Circulation (Test Three)

Question 1

Why can sole diffusion only be used in very small, single-celled organisms as means of transporting nutrients, wastes and gases in and out of cells?

Answer 1

Because exchanging materials becomes very inefficient, and only cells less than 1mm in diameter are able to do it efficiently.

Question 2

Describe the two types of body fluid.

Answer 2

1. Intracellular fluid - sum of all fluids inside cells
2. Extracellular fluid is the fluid that resides outside cells surrounding them, and provides a buffer for physical and chemical change

Question 3

What is extracellular fluid further divided into?

Answer 3

1. Blood plasma - contained in the blood vessels
2. Interstitial fluid - lies between cells in tissues

Question 4

How is interstitial fluid formed?

Answer 4

It is formed from blood plasma moving into and out of tiny blood vessels called capillaries

Question 5

All the components of body fluid differ in what way and are mainly made of what?

Answer 5

They differ in their solute concentration and they are composed of mainly water

Question 6

What is blood called for invertebrates with open circulatory systems?

Answer 6

Hemolymph (blood-fluid)

Question 7

Invertebrates with closed circulatory systems are able to keep what two thing separate?

Answer 7

The blood in the blood vessels and the interstitial fluid surrounding the cells

Question 8

Describe the fluid portion of vertebrate blood.

Answer 8

1. (Plasma) takes up 55% of blood
2. 90% water
3. Contains solids like plasma proteins, sugar, antibodies, and hormones
4. Also contains dissolved gases like O2 CO2 and N2

Question 9

Describe the cellular part of vertebrate blood.

Answer 9

1. Makes up 45% of blood
2. Contains RBC’s, WBC’s and Cell fragments (platelets aka thrombocytes)

Question 10

Describe the three main plasma proteins.

Answer 10

1. Albumins - (60%) keep plasma in osmotic equilibrium
2. Globulins - (35%) function by acquiring immunity
3. Fibrinogen - (5%) function in part to blood clotting

Question 11

What is plasma called without the proteins?

Answer 11

Serum

Question 12

Describe general RBC’s in more detail including their formal name.

Answer 12

1. Called Erythrocytes, enormous numbers in blood
2. Lack nucleus (for more surface area)

Question 13

How are RBC’s made in birds and mammals

Answer 13

produced in the bone marrow

Question 14

How are RBC’s made in other vertebrates?

Answer 14

in the kidney and spleen

Question 15

What happens when RBC’s die in a human being?

Answer 15

They are removed by macrophages in the liver and the iron is salvaged and recycled, and the heme (broken down hemoglobin) is converted to bilirubin

Question 16

Describe the first line of defense in hemostasis (blood clotting)

Answer 16

When a blood vessel is damaged, smooth muscle lining the vessel contracts

Question 17

The special components to clotting are present in which types of organisms?

Answer 17

1. in vertebrates
2. Larger active invertebrates

Question 18

Where do platelets come from?

Answer 18

They form in the bone marrow from fragments of large multi-nucleated bone marrow cells.

Question 19

What do platelets do?

Answer 19

They adhere to any disruption in the inner surface of the blood vessel.

Question 20

Walk through the specific cascade how blood clotting happens.

Answer 20

When an injury occurs, the platelets adhere to the blood vessel and release blood clotting factors, which with the help of calcium and existing platelet factors allow prothrombin which is contained in the plasma to be converted into its active form thrombin. Once the active thrombin is available, it allows the plasma protein fibrinogen we talked about to form fibrin which will act like a web sealing the area.

Question 21

What does a complete circulatory system involve?

Answer 21

1. Propulsive organ
2. Arteries
3. Capillaries
4. Venous reservoir
5. Return system

Question 22

Describe the circulatory system in fish.

Answer 22

They have a two chambered heart that pumps blood from the heart to the gills to become oxygenated, on its way to the body.

Flows one directionally

Question 23

Describe circulation in amphibians.

Answer 23

1. They have a three chambered heart with two atria and one ventricle
2. One atria takes blood to the lungs where gas is exchanged and then returned to the other atria and ventricle where it is mixed and pumped to systematic vascular beds or back to the lung.
3. This mixing reduces the efficiency of oxygenation
4. Important to recognize that blood exiting the ventricle is diverted, some back to the lung and some to the vascular beds, illustrating the inefficiency.

Question 24

Describe bird and mammal circulation

Answer 24

1. Four chambered heart
2. Complete separation of both systematic and pulmonary circuits (oxygenated blood and deoxygenated blood)