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Flashcards in Blood Deck (16):
1

Name the 3 groups of cells found in the blood

Erythrocytes, leukocytes and thrombocytes ( platelets).

2

Name 5 white blood cells present in the blood, and state the main function of each

Neutrophils- phagocytise bacteria
Eosinophils- kill parasitic worms
Basophils- release histamine, heparin anticoagulant
Lymphocytes- amount immune response- direct cell attack or antibodies
Monocytes- develop into macrophages

3

What is the sequence of events that prevents the loss of blood from blood vessels?

Haemostasis

4

What is the most abundant plasma protein?

Albumin

5

What are the 3 stages of Haemostasis?

1. Vascular spasms- vessel/capillaries constrict, vasoconstriction
2. Platelet plug formation- platelets adhere, release chemicals that make other platelets sticky, plug forms.
3. Fibrin forms a mesh- traps RBCs and platelets, forming clot.

6

What is the fluid portion of the blood?

Plasma

7

What is the red pigment in blood and what is it's function?

Haemoglobin.
It's function is to bind iron and oxygen in blood.

8

What is the lifespan of erythrocytes?

120 days

9

What does the intrinsic conduction system consist of?

Cardiac cells that initiate and distribute a wave of electricity throughout the heart.

10

Where and how is iron stored in the body?

Liver, also in haemoglobin and ferritin-proteins in liver.

11

What is a characteristic of anaemia?

A lack of intrinsic factor, which leads to a deficiency in vitamin B12 and formation of large pale cells called macrocytes.

12

How many litres of blood due most adults have?

5-6 litres

13

Define the terms End Diastolic Volume and End Systolic Volume?

EDV= the amount of blood that collects in a ventricle during diastole.

ESV= the volume of blood remaining in a ventricle after it has contracted.

14

Define cardiac output?

Amount of blood pumped by each side of the heart in 1 minute.

15

Define stroke volume?

Volume of blood pumped by each ventricle in one contraction.

16

List and discuss the short term and long term mechanisms that regulate BP

SHORT TERM
Baroreceptors- sensory receptors that are sensitive to stretch. Detect small changes in BP. Depending on cause bradycardia/tachycardia

Adrenal Medullary Mech.- activated by substantial increase in sympathetic stimulation of heart & blood vessels; epinephrine-vasoconstriction; norepinephrine- vasodilation

Chemoreceptors- help maintains homeostasis when O2 decreases or CO2 & hydrogen increase. Hyperventilation.

CNS ischemic response- only activated in emergency/rare conditions. Acidosis? Increase peripheral resistance.

LONG TERM
Renin angiotensin-aldosterone: renin released by kidneys in response to low BP. Renin promotes angiotensin 2= vasoconstriction & aldosterone secretion.

ADH mech.- causes ADH release from post pituitary in response to low BP. Vasoconstriction & decreased urine output.

Atrial natriuretic mech.- a hormone released from cardiac cells in respond to high BP. Increase urine output= lower BV

Fluid shift mech.- movement of fluid between interstitial spaces and capillaries. Increase BV

Stress relaxation- adjustment of smooth muscle of blood cells in response to change in BP.