Lecture #20 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is diffusion?

A

Random (Brownian) movement caused by thermal energy

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

When is diffusion fast or slow?

A

Slow in long distances; Fast in short distances

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

What determines where the molecules go through diffusion?

A

High concentration to Low concentration

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

When does diffusion across a membrane work best; and when does it not work well?

A

When the membrane of a cell can be completely surrounded by the ion/molecule trying to diffuse; does not work well with thick walls of cells (tissue) because fewer cells can interact with environment

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

What does circulation do and why is it effective?

A

Circulation speeds up transport of ions and molecules. Essentially, it just moves things around the body.

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

What do animals have when they don’t have circulatory systems?

A

Gastrovascular cavities

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

What are gastrovascular cavities?

A

They are open areas (cavities) that place many cells in contact with the environment.

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

Where are gastrovascular cavities present/not present?

A

They are present when animals do not have circulatory systems

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

What kind of tissue do creatures with gastrovascular tissues have and why?

A

Thin creatures since tissues are thin enough to allow sufficient diffusion to all cells

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

Describe how capillaries work in circulatory systems? What purpose do they serve?

A

Capillaries are the part of the circulatory system that transports blood to every cell. This blood contains all the ions, molecules, and nutrients that every cell in our body needs to survive. Ions and small molecules within the blood diffuse across blood vessel cell membranes into skeletal muscle. Red blood cells move single file fashion through capillaries.

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

What are the two types of circulatory systems?

A

Open and Closed

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

What are the 2 main characteristics of an open circulatory system?

A

Vessels don’t form complete circuit ; Blood is called hemolymph since it mixes with interstitial fluid in the body

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

What is the main characteristic of closed circulatory systems?

A

Blood is enclosed in vessels meaning blood never exits vessels

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

What is the water vascular systems and what is its main characteristic?

A

Water vascular system is a circulatory system using sea water instead of blood or hemolymph. Main characteristic: uses hydraulic system for pretty much everything, even moving itself.

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

How do most pathogens enter the body and why?

A

They enter through the circulatory system (blood) since it has access to essentially every cell in the body that way (do the most damage)

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

What are the 6 things that circulatory systems move (excluding pathogens)?

A

Oxygen, sugars, hormones, antibodies, carbon dioxide, and urea

17
Q

What is blood made of?

A

Is a tissue made of cells, platelets, and plasma

18
Q

What are the two types of cells in blood?

A

Erythrocytes and leukocytes

19
Q

What are erythrocytes and how do they work?

A

They are red blood cells that transport oxygen. They are packed with hemoglobin, a protein that binds to 4 oxygen each and can release oxygen molecules when in an environment with little oxygen

20
Q

How are red blood cells shaped and why?

A

They have a concave shape that gives them high SA/V ratio.

21
Q

What are leukocytes and how do they work?

A

They are white blood cells (immune cells) that defend against pathogens. They also have weirdly shaped nuclei whereas red blood cells have no nuclei.

22
Q

Why do red blood cells not live that long?

A

They have no nuclei (90-100 days lifespan)

23
Q

What are platelets and what is their function?

A

They are tiny fragments of red blood cells that form clots to aid in injury. hormone is sent out that attracts platelets.

24
Q

What is plasma and what is its purpose?

A

Plasma is a fluid within blood that is 95 percent water and carries everything that blood is transporting (except for oxygen) including ions, glucose, hormones, and proteins.

25
Q

How is blood transported?

A

Blood is transported in vessels.

26
Q

What are arteries? What are its 2 characteristics?

A

Vessels that take blood away from the heart. They have thin diameter to speed up blood movement and covered in thick layer of smooth muscle to open and close the arteries.

27
Q

What are veins? What are their two characteristics?

A

Veins bring blood towards the heart. They have big radius meaning low pressure. They also have valves that prevent back flow of blood when it stops moving between heart pumps

28
Q

What are capillaries?

A

The site of gas/solute exchange. Where the work of the circulatory systems happen. They are one blood cell thick, so the net movement is very fast.

29
Q

What are the three types of hearts that an organism can have?

A

Two chambered, three-chambered, and 4 chambered

30
Q

What type of circulation (circulatory system) does each type of heart have?

A

2-chambered- single circulation ; 3-chambered and 4-chambered-double circulation

31
Q

Describe single circulation in a 2 chambered animal?

A

One circuit; blood goes straight from lungs into rest of the body, does not stop at the heart to spread blood quickly throughout the body.

32
Q

Describe double circulation in a 3 chambered animal?

A

2 circuits; one dedicated to respiratory functions (bringing blood to lungs for oxygen/deoxygenate, and one for body/systematic functions (transporting O2 and nutrients to cells). Blood goes from heart to lungs, back to heart, and to the rest of the body.

33
Q

Describe double circulation in a 4 chambered animal

A

4 chambered animal has 2 ventricles, meaning complete separation of the two circuits and efficient movement of the blood. Also, blood going from lungs back into heart means blood can move quickly throughout the body.

34
Q

What is the main difference between three chambered and four chambered hearts?

A

4 chambered has two ventricles, 3 chambered only has one. This means, in 3 chambered hearts, one ventricle is pumping some blood to body and some blood to lungs, meaning some blood doesn’t get oxygenated before getting back into body.

35
Q

What is unique about the evolution of 4 chambered hearts?

A

They evolved twice, in mammals and archosaurs