Respiration

Question 1

Define respiration

Answer 1

The chemical reactions that break down nutrient molecules in living cells to release energy

Question 2

Define aerobic respiration

Answer 2

the release of a relatively large amount of energy in cells by the breakdown of food substances in the presence of oxygen.

Question 3

Define anaerobic respiration

Answer 3

the release of a relatively small amount of energy by the breakdown of food substances in the absence of oxygen.

Question 4

State the word equation in the microorganism yeast

Answer 4

glucose- alcohol + carbon dioxide

Question 5

Describe the effect of lactic acid in muscles during excercise

Answer 5

When exercise vigorously, blood cannot supply enough oxygen for aerobic respiration, leads to anaerobic respiration. Lactic acid builds up in the muscles-cramps. When you stop exercising, you breathing hard to get oxygen to break down lactic acid.

Question 6

Describe the role of anaerobic respiration in yeast during brewing.

Answer 6

• Yeast is dissolved in a warm liquid containing sugar maltose
• Yeast respires anaerobically by fermentation
• This process produces ethanol making the drink alcoholic
• Co2 makes the drink fizzy

Question 7

Explain the role of mucus and cilia in protecting the gas exchange system from pathogens and particles.

Answer 7

• The lining contains two kinds of cells: Goblet cells and ciliated cells;
• Goblet cells make sticky, slimy mucus;
• Bacteria in the air and dust particles get trapped in the mucus;
• Ciliated cells have tiny, microscopic hair on them called cilia;
• The cilia beat in unison, and sweep the mucus upwards, towards the back of the throat.

Question 8

Describe the effects of tobacco smoke and its major toxic components (tar) on the gas exchange system

Answer 8

A carcinogen - increases the risk of lung cancer;, increasing mucus production and paralyzing and damaging cilia, causing bronchitis.

Question 9

Explain the effects of physical activity on rate and depth of breathing.

Answer 9

During exercise, the volume inhales(depth) increases
-The total lung volume is greater than the vital capacity because some air always remains in the lungs (otherwise the lungs would collapse and the alveoli walls would stick together)
Breathing rate and depth increase to absorb more oxygen for the muscles as exercising muscles need to respire more to get more energy.

Question 10

List the features of gas exchange surfaces in animals

Answer 10

-Wall of the alveolus is thin to allow gas diffuse quickly
Moist to prevent the cells from drying and to allow gases to dissolve;
Large surface area , so that a lot of gas can diffuse across at the same time;
High concentration gradient - maintained by the movement of air & blood.

Question 11

Describe the effects of tobacco smoke and its major toxic components (nicotine) on the gas exchange system

Answer 11

Addictive; increases heart rate & blood pressure

Question 12

Describe the effects of tobacco smoke and its major toxic components (carbon monoxide) on the gas exchange system

Answer 12

A poisonous gas; combines with hemoglobin in RBC, preventing them from transporting oxygen

Question 13

Describe the effects of tobacco smoke and its major toxic components (smoke particles) on the gas exchange system

Answer 13

Irritate the air passages, causing inflammation & increased mucus production, resulting in chronic bronchitis

Question 14

Define vital capacity

Answer 14

The maximum amount of air breathed in and out in one breath