Heart, Blood and Immunity Flashcards
What is blood?
A free-flowing liquid, composed of plasma and other substances.
What are the two main types of leucocytes (white blood cells)?
phagocytes and lymphocytes
What are platelets, and what is their role?
tiny cell fragments that help in blood clotting
What is the shape of a red blood cell and why is it that shape?
biconcave disc for increased surface area, helping in efficient exchange of oxygen in and out of the red blood cell
What is the concentration of plasma in the blood?
55%
What is the concentration of red blood cells in the blood?
44%
What is the concentration of lymphocytes in the blood?
0.3%
What is the concentration of phagocytes in the blood?
0.5%
What is the concentration of platelets in the blood?
0.2%
Describe the functions of the plasma.
circulation of dissolved nutrients (eg glucose and amino acids), mineral ions and waterremoval of waste products (eg lactic acid and carbon dioxide)transportation of hormones (glands to target cells)keeps body temperature regulated
What is plasma?
a liquid medium making it possible for blood cells to float and molecules to dissolve
What is the function of the red blood cell?
carries and transports oxygen in the form of oxyhaemoglobin, and it has no nucleus in order to have more space
What is the function of a lymphocyte? How is it adapted to its function?
produces antibodies to combat antigens, contains a large nucleus to produce antibodies effectively
What is the function of a phagocyte? How is it adapted to its function?
carries out phagocytosisirregular and multi-lobed nucleus cytoplasm that contains digestive enzymes that can be released during phagocytosis
Describe the blood clotting process.
wounds, like cuts, could potentially allow the entry of pathogens in the bodyplatelets release clotting factorsthe clotting factors lead to fibrinogen (soluble protein in plasma) to become fibrin (insoluble protein in plasma)fibrin forms a mesh of fibres that capture both platelets and blood cellsthis forms a clot over the wound, which dries to become a scab
Describe the process of phagocytosis.
phagocytes are attracted to the area in which there are pathogens invading the bodyphagocytes engulf the pathogenenzymes in the phagocyte’s cytoplasm digest the pathogenthese enzymes break the pathogen down into molecules called antigensantigens are either absorbed, exposed at the cell surface or expelled from the cell
What type of organ is the heart?
myogenic
What is phagocytosis?
process in which phagocytes extend their cell membranes to engulf and digest pathogens
What are the blood vessels that carry blood towards the heart?
veins
What are the blood vessels that carry blood away from the heart?
arteries
What is the function of the vena cava, and where is it located?
it brings blood from the rest of the body to the heartit is on the right side of the heart
What is the function of the aorta and where is it located?
sends blood from the heart to the rest of the bodyit is on the left side of the heart
What is the function of the valves?
control direction of blood flow by closing when blood fills up the ventricle
Which structure of the heart is found at the top on both its sides?
the atriums
Which structure of the heart is found at the bottom on both its sides?
the ventricles
What are coronary arteries?
arteries that provide blood to the heart and can cause heart attacks when blocked with too much fat deposits
Which vessels carry oxygenated blood?
aorta, pulmonary vein
Which vessels carry deoxygenated blood?
vena cava, pulmonary artery
Name four differences between a single and a double circulatory system.
double: two complete body circuits (passes through heart 2x before reaching other organs)double has four chambers instead of twodouble pumps deoxygenated and oxygenated blood, not only deoxygenateddouble has a very high pressure of oxygenated blood, unlike in a single
What is the main function of the right side of the heart?
pump deoxygenated blood to the lungs
What is the main function of the left side of the heart?
pump oxygenated blood to whole body except lungs
What are factors that increase the risk of coronary heart disease?
stress, bad diet, low exercise, smoking, diabetes, age, family smoking history…
What type of blood do arteries carry? What is an exception?
they carry oxygenated bloodpulmonary artery is an exception
What type of blood do veins carry? What is an exception?
they carry deoxygenated bloodpulmonary vein is an exception
Which blood vessel contains valves?
vein
Which has the highest blood pressure, capillary, vein or artery?
artery - high pressurevein - low pressurecapillary - very low pressure