Chapter 6

Question 0

Why do we need a transport system

Answer 0

We have a decrease in SA ratio therefore, we can no longer rely on simple diffusion and need to develop special exchange surfaces that link to transport systems

Question 1

what does the blood circulatory system consist of?

Answer 1

• blood vessels through which blood is transported

- the heart, a muscular pump that keeps blood moving

Question 2

Components of blood

Answer 2

Plasma, red blood cells, platelets, white blood cells

Question 3

Plasma

Answer 3

Pale yellow fluid, carries blood cells and platelets suspended in it.
Also carries dissolved gases, nutrients, wastes, hormones and proteins.

Question 4

Red blood cells

Answer 4

Carry oxygen to all cells of the body

• contain hemoglobin
• produced in the bone marrow,

Question 5

What is haemoglobin

Answer 5

A red iron containing protein that readily combined with oxygen to form oxy-haemoglobin

Question 6

White blood cells

Answer 6

Protect body from invading microorganism s

• are fewer than RBC
• can be found in tissues as well, squeezing through capillaries to get to damaged cells

Question 7

Platelets

Answer 7

Initiate blood clotting

- formed in bone marrow

Question 8

Arteries

Answer 8

Transport blood from the heart to body

• have thicker walls than veins
• nerves and hormones can cause them to constrict or dilate
• thick elastic layer
• no valves

Question 9

Why do arteries have thicker wall than veins?

Answer 9

Arteries have mor muscle and elastic fibers, to withstand force of heart pumping blood around the body

Question 10

Capillaries

Answer 10

Thin wall, only 1 cell thick

• no valves
• no muscles
• no elastic
• diameter the same as RBC
• has vessels in which dxchange of gases, nutrients and wastes (CO2) occurs

Question 11

What is function of tissue fluid

Answer 11

It is fluid that allows the exchange of substances between blood and cells

Question 12

What is found in tissue fluid?

Answer 12

Glucose, amino acids, fatty acids, salts and oxygen = all delivered to the cells

Question 13

Veins

Answer 13

Transport blood from the body to the heart

• have valves to maintain a one way movement of blood
• thin elastic layer and thin muscle layer

Question 14

How are arteries and veins connected

Answer 14

They are connect by a network of arterioles, very thin walled vessels called capillaries and venules.

Question 15

Features of human heart

Answer 15

Four chambered heart
Double pump ( right side pumps blood to the lungs, left side pumps blood around the body)
Made of cardiac muscles

Question 16

Single circulation of blood

Answer 16

In fish, fish only have two chambered heart
Blood pressure reduced as blood passes through the villa capillaries, slows down flow to the rest of the body. Blood passes through heart ONCE per complete circuit

Question 17

Double circulation

Answer 17

• more efficient for mammals
• heart is composed of two separate pumps.
  Blood passes through heart TWICE per complete circuit

Question 18

Features of closed circulatory system

Answer 18

• blood, fluid that moves around a series of vessels carrying nutrients and oxygen to all parts of body
• a pumping organ, the heart, that forces blood through the system
• vessels, carrying blood to tissues and returning to heart

Question 19

Amphibians and reptiles heart

Answer 19

Mostly have three chambered hearts
Oxygenated and deoxygenated bloods mix in the single ventricle as blood flows through the heart twice for every circulation

Question 20

Open circulatory system

Answer 20

The blood contained in vessels for some of the time, leaves the vessels to bathe tissues, then returns to the vessels.
Insect blood does not transport oxygen. They have a series of air filled tubes or teaches that provide oxygen to living cells.

Question 21

Lymph is moved by

Answer 21

• hydrostatic pressure

- contraction of body muscles

Question 22

Main role of lymphatic system

Answer 22

To collect and transport tissue fluid from the tissues of the body back into the veins in the blood systems.
Has valves to prevent back flow of lymph.

Question 23

What transports nutrients to all living cells

Answer 23

Plasma of blood