process by which energy is released from food.

Question 2

type of respiration

Answer 2

• aerobic
• anaerobic

Question 3

what happens to the energy released from food

Answer 3

it is used to make ATP

Question 4

how is ATP formed?

Answer 4

Energy produced used to combined ADP and phosphate group to form ATP

Question 5

advantages of storing anergy produced from food in the form of ATP?

Answer 5

• energy is released rapidly
• small amount of energy produced for each molecule of ATP to prevent wastage

Question 6

Energy released by ATP is used for?

Answer 6

• manufacture more complex molecules such as protein and DNA
• cell growth and repair
• cell division
• in active transport to move molecules and ions in and out of cells.
• special cell functions such as muscle contraction, and transmission of nerve impulses.

Question 7

Energy released in respiration is used to make (1)___________ and some released as (2)____________

Answer 7

1. ATP
2. Heat

Question 8

equation for aerobic respiration

Answer 8

glucose + oxygen ———–> carbon dioxide + water

Question 9

in which organelle does aerobic respiration take place?

Answer 9

mitochondria

Question 10

how many ATP molecules are produced for each molecule of glucose in aerobic respiration?

Answer 10

38

Question 11

how may moles of ATP are produced for each mole of glucose?

Answer 11

38

Question 12

where does anaerobic respiration take place?

Answer 12

in the cytoplasm

Question 13

how many molecules of ATP are produced for each molecule of glucose in anaerobic respiration

Answer 13

2

Question 14

equation for anerobic respiration in yeasts

Answer 14

glucose ———-> ethanol + carbon dioxide + energy

Question 15

equation for anaerobic respiration in muscle cells

Answer 15

glucose ———-> lactic acid + energy

Question 16

importance of anaerobic respiration in bacteria

Answer 16

bacteria break down organic waste in the abscence of oxygen to form biogas, which is a mixture of 60% methane and 40% carbon dioxide. Biogas is used for fuel.

Question 17

parameters to know when discussing the differences between aerobic and anaerobic respiration

Answer 17

• use of oxygen
• where they occur
• amount of energy released
• the end products
• where glucose is completely broken down or not.

Question 18

what is gaseous exchange?

Answer 18

process by which oxygen diffuses into, and carbon dioxide diffuses out of an organism, through a gaseous exchange surface

Question 19

what is the gaseous exchange surface?

Answer 19

lining across which gases diffuse.

Question 20

examples of respiratory surfaces

Answer 20

alveoli in mamals

gills in fish

mesophyll layer in the leaves in plants

Question 21

what is breathing?

Answer 21

movements in animals that bring oxygen to the gaseous exchange surface and remove carbon dioxide from the gaseous exchange surface.

Question 22

features of gaseous exchange surfaces

Answer 22

• Thin - so that gases can quickly diffuse through them.
• Moist - moist, so that gases can dissolve before diffusing.
• Large surface area - the surface area for gases to diffuse through.
• Good blood supply - the airsacs have a large capillary network so that large volumes of gases can be exchanged.

Question 23

Label the respiratory system

Answer 23

Question 24

Label the respiratory system

Answer 24

Question 25

what is the name pair of membranes that surround the lungs

Answer 25

pleural membranes

Question 26

what is the name of the fluid found between the pleural membrane?

Answer 26

pleural fluid

Question 27

where does gaseous exchange occur in humans?

Answer 27

the lungs

Question 28

which vessel carries blood to the lungs for gas exchange?

Answer 28

the pulmomary artery

Question 29

which vessel carries blood away from the lungs after gas exchange?

Answer 29

pulmonary veins

Question 30

How is air brought into and pushed out of the lungs?

Answer 30

by movements of the diaphram and the interostal muscles connecting the ribs

Question 31

Mechanism of inhalation(inspiration)

Answer 31

* external intercostal muscles contract * internal intercostal muscles relax * ribs and sternum move upwards and outwards * diaphram contracts and flattens * volume inside the lungs and thorax incease * pressure inside the thorax and lungs decrease * air drawn into the lungs due to the decreased pressure

Question 32

Mechanism of exhalation(expiration)

Answer 32

* external intercostal muscles relax * internal intercostal muscles contract * ribs and sternum move downwards and inwards * diaphram relaxes and domes upwards * volume inside the lungs and thorax decrease * pressure inside the thorax and lungs increase * air pushed out of lungs due to the increased pressure in the lungs

Question 33

explain gas exchange in the alveoli

Answer 33

Question 34

composition of the follwing gases in inhaled and exhaled air 1. Oxygen 2. Carbon Dioxide 3. Nitrogen 4. water vapour

Answer 34

1. 21%, 16% 2. 0.04%, 4% 3. 78%, 78% 4. Varoable, saturated

Question 35

where does gaseous excahnge occur in fish

Answer 35

gills

Question 36

where does gaseous exchange occur in flowering plants?

Answer 36

Leaves, stems, roots

Question 37

In flowering plants, the rate of (1)\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ is equal to the rate of (2)\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ at dusk and at (3)\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_. This is called the (4)\_\_\_\_\_\_\_\_\_\_\_\_\_\_.

Answer 37

1. photosynthesis 2. respiration 3. dawn 4. compensation point

Question 38

for gaseous exchange in plants what is the compensation?

Answer 38

when the rate of photosynthesis ans respiration are equal.

Question 39

at dusk an at dawn, why is there no net movement of gases in or out of leaves

Answer 39

because gaseous exchange has reached a compensation point where the rate of phosynthesis and the rate of respiration are the same.

Question 40

when does photosynthesis occur?

Answer 40

when there is sunlight

Question 41

when does respiration occur

Answer 41

all the time.

Question 42

what are the negative effects of smoking cigarettes

Answer 42

* **nicotin addiction.** Nicotine is toxic, it increases heart rate and blood pressure, and increases the risk of stroke and osteoporosis. * **reduced oxygen carrying capacity of the blood** because carbon monoxide combines with some of the haemoglobin. Smokers have decreased ability to exercise, and the foetus does not develop properly due to insufficient oxygen. * **Persistent cough.** Due to increased mucus production and damaged cilia which no longer beat to remove the excess mucus. * **Cancer** of the lung, throat, oesophagus and mouth because ciagrette smoke contains tar and over 60 other substances that cause cancer(carcinogens) * **Emphysema** because the alveoli become damaged and less elastic. * **Chronic Bronchitis** because of continuous irritation and inflammation of the bronchi and bronchioles.

Question 43

Negative Effects of smoking Marijuana

Answer 43

* persistent cough * bronchitis * lung cancer * marijuana addiction * frequent lung infections