Chapter 8 Keywords

Question 1

Mass transport system

Answer 1

Substances are transported in a mass of fluid with a mechanism for moving the fluid around the body

Question 2

haemolymph

Answer 2

Insect blood. It doesn’t carry oxygen or CO2 (those are exchanged in the tracheal system)Just transports food and nitrogenous waste and cells involved in defence against disease

Question 3

Haemocoel

Answer 3

Open body cavity of insects. Split by a membrane and the heart extends the length of the thorax and abdomen of the insect.

Question 4

Elastic fibres

Answer 4

Compounds of elastin, a fibrous protein.
Can stretch and recoil
Providing vessel wall with flexibility

Question 5

Smooth muscle

Answer 5

Contracts or relaxes

which changes the size of the lumen

Question 6

Collagen

Answer 6

Provides structural support to maintain shape and volume of the vessel

Question 7

Vasoconstriction

Answer 7

-smooth muscle contracts, vessel constricted and blood prevented from flowing into a capillary bed

Question 8

Vasodilation

Answer 8

-smooth muscle of the arterioles relax, vessel dilated and blood flows through the capillary bed

Question 9

Capillaries

Answer 9

Microscopic blood vessels that link the arterioles and the venules. RBC travel through them in single file

Question 10

Platelets

Answer 10

55% is plasma. Most of Which is water
Fragments of large megakaryocytes founds in the red bone marrow.
Involved in blood clotting

Question 11

Leucocytes

Answer 11

Wbcs

Many diff types with many diff functions

Question 12

Plasma

Answer 12

Yellow liquid
carries dissolved glucose and a.a mineral ions, hormones ,rbcs, wbcs and large plasma proteins
-albumin
Important for maintaining osmotic pressure of the blood
-fibrinogens
Important for blood clotting
-globulins
Involved in transport and the immune system

All of these can pass thru cap walls except the large plasma proteins

Question 13

Plasma proteins

Answer 13

Albumin
Fibrinogen
Globulins
Esp albumin have osmotic effect. Lower wp of the blood in the Capps so water moves in from surrounding fluid by osmosis.

Osmotic pressure is about -3.3kPa

Question 14

Osmotic pressure

Answer 14

The tendency of water to move into the blood by osmosis

Question 15

Hydrostatic pressure

Answer 15

As blood flows through the arterioles into the Capps it’s still under pressure from the surge of blood that occurs every time the heart contracts

Question 16

Tissue fluid

Answer 16

Same composition as plasma but without the rbc and plasma proteins
Diffusion takes places between blood and cells through tissue fluid. 90% of the tissue fluid returns to Capps

Question 17

Lymph

Answer 17

The 10% of tissue fluid that doesn’t return to the Capps. It drains into a system of blind ended tubes called lymph Capps. Similar composition to plasma and tissue fluid but with less O2 and fewer nutrients

• contains fatty acids that have been absorbed into the lymph from the villi of the small intestine
• lymph Capps join up to form larger vessels
• fluid is transported through them squeezing of the body muscles
• one way valves to prevent backflow of lymph
• eventually lymph returns to blood flowing into the right and left subclavian veins

Question 18

Lymph nodes

Answer 18

• Found Along the lymph vessels.
• intercepts bacteria and other debris from the lymph
• ingested by phagocytes found in the nodes.

Lymphocytes build up in the lymph nodes when ness and make antibodies that are then passed into the blood.

Question 19

Diastole

Answer 19

Heart relaxes
Atria and then ventricles fill with blood.
Vol and pressure increase as heart fills
Pressure in the arteries is at a minimum

Question 20

Systole

Answer 20

Atria contract, then ventricle contract,
Drastic Pressure increase
Blood forced out of the right side to the lungs
Blood forced out of left side to the body

At the end vol and pressure low. In arteries pressure at the max

Question 21

What are the heart sounds

Answer 21

First one
Blood forced against the AVV as ventricles contract

Second one
Backflow of blood closes the semilunar value in the aorta and pulmonary artery

Question 22

What happens in atrial fibrillation

Answer 22

An example of an arrhythmia
Electrical impulses are generated in the atria
They contract very fast, but to 400times a minute.
Don’t contract properly tho and only some impulses passed onto the ventricles that contract much less often so heart nah pump very effectively

Question 23

How does an ECG work

Answer 23

Electrodes are stuck painlessly to clean skin to get good contact needed for realiable results
Signals from each of the electrodes is fed into the machine which makes an ECG

Question 24

Uses of the ECG

Answer 24

To measure the spread of electrical excitation through the heart. Measuring the tiny electrical differences in ur skin

Used to diagnose heart problems
Recognisable changes in the electrical activity of someone’s heart can tell you if they’re having a heart attack for example. From there you can diagnose and treat correctly and fast

Question 25

Myogenic

Answer 25

Heart has its own intrinsic rhythm so bodies resources nah wasted maintaining heart rate at a basic level

Question 26

Bundle of His

Answer 26

A bundle of conducting tissue that is made up of Purkyne fibres that penetrate thru the septum between the ventricles