LO1 Flashcards
what are the key features and functions of erythrocytes? (red blood cells)
- made in the bone marrow
- bi-concave shape, round and flattened with a central indentation to maximise the surface area for exposure to oxygen
- transport oxygen and carbon dioxide within the body
- do not have a nucleus which increases space to carry the maximum amount of haemoglobin
- haemoglobin combines with oxygen so erythrocytes are able to transport more oxygen
- small and flexible, allowing them to get into narrow blood vessels called capillaries
what are the key features and functions of leukocytes? (white blood cells)
- immune cells that defend the body against infection
- detect abnormal material and destroy it
what are the key features and functions of lymphocytes?
- 2 types
- B cells develop in the bone marrow
- B cells produce antibodies to destroy antigens such as bacteria, viruses and toxins
- T cells develop in the thymus gland and destroy the body’s own cells that have been taken over by viruses or have become cancerous
what are the key features and functions of neutrophils?
- Small and fast
- One of the first cell types to travel to the site of infection
- Protect the body against bacterial infection
- Highly mobile and attracted to any area of infection by chemicals produced by damaged cells
what are the key features and functions of monocytes?
- the largest of the white blood cells
- Originally formed in the bone marrow
- Released into the blood and tissues
- When certain germs enter the body, they quickly rush to the site for attack
what are the key features and functions of platelets?
- Produced in the bone marrow
- Fragments of larger cells
- Disc shaped
- Help to form blood clots by clumping together to slow or stop bleeding and to help wounds heal
what are the key features and function of the plasma?
- largest component of blood (55%)
- clear yellow-ish coloured liquid
- carries platelets, red blood cells, white blood cells and proteins
- provides a means of transport for glucose, lipids, amino acids, hormones, dissolved food molecules, carbon dioxide and oxygen
- carries proteins including fibrinogen which helps with blood clotting
- helps with temperature regulation of the body - blood removes heat from tissues such as muscles and circulates it around the body
what are the 5 main function of blood?
- transport
- temperature regulation
- exchange of materials with body tissue
- preventing infection
- blood clotting
temperature regulation
- the process of thermoregulation maintains optimum body temperature
- the blood plays a role in thermoregulation
- it distributes heat throughout the body, from the core to the surface and vice versa
transport
- blood vessels are where delivery and waste removal takes place
- oxygen, nutrients and hormones are delivered around the body in the blood and carbon dioxide and other waste products are removed
exchange of materials with body tissues
- capillaries allow exchange of substances with body tissues through their thin walls
- as blood travels at high pressure in the arteries towards the capillaries, pressure filtration occurs which results in plasma passing through the capillary wall into the tissue fluid which surrounds the cell
- tissue fluid provides cells with useful substances such as glucose and oxygen and waste products are passed out of the cells into the tissue fluid to be removed
- most of the tissue fluid is returned to the blood. any excess tissue fluid is absorbed by lymphatic vessels which return it to the circulatory system as lymph.
- plasma and tissue fluid are composed of similar substances except for plasma proteins which is only found in plasma. They are too large to be filtered through the capillary walls
preventing infection
- white blood cells are immune system cells
- they are ready to attack invaders such as bacteria and viruses
- when fighting infection, the body produces more white blood cells
blood clotting
- an important process that prevents excessive bleeding when a blood vessel is injured
- platelets and proteins in your plasma work together to stop the bleeding by forming a clot over the injury
describe the pathway of blood
deoxygenated blood enters from the vena cava into the right atrium.
blood collects in the right atrium until it is full and then starts to squeeze through the tricuspid valves into the right ventricle.
blood is then pushed through the pulmonary valves into a vessel called the pulmonary artery to the lungs.
oxygenated blood from the lungs passes through the pulmonary vein and collects in the left atrium.
the blood then passes through the mitral valves into the left ventricle.
the blood is then forced into the aorta through the aortic valves.
what are the 14 parts of the heart?
superior vena cava
pulmonary veins
right atrium
tricuspid valve
pulmonary valve
right ventricle
inferior vena cava
myocardium
aorta
pulmonary artery
left atrium
mitral valve
aortic valve
left ventricle
what is the function of the superior vena cava?
a large vein that carries blood from the upper body to the heart
what is the function of the pulmonary veins?
takes blood from the lungs into the left atrium of the heart
what is the function of the right atrium?
deoxygenated blood enters the right atrium through both vena cava
what is the function of the tricuspid valve?
separates the right atrium and the right ventricle
what is the function of the pulmonary valve?
separates the pulmonary artery and the right ventricle
what is the function of the right ventricle?
pumps deoxygenated blood to the lungs through the pulmonary artery
what is the function of the inferior vena cava?
a large vein that carries blood from the lower body to the heart
what is the function of the myocardium?
this is the muscular wall of the heart, it contracts to pump blood
what is the function of the aorta?
a large artery that carries blood from the heart to the body
what is the function of the pulmonary artery?
carries blood from the right ventricle to the lungs for oxygenation
what is the function of the left atrium?
blood enters the left atrium from the pulmonary vein
what is the function of the mitral valve?
separates the left atrium and the left ventricle
what is the function of the aortic valve?
separates the left ventricle and aorta
what is the function of the left ventricle?
pumps oxygenated blood to the body through the aorta
what is the function of semilunar valves?
these valves close as the heart pumps blood into the pulmonary artery and the aorta.
they close to prevent the backflow of blood and the lub-dub sounds of the heart is these valves opening and closing.