Respiration (Test Three)

Question 1

Why do fish use up to 20% of their metabolism extracting oxygen from water?

Answer 1

Because water is much more dense and much more viscous than air, so it takes much energy to move.

Question 2

What are outgrowths of the body wall called?

Answer 2

Gills for aquatic respiration, evaginations.

Question 3

What are ingrowths of the body wall called?

Answer 3

Invaginations or trachea / lungs

Question 4

What organisms that we talked about are able to use direct diffusion of gases?

Answer 4

1. Protozoans
2. Sponges
3. Cnidarians
4. Flatworms

Question 5

Describe how insects and other land arthropods exchange gases.

Answer 5

Air enters the spiracles (valve-like) and reaches the trachea, which narrow to tracheoles.

Question 6

Is the respiratory (tracheal) system of insects/arthropods independent of the circulatory system or not?

Answer 6

It is independent.

Question 7

What are two unique examples of gills as simple external extensions?

Answer 7

1. Dermal branchiae of sea stars
2. Parapodia of sand worms
3. Branchial tufts of marine worms

Question 8

How do gills maximize extraction of oxygen?

Answer 8

The blood flow is opposite to the flow of the water so that high concentration O2 in water meets the low concentration of O2 in blood.

Question 9

Briefly describe the action that allows many fish and most sharks ventilate their gills.

Answer 9

They use ram ventilation and buccal pumping which is when water is drawn in through the mouth and passes over the gills through the action of skeletal muscle pumps.

Question 10

Are gills and lungs derived traits?

Answer 10

No evolution solved multiple problems, in this case differently.

Question 11

Why are amphibians unique in their method of gas exchange?

Answer 11

They have decreased lungs but still the ability to breath through them or the unique ability to use direct diffusion, which is why the lungs never fully developed.

Question 12

Describe how frogs are bring air into their lungs.

Answer 12

They use buccal pumping by forcing air into the buccal cavity by gulping air.

Then once air is inside the glottis is opened and air flows into the lungs.

Question 13

What makes non avian reptile’s lungs special?

Answer 13

Their lungs are further subdivided into more air sacs which allow them to always have fresh air available both when inhaling and exhaling.

Question 14

Where is the only place where gas exchange takes place in mammals?

Answer 14

In the alveoli

Question 15

Where is air/food sorted in mammals?

Answer 15

In the pharynx

Question 16

What is the first part of the lung system in mammals?

Answer 16

the trachea

Question 17

What is the purpose of air passageways being lined with mucus secreting and ciliated epithelial cells?

Answer 17

They make sure new air is filtered, warmed, and moistened.

This in turn keeps the alveoli from being harmed, or from drying out

Question 18

Describe the purpose of the diaphragm in the mammalian respiratory system.

Answer 18

When the diaphragm contracts, the volume of the cavity increases which decreases the pressure.

Because pressure is now decreased, air enters to counteract that