Biology: Respiration Flashcards Preview

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Flashcards in Biology: Respiration Deck (20)
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1
Q

Define Respiration

A

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

2
Q

State Word Equation & Chemical Equation for Aerobic Respiration

A

Glucose + Oxygen –> Carbon Dioxide + Water + Energy

C6H12O6 + 6O2 –> 6CO2 + 6H2O

3
Q

Define Aerobic Respiration

A

Release of relatively large amount of energy in cells by breakdown of food substances in the presence of oxygen

4
Q

State Uses of Energy in Body of Humans

A

Muscle contraction, protein synthesis, cell division, growth, the passage of nerve impulses and the maintenance of a constant body temperature

5
Q

AGS not specifically IG content:

Air Path

A
Nose or mouth
Trachea
Bronchi
Bronchioles
Alvelioli
6
Q

How Do You Test For CO2?

A

Bubble the sample through limewater, positive result leads in limewater turning milky white, due to the limewater(calcium hydroxide) reacts with CO2 to form insoluble calcium carbonate.

7
Q

Explain Effects of Physical Activity

A

Exercise leads to cramps, where muscles do not have enough O2 leading to incomplete breakdown which produces lactic acid, so rate of breathing increases to try to keep supply up to meet demand.
Solution to cramp: Stop and breath so lactic acid finishes conversion and pain goes away

8
Q

What is the Larynx?

A

Larynx, or voice box, sits beneath the epiglottis, and underneath splits into trachea and oesophagus, and manipulates pitch and volume, essential for phonation

9
Q

What is the contraction of muscles to move things called?

A

Peristalsis.

10
Q

What is the Epiglottis?

A

A flap which prevents food from going down into the trachea, choking.

11
Q

What keeps the windpipe open?

A

Rings of cartilage.

12
Q

What does tobacco do to your lungs?

A

It breaks the walls between alveoli.

13
Q

Why are the alveoli in grape-like bunches?

A

To increase surface area to maximise efficiency,

14
Q

Describe Inhalation and Exhalation.

A

Inhale/Exhale
Ribcage muscles and diaphragm contract/relax, volume of thorax increases/decreases, pressure in lungs decreases/increases, air enters/leaves lungs.

15
Q

Describe the Alveoli and how they specifically adapt for their purpose.

A

They are moist for dissolving gas, have very thin walls to allow gas to pass through, and cover a large surface area. In them, O2 enters and exchanges with red blood cells in capillaries branching from pulmonaries without O2 for CO2, (purply coloured cells).

16
Q

State differences in composition of inspired and expired air.

A

Air In : Strong triple covalently bonded N2 78%, Oxygen 20%, Carbon Dioxide 0.04%, and 0.93% Argon.
Air Out : Now contains water, 4-5% CO2 and less oxygen.

17
Q

Why is the process of suction of air into lungs a misnomer?

A

The pressure in the lungs is less than the pressure of the atmosphere so the air is forced into the lungs from outside via the nose/mouth.

18
Q

Define Gas Exchange.

A

Physical process in which gas, oxygen is exchanged for carbon dioxide across a membrane surface.

19
Q

What are the major toxic components of tobacco smoke?

A

Tar, nicotine, carbon monoxide, smoke particles.

20
Q

Explain the role of mucus in the gas exchange system.

A

Goblet cells release mucus which evaporates and moistens the nose, and cilia are tiny, hair-like projections which are constantly moving. These trap bacteria and dust particles, so they don’t move further into the gas exchange system.