Kategorier: Alle - valves - blood - heart

av shwe eaindray 11 år siden

3364

bio concept map- transport in humans

The human circulatory system involves the heart, blood vessels, and blood. The heart features distinct chambers such as the left and right atria and ventricles, which play crucial roles in pumping oxygenated and deoxygenated blood.

bio concept map- transport in humans

bio concept map- transport in humans

BLOOD VESSELS

thin walls that are only one cell-thick allow gases to move through to body tissues easily and at a fast rate
the exchange of gases, nutrients and metabolic waste products takes place through capillary walls by diffusion.
Capillaries
Single-layer of cells
Veins
Have valves

ensures blood flows in one direction, preventing backflow of blood

Carries blood from organs to lungs
Carries deoxydenated blood (except pulmonary vein)
Thin walls

stretchable

blood pressure in the veins is much lower than in arteries

Arteries
No valves
Carries blood from heart to organs
Carries oxygenated blood (except pulmonatory artery)
Thick walls

elasticity enables walll to stretch and recoil

to withstand high pressure of blood flowing through from heart

BLOOD

plasma
nutrients, carbon dioxide, waste products (e.g. urea) produced by body cells are transported through the body in the plasma
platelets
Irregularly shaped
cytoplasmic fragments of a large cell (megakaryocyte) produced by the bone marrow
prevent excessive blood loss by causing clotting to occur
white blood cell
phagocyte

produces by bone marrow, lobed nucleus, granular/ non granular cytoplasm, engulfs and digest bacteria in process called phagocytosis

lymphocyte

produced by lymph nodes, round nucleus non granular cytoplasm, produces antibodies during invasion by foreign particles

becomes memory cells that can recognise same invaders

body becomes immune

immune system reacts to the pathogen by producing antibodies against it

administering weekend or deadpathogens to healthy person

agglutination of foreign bodies

attach and bind to the foreign bodies

neutralise toxins

leucocytes

to protect the body against infections and diseases

colourless, irregular in shape, able to squeeze through pores in capillary wall to reach site of infection, has nucleus

red blood cell
acclimatisation occurs when body produces more red blood cells which contains haemoglobin to carry more oxygen so as to compensate for the lower concentration of oxygen breathed into the body with each breath
thin flexible membrane

enable bending through narrow capillaries

no nucleus

increased volume for absorption of oxygen

biconcave shape

increased surface area for absorption of oxygen

has haemoglobin

iron containing protein complex found in red blood cells which has high affinity for oxygen; carries oxygen

HEART

septum
prevent mixing og oxygenatedand deoxygenated blood
left
ventricle

most muscular, excert very high pressure on blood, pump oxygenated blood from heart to all parts of body

receive oxygenated blood from pulmonary vein and pump into left ventrivle

biscupid valves

right
ventricle

less muscular, pump deoxygenated blood to lungs

atrium

receive deoxygenated blood from vena cava and pump into right ventricle

triscupid valves