Blood,The heart and the circulatory system

what does blood do?

-transports O2 & nutrients to body cells & carries away CO2 & metabolic wastes

-helps protect body from diseases(white blood cells)

-is a tissue

blood plasma

The liquid part of the blood containing useful things like: glucose, amino acids, minerals, vitamins (nutrients) and hormones, as well as waste materials such as urea.

-distributes heat and makes up 55% of blood

straw like colour(mainly yellowish)

Haemoglobin

in red blood cells that carries oxygen for delivery to cells(red blood cells have alot of this causing their red colour)

oxygen + haemoglobin --> oxyhaemoglobin

red blood cells

Transporting oxygen required for aerobic respiration in body cells

-make up 40% of our blood

-absorbs oxygen in the lungs and pass through the capillaries

and released respiring cells

-have a biconcave shape allowing them to carry more oxygen (higher SFA)

-no nucleus which allows them to carry more hemoglobin

-small and flexible to fight through narrow capillaries

-thin so shorter distance for oxygen to diffuse and reach the center of the cell

White blood cells

-make up <1 of our blood(with platelets)

-Ingesting pathogens(phorocytes do this) and producing antibodies(special chemicals which either stick and kill pathogens-lymphocytes do this)

-help the body fight against infection

-can change shape, so they can squeeze out of the blood vessels into tissues or surround and engulf microorganisms

Platelets

-Involved in blood clotting in an event of a wound by acting on protein called fibrinogen which in turn forms abrin fibers

-under 1 % of blood(white blood cells included)

aerobic respiration

Respiration that requires oxygen

anerobic respiration

Respiration that does not require oxygen

oxygen

Gaseous element making up about 20% of the air, which is needed by living organisms for respiration.

arteries

-carry blood away from the heart to organs so high blood pressure

-thick walls made from muscle and elastic fibers to prevent lumen form bursting due to the high blood pressure

veins

-carry blood back into the heart

-wide lumen and thin muscle walls due to low blood pressure

-valves to prevent backflow

capillaries

-receive blood from the arteries and veins

-located within the tissues of the body and carries blood to body cells

-allows substances need by cells to pass out of the blood so its permeable and substances produced by cells to pass into the blood

-Narrow lumen ,thin-walled blood vessels and low blood pressure(gives time for diffusion)

chemical reaction in the lungs for oxygen and haemoglobin

haemoglobin + oxygen -> oxyhaemoglobin

chemical reaction in the tissues for oxygen and haemoglobin

oxyhaemoglobin -> haemoglobin + oxygen

Double circulatory system

Blood passes through the heart twice in one complete circuit of the body

the heart

-pumps blood in a double circulatory system

-4 chambers of the heart:

-left and right atria, which receive blood form veins

-left and right ventricles, which pump the blood out into arteries

circulation of blood in the heart

-blood enters the heart through the atria

-the atria contract and force blood into the ventricles

-ventricles then contract and force blood out of the heart(through the aorta to body or the pulmonary artery to the lungs)

-valves in the heart make sure the blood is flowing through the right direction

pacemakers

-group of cells located in right atrium controlling the natural resting heart rate

-coordinate the contraction of the heart muscle thus it regulates the heart rate

-pace makers send out an electrical impulse which spread to the surrounding muscle cells of the heart, causing them to contract

-does this when the heart needs to beat so if resting heart is 60 bpm then the pacemaker will do these electrical impulses once a second

low and high heart rates

-when a person is at rest the oxygen demanded of their cells is relatively low so a lower heart rate is maintained

-when a person is exercising, the oxygen demand of muscle cells increases so a higher rate is necessary

pulmonary artery

Carries deoxygentated blood from the heart to the lungs

pulmonary vein

carries oxygenated blood from the lungs to the heart

heart diseases

-artifical pacemakers-used if someones natural pace maker cells are not working

-replacement heart valves-for fault heart valves

-artificial hearts-to use in heart transplants

-hole in the heart- opening in the wall of heart

avg heart rate

60-100 bpm