Gas Exchange 🪲🐻🫁

Question 1

Surface area to volume ratio…

Answer 1

Decreases as an organism gets larger

Question 2

Oxygen is required to produce ___ during aerobic respiration

Answer 2

ATP

Question 3

Carbon Dioxide is produced as a waste product during aerobic respiration. What does that do?

Answer 3

Generates a concentration gradient of CO2 and O2 in opposite directions

Question 4

Why do single celled organisms not need gas exchange systems?

Answer 4

they have a large SA:V ratio to meet their gas exchange needs by diffusion across their cell membranes.

Question 5

Why do larger organisms need gas exchange systems?

Answer 5

They have a relatively small (in comparison to single celled organisms) SA:V ratio and they can not rely on diffusion alone to meet the oxygen demands to all of their cells

Question 6

What is Fick’s Law:

Answer 6

Rate of Diffusion=

SA x Conc gradient
—————————-
Diffusion pathway

Question 7

Insects need gas exchange what else do they need?

Answer 7

the need to conserve water

Question 8

What is the most effective surface for gas exchange? And what else are these features favourable for?

Answer 8

Most effective surface: large, thin and permeable area
They are also favourable for evaporation leading to potentially fatal dehydration

Question 9

To limit water loss, what adaptations to insects have?

Answer 9

Waterproof covering over their body surfaces. Rigid exoskeleton covered with waterproof cuticles.

Relatively small SA:V to minimise the area over which water is lost

Question 10

The order of gas exchange in insects

Answer 10

Spiracles , tracheae, tracheoles, respiring tissue

Question 11

What is the primary function of spiracles in insects?

Answer 11

Oxygen enters the insect through spiracles and into the tracheae

Spiracles are small openings that allow gas exchange.

Question 12

What are tracheae?

Answer 12

The tubes that transport oxygen from spiracles to tracheoles

Tracheae are part of the insect respiratory system.

Question 13

What are tracheoles?

Answer 13

The smallest branches of the tracheal system that deliver oxygen directly to tissues

Tracheoles are crucial for efficient gas exchange.

Question 14

What happens when spiracles close?

Answer 14

Oxygen diffusion through the tracheae into the tracheoles occurs

This process is driven by concentration gradients.

Question 15

Describe the movement of oxygen through the insect.

Answer 15

1. Oxygen enters through spiracles
2. Moves into tracheae
3. Diffuses into tracheoles
4. Delivered to respiring tissues

This process is essential for cellular respiration.

Question 16

True or False: Carbon dioxide produced by respiring tissues exits the insect when spiracles are closed.

Answer 16

False

Carbon dioxide exits when spiracles are open.

Question 17

Fill in the blank: Oxygen diffuses through the tracheae into the _______.

Answer 17

[tracheoles]

Question 18

What is the role of air sacs in the insect respiratory system?

Answer 18

Air sacs help in the storage and movement of air within the tracheal system

They enhance the efficiency of respiration.

Question 19

How does carbon dioxide move in relation to oxygen in the insect respiratory system?

Answer 19

Carbon dioxide moves in the opposite direction to oxygen

It exits the insect when spiracles are open.

Question 20

What is the significance of concentration gradients in the insect respiratory system?

Answer 20

They drive the diffusion of oxygen into tracheoles

Concentration gradients facilitate gas exchange.

Question 21

List the components involved in the insect respiratory system.

Answer 21

• Spiracles
• Tracheae
• Tracheoles
• Air sacs

These components work together for efficient gas exchange.

Question 22

What are spiracles?

Answer 22

Tiny pores through which gas enters and exits the insect

They are opened and closed to control water loss by evaporation.

Question 23

When do spiracles open?

Answer 23

When CO2 levels increase

This helps in regulating gas exchange.

Question 24

What is the significance of the distance between insect cells and tracheae?

Answer 24

Every cell of an insect is only a very short distance from one of the tracheae or tracheoles

This ensures that the diffusion pathway is always short.

Question 25

What are tracheoles?

Answer 25

Small tubes with thin walls that extend throughout the body tissues They reduce diffusion distance and are highly branched to increase surface area.

Question 26

What is the function of tracheae?

Answer 26

A network of tubes supported by strengthened rings Provides tubes full of air for fast diffusion.

Question 27

Why does diffusion occur in the gas exchange systems of insects?

Answer 27

Oxygen diffuses from areas of higher concentration to areas of lower concentration This is necessary for respiration as tissues consume oxygen.

Question 28

What happens to oxygen concentration in the tissue during respiration?

Answer 28

It reduces as tissues respire using oxygen This creates a concentration gradient that facilitates diffusion.

Question 29

How does oxygen move from the tracheae to the tissue?

Answer 29

Moves from an area of higher concentration in the tracheae to lower concentration in the tissue This process is driven by diffusion.

Question 30

What is the process for carbon dioxide movement in insects?

Answer 30

CO2 moves from high concentration at the tissue to low concentration in the tracheae It then exits the insect through the spiracles.

Question 31

What increases the concentration of carbon dioxide at the tissue?

Answer 31

Respiration produces CO2 This leads to a gradient that drives diffusion out of the insect.

Question 32

What is the primary mechanism of ventilation in insects?

Answer 32

Movement of the insect's muscles creates a mass movement of air in and out of the trachea

Question 33

How do insects increase the rate of gaseous exchange?

Answer 33

By using abdominal pumping and having small air sacs in their trachea Muscles around the trachea contract to pump air deeper into the tracheoles.

Question 34

What happens to water in the tracheoles during rest?

Answer 34

Water can build up in the tracheoles This occurs when the insect is not in flight.

Question 35

What type of respiration may occur during flight in insects?

Answer 35

Anaerobic respiration This can lead to the production of lactate (lactic acid).

Question 36

What effect does lactate accumulation have on muscle cells?

Answer 36

It lowers the water potential of the muscle cells This causes water to pass from the tracheoles into the muscle cells via osmosis.

Question 37

What adaptation helps draw air into the tracheoles during flight?

Answer 37

The accumulation of lactate in muscle cells This reduces the diffusion distance for oxygen when needed.

Question 38

Fill in the blank: During flight, water is drawn into the _______.

Answer 38

muscle cell

Question 39

What occurs at the narrow ends of the tracheoles when an insect is at rest?

Answer 39

Water fills the narrow ends of the tracheoles This is a key feature of the insect's respiratory system.