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Flashcards in Final Deck (43)
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1
Q

Increases in which of the following components of Fick’s law of diffusion would NOT result in an increase in gas exchange across a respiratory surface?

A

Path length

As the length a compound diffuses increased, the rate of diffusion would decrease.

2
Q

A simple solution to gas exchange in some aquatic animals is to keep the body very thin (shown, a marine flatworm, Pseudodoceros sp.). Which of the statements about water and air (respiratory media) is FALSE?

A

Limits imposed by the slow diffusion of O2 molecules in water are completely avoided in animals that breathe air.

True:
D. A given volume of water holds much less oxygen than the same volume of air.
E. A fish breathes water.
A. Active transport mechanisms are not directly involved in the diffusion gases across membranes.
B. Aquatic organisms expend more energy moving water across their exchange surface than terrestrial organisms.

3
Q

Which component of the human respiratory system would collapse due to surface tension if surfactants were not present in the lungs?

A

Alveoli

A lack of surfactant is associated with respiratory distress syndrome, resulting in an alveolus (the gas exchange surface), which is difficult to inflate (remains collapsed).

4
Q

Which of the following statements about ventilation of human lungs is FALSE?

A

Inhalation depends on positive alveolar pressure; exhalation depends on negative alveolar pressure.

This statement is false; the reverse is true. Contraction of the diaphragm produces a negative pressure within the pleural cavities expanding the lungs and reducing pressure, thereby drawing air in. Relaxation of the diaphragm leads to an increase in pressure within the lungs (positive pressure) that forces the air out.

5
Q

The primary respiratory gas(es) is/are

A

Oxygen and Carbon Dioxide

6
Q

Respiratory gases are exchanged between the body fluids of an animal and its environment by

A

Diffusion

7
Q

Why is air a better respiratory medium than water?

A

A. A given volume of air can contain more O2 than the same volume of water.
B. O2 diffuses faster in air than in water.
C. Less work is required to move air over respiratory exchange surfaces.
D. As water temperature increases, less O2 is available.

8
Q

Breathing in vertebrates other than birds is _______ and is less efficient than gas exchange in fish or birds.

A

tidal

9
Q

In mammalian lungs, the gas exchange surface area provided by _______ is enormous.

A

Alveoli

10
Q

Two molecules of hemoglobin can bind a maximum of _______ molecules of _______.

A

Eight respiratory gas molecules

11
Q

The ability of hemoglobin to pick up or release O2 depends on

A

the PO2 of its environment.

12
Q

When is the ventricular blood volume higher?

A

At the beginning of systole

13
Q

In the cardiac cycle, when do the atrioventricular valves close?

A

During systole

14
Q

The three principle functions of the vertebrate circulatory system are:

A

Transport, protection, and body temperature regulation

15
Q

When blood leaves the right ventricle of the mammalian heart, to which location does it flow next?

A

The kungs

16
Q

With each heartbeat, the muscle cells coordinate themselves so that each contraction is forceful enough to circulate blood through the entire body. The beat begins in the _____________node, which sets the tempo of each beat, thus giving it the name of pacemaker.

A

Sinoatrial

17
Q

How are the blood-circulation system and the lymphatic system related to each other?

A

Blood carries nutrients and oxygen to cells and removes their waste. The lymphatic system removes bacteria and debris from the blood.

18
Q

Both birds and mammals have four-chambered hearts. But birds are more closely related to crocodiles, which have three-chambered hearts, than they are to mammals. The correct interpretation of these observations is that:

A

a) birds and mammals evolved four-chambered hearts independently.
b) birds and mammals both have higher energy requirements than crocodiles.

19
Q

Which of the following is the name of the fluid in an insect’s open circulatory system?

A

hemolymph

20
Q

The volume of blood that is composed of blood cells is referred to as the:

A

hematocrit

21
Q

The lymphatic system is a fluid transport system vital for human health. Instead of blood, this system transports _________, which fills its own capillaries and vessels and is made up of the _________________ fluid that bathes cells.

A

lymph; interstitial

22
Q

Which of the following is NOT a function of the blood plasma in vertebrates?

A

transporting oxygen throughout the body

23
Q

Organisms with an open circulatory system:

A

pump fluid throughout the spaces of their body cavity where it mixes with tissue fluids.

24
Q

In a person at rest, most of their blood is likely to be in the:

A

Veins

25
Q

Which feature of insects makes it necessary for them to use active transport to filter extracellular fluids into the Malpighian tubules?

A

open circulatory system

26
Q

An air environment, gravity, and desiccation are three challenges that were addressed in the evolution of reptiles.

What three evolutionary innovations addressed these challenges?

A

lungs, better limb support, and the amniotic egg

27
Q

In the sense that it regulates water and electrolyte balance, the shark’s rectal gland is similar to the _____________ of terrestrial vertebrates.

A

Kidneys

28
Q

Animals must eliminate the end products of metabolism. The metabolism of which of the following can prove toxic and as such is the major reason waste must be excreted?

A

Proteins and Nucleic Acid

29
Q

The thick ascending limb of Henle actively transports NaCl into the interstial fluid and is impermeable to water. How does this effect the filtrate entering the thick ascending limb?

A

The higher osmolarity of the interstial fluid causes osmotic reabsorption of water from the descending limb, concentrating the tubule fluid entering the ascending limb.

30
Q

Which of the following is true about the brain of a person with Alzheimer’s disease?

A

Alzheimer sufferers have significantly reduced brain activity in thinking and understanding.

31
Q

MDMA (3,4-methylenedioxy-N-methylamphetamine), commonly known as ecstasy has what effect on human neurons?

A

It increases the release of serotonin.

It inhibits the re-uptake of serotonin

32
Q

The autonomic nervous system consists of _____________ pathways that control the physiological function of organs and organ systems.

A

efferent

33
Q

The blood-brain barrier:

A

is formed from muscle tissue.

prevents harmful molecules such as metabolic wastes from passing into the brain.

34
Q

The disease multiple sclerosis (MS) is caused by:

A

progressive damage to the myelin insulating neurons, reducing their ability to conduct electrical signals.

35
Q

What is the function of glial cells?

A

Assist and nourish neurons

36
Q

Interneurons are located where?

A

Confined to the spinal cord and brain.

37
Q

Which part of the limbic system is responsible for the transfer of short-term memory to long-term memory?

A

Hippocampus

38
Q

Brain tumors (like most tumors) are generally the result of unstoppable cell division. Yet in adult humans, most neurons in the brain do not divide at all. How can these two facts be reconciled?

A

Brain tumors are usually formed from glial cells, the supporting cells of the brain, which divide regularly.

39
Q

O2 enters the cell by

A

Simple diffusion

39
Q

What are the two primary means by which communication between parts of a multi-cellular animal is accomplished?

A

neural and hormonal

40
Q

From air to red blood cell, O2 passes through

A

5 membranes

41
Q

1L air holds ~200 mL O2

A

1L water holds ~10 mL

42
Q

CO2 would have greater Q than O2 because

A

P1-P2 is larger