The Circulatory System Flashcards
Biconcave
1 mark
Surface that curves inwards on both sides.
Blood plasma
7 marks
Liquid part of the blood containing useful things like -
- Glucose
- Amino acids
- Minerals
- Vitamins (nutrients)
- Hormones
as well as waste materials such as urea.
Cardiac output
Amount of blood pumped by the heart in one minute.
Heart Rate x Stroke Volume = Cardiac Output.
Deoxygenated
3 marks
Blood that is -
Low in oxygen (as cells have used it)
+ High in CO2 (as cells have produced it).
Lumen
2 marks
Central cavity of a hollow structure in an organism or cell.
Oxygenated
(1 mark)
Blood
- high in O2
- and low in CO2.
Urea
3 marks
A nitrogenous waste product resulting from the breakdown of proteins.
It is excreted in urine.
Valve
1 mark
Structure in veins that prevents the backflow of blood.
The circulatory system has three main components:
3 marks
Blood
Blood vessels
The heart
2 Main Functions of Circulatory System
2 marks
Transportation of substances
Protection against disease
Function of Red Blood Cells
1 mark
Carry oxygen.
Function of White Blood Cells
1 mark
Defend the body against disease.
Function of Platelets
2 marks
Convert fibrinogen to fibrin - to clot blood/form a scab.
Fibrin
3 marks
Forms a mesh that traps blood - important in blood clotting + scab formation.
Function of Plasma
5 marks
Transports;
Blood Cells, Digested food molecules, CO2, Urea \+ Hormones.
Example of digested food Molecules
1 mark
Glucose
Red Blood Cells Structure
6 marks
Contain haemoglobin (rich in iron) to carry O2.
Biconcave shape - provides large surface area for diffusion of O2.
No nucleus - provide more space for haemoglobin.
Haemoglobin
2 marks
Rich in iron - required to carry O2 in RBC’s.
White Blood Cells Structure
3 marks
Large cells that contain a nucleus.
2 types - Lymphocytes + Phagocytes
Lymphocytes
1 mark
Make antibodies.
Phagocytes
2 marks
Engulf + digest microorganisms.
Platelets Structure
1 mark
Cell fragments (very small).
Plasma Structure
1 mark
Straw coloured liquid.
Cell Lysis in RBC’s
6 marks
RBC’s placed in a high conc. of water -
osmosis will cause water to move into cell + without a cell wall = they lyse (burst).
Salts + other chemicals are present in the blood plasma - keep its conc. similar to conc. of blood cells.
Present in the blood plasma - keep its concentration similar to the concentration of blood cells.
(2 marks)
Salts + other chemicals
Main Vessels
3 marks
Artery
Vein
Capillary
Artery direction of blood flow
1 mark
Away from the heart.
Vein direction of blood flow
1 mark
Towards the heart.
Capillary direction of blood flow
1 mark
From artery to vein.
Lumen diameter in artery
1 mark
Small
Lumen diameter in vein
2 marks
Large - reduces friction as the blood moves through.
Lumen diameter in capillaries
1 mark
Small