Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BISC 101 > Final Exam > Flashcards

Final Exam Flashcards

1
Q

Why do mice have a higher basal metabolic rate compared to elephants?

A

The mouse has more surface area to take in oxygen and get rid of waste quickly for the amount of volume inside. The elephant does not have a large surface area, so it does it slower.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Can salmon breathe through skin and gills? Which predominates?

A

Young salmon breath mostly through skin and the older ones through gills because of surface to volume ratio.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is homeostasis and why is it important?

A

The ability to maintain a constant internal environment in response to environmental changes. It is important because it allows to operate almost optimal conditions under changing conditions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is required for homeostasis to take place?

A

-Sensor: detects status of internal or external environment
-Integrator: evaluates sensor information and decides if action is needed
-Effector: mechanism that helps restore desired condition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Explain endothermic and ectotherm:

A

-Endothermic: producing heat inside using metabolic pathways
-Ectotherm: gains heat from outside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Explain homeotherms and poikilotherms:

A

-Homeotherms: keep their body temperature constant
-Poikilotherms: allow their body temperature to change depending on environmental conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Explain Freeze avoidance vs. Freeze tolerance:

A

-Freeze avoidance: keeps body fluids liquid below 0 degrees C
-Freeze tolerance: keep ice formation outside of cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Explain Countercurrent vs. Concurrent

A

-Countercurrent: small gradients are maintained and constant
-Concurrent: large gradients don’t stay for too long and disappear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is an osmoconformer?

A

Organisms that maintain the same osmolarity as surroundings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are osmoregulators?

A

Organisms that maintain a different osmolarity than the surroundings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What happens if the fish moves to freshwater?

A

Freshwater fish have to take in salt as there is no salt in the surrounding. Na+/Cl-/K+ contransporter is in opposite direction (in the apical membrane) so that the salts come inside the fish.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How can locusts prevent water loss?

A

-The cuticle is very hydrophobic and does not allow water to go through
-The spiracles (through which air comes from) can be closed to prevent water loss
-Water and minerals can be reabsorbed by releasing filtrate into hindgut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How is electrolyte balance maintained? What drives the movement of ions across membrane?

A

Ions are moved either by active transport or passive transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How is water balance maintained? What drives the movement of water across membranes?

A

Water movement is driven by osmosis. Water movement is facilitated through some proteins that make the membrane more permeable for water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How is nitrogenous waste eliminated?

A

Removal strategy depends on water availability.
-Ammonia: easy to make, but is toxic and requires lots of water
-Uric acid: most energy consuming synthesis; minimal water
-Urea: some energy required; water soluble but harmless; contributes to osmolarity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a nephron?

A

Tubular system in the kidneys that starts in the cortex and ends in the medulla. They filter blood, remove waste, and re-absorb ions, nutrients and water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Name the pathway of the nephron:

A
  1. Renal corpuscle
  2. Proximal tube
  3. Loop of Henle
  4. Distal tube
  5. Collecting Duct
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the precursor for Vitamin D?

A

Cholesterol. Sunlight can break down cholesterol to make vitamin D; an enzyme is not needed for this step.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the four phases of the digestive system?

A

-Ingestion: taking food into digestive tract
-Digestion: breakdown into smaller pieces
-Absorption: uptake of nutrients
-Elimination: disposal of waste

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Difference between incomplete digestive tract and complete digestive tract:

A

-Incomplete: food goes in from the same way waste comes out
-Complete: food goes in from the mouth and comes out from the anus (aka the alimentary canal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What systems are a part of the digestive system?

A

-Primary (do the job): mouth, esophagus, stomach, small intestine, large intestine, and anus
-Secondary (aid the job): salivary glands, liver, gall bladder, pancreas

22
Q

What is peristalsis?

A

Wave of contraction with food through the esophagus

23
Q

What seals off the stomach in 2 places?

A

Sphincter seals off stomach from esophagus and from small intestine

24
Q

How are lipids broken down since they are hydrophobic?

A

Bile slats made in the liver bind to the lipids and it blends lipids which results into them breaking into monoglycerides and fatty acids

25
Q

What causes diarrhea?

A

When the water reabsorption is disrupted, not enough water is absorbed back into the system; instead, it gets flushed out with feces and results into diarrhea.

26
Q

What happens in organisms that have no circulatory system?

A

There is only diffusion, water goes inside the organism and comes out the organism in a simple mechanism.

27
Q

What is an open circulatory system?

A

The hemolymph (the blood) pumped by the heart is not restricted to vessels or arteries, it bathes in tissues and organs openly.

28
Q

What is a closed circulatory system?

A

When the heart pumps blood through tubular vessels. The vessels branch out into capillaries where gas exchange happens.

29
Q

Arteries vs. Veins:

A

-Arteries: carry blood from the heart
-Veins: return blood to the heart

30
Q

What are the two chambers in the heart?

A

-Atrium: blood enters heart in the atrium
-ventricle: blood leaves from the ventricle and oxygen in taken up

31
Q

Explain the blood flow system step by stem:

A

The blood enters from the vena cava to the right atrium. From the right atrium to the right ventricle. From the right ventricle to the pulmonary artery. From the pulmonary artery to the lungs. From the lungs to the left atrium. From the left atrium to the left ventricle. From the left ventricle to the aorta. From the aorta throughout the body. From throughout the body back to the vena cava.

32
Q

What are pacemaker cells?

A

They send signals to muscles of ventricles to contract in rhythmic way

33
Q

What is the step by step process of the pacemaker cells?

A
  1. The signals originate at SA node
  2. Signal spreads over atria
  3. Signal is delayed at AV node
  4. Signal spreads along conducting fibres to bottom and then top of ventricles; ventricle contract
  5. Ventricles relax
34
Q

Diastole vs. Systole:

A

-Diastole: the pressure of the blood flow when its at rest
-Systole: the pressure of the blood flow when the heart beats

35
Q

What does the rate of diffusion depend on?

A

-concentration difference
-distance
-surface area of barrier

36
Q

What is Fick’s Law:

A

Rate of diffusion=kxAx((P2-P1)/D)

37
Q

What is cooperative binding?

A

Binding of O2 to one subunit changes the affinity of the other subunits

38
Q

How does communication work electrically?

A

In the nervous system, neurons give electric signals.

39
Q

What are the parts of a neuron?

A

-axon: tail
-dendrites: the little hairs that receive a signal from other neurons and transfers signals towards the rest of the neuron

40
Q

What are the connections between neurons (axon - dentrite) called?

A

Synapses

41
Q

What is a membrane potential

A

It’s when there is an electrical gradient of more Na+ outside the cell than the K- charge inside which creates a negative charge. The resting membrane potential is -65 mV.

42
Q

What leak channels are there in the membrane potentials?

A

-K+ leak channels: when K+’s negative charge is attracted by the Na+
-Na+ leak channels: the Na+ goes to the more negative side and the side that was more negative becomes more positively charged than it was before. From -65 mV, it becomes +40 mV.

43
Q

What are the terms used when the membrane potential’s original polarity of the membrane changes and when the channel is closed again?

A

-Original polarity of the membrane disappears: membrane is depolarized
-If the channel is closed again: membrane will be repolarized

44
Q

If the neuron signalling started from the middle of the axon, what would happen to the action potential?

A

The direction of the Na+ would go in both directions since hyperpolarization would not occur

45
Q

What is hyper polarization and what does it do?

A

Hyperpolarization is a phase of the action potential where the membrane potential becomes more negative than the -65mV line so that the nerve signals flow in one direction

46
Q

What is the axon covered with?

A

The axon is surrounded by sheets of myelin called the Schwann cell which produces the layers. This does not allow leakage of electricity outside and acts as an insulation.

47
Q

What are the nodes in the axon called? What do the nodes contain?

A

They are called nodes of Ranvier. The nodes contain Na+/K+ ion channels

48
Q

What are presynaptic and postsynaptic?

A

Presynaptic: the connected axon
Postsynaptic: the connected dendrite

49
Q

What is the space between the presynaptic and postsynaptic neuron called?

A

Synaptic cleft

50
Q

What are the different types of chemical signals?

A

Autocrine, paracrine, endocrine, neural, neuroendocrine signals

BISC 101 (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions