transport in man

What are the constituents of blood and in what percentage

Red blood cells 45 percent

White blood cells , platelets (less than one percent)

Blood plasma (55%)

Function of blood

Transport various substances from one part of the body to another

Protect body from disease causing organisms

Protect body through blood clotting at wounds

What is blood plasma

Pale yellow liquid consisting of mainly water and transports bloood consistuents around the body

how does haemoglobin in rbc work

It bindsreversibly with oxygen to form oxyhaemoglobin . When it’s in places with high conc of oxygen haemoglobin binds with oxygen and when in places with low conc of oxygen it releases oxygen

What exactly does bloody plasma transport?

Dissolved food substances amino acids fats vitamins, excretory products urea uric acid and hco3-, hormones like insulin glucagon and oestrogen , plasma proteins fibrinogens and antibodies, mineral salts ,na+ k+ ca2+

Function of rbc

To bind and transport oxygen around the body

What are the characteristics of the red blood cell and why

Circular biconcave shape to increase sa to v ratio for more efficient diffusion of oxygen in and out of cell

No nucleus so it has more space to contain haemoglobin molecules to transport more oxygen

Flexible so it allows them to squeeze and also change shape to fit through narrow capillaries to transport oxygen through blood capilarries

Function of white blood cell

To keep body healthy by protecting it against diseases

Characteristics and facts about wbc

Irregular shape colorless

Has a nucleus

Mostly produced in bone marrow

Has lymphocytes and phagocyte

Difference between lumphocytes and phagocytes and their functions

Lymphocytes large rounded nucleus

Produce antibodies to protect body

Phagocytes lobed nucleus

Perform phagocytosis , engulf and digest foreign particles. Ingested bacteria will be digested by enzymes in the phagocyte

Facts and characteristics of platelets

Not true cells

Fragments of cytoplasm bound by membrane

Function of platelets

Prevent excessive loss of blood cells

Preven bacteria from entering through wounds

How does platelets form blood clots

Damaged tissues and fibrinogen produced enzymes which make soluble fibrinogen change into insoluble fibrin threads after interacting with thrombin . These insoluble threads form a mesh of fibrin that entangles blood cells and that mass forms a clot

What are antibodies

Blood protein that reconsiders foreign particles and binds with them

Function of antibodies

Destroy foreign particles

Cause them to clump together

Neutralize toxins produced by foreign particles

What is tissue rejection

Transplanted tissues or organs can be regconized as foreign body by white blood cells and destroyed by antibodies of the recipients lymphocytes

What can be done to prevent tissue rejection

Screening to find donors with genetic composition as close to the recepients

Provide immunosuppressive drugs to inhibit responses of recepients immune responses

What happens when incompatible blood type is transferred and why what happen

Death . It will be caused by agglutination of recieversbantibodies regconisinh the blood as a foreign substance, resulting in clumping of donors blood which blocks blood flow in recipients body, leading to less flow of oxygen to cells and tissues in the body and eventual deprivation of oxygen for tissues surrounding the area

What is blood group ab and o known as

Universal acceptor and universal donor

How are capillaries formed

Branching of arterioles which units to form henukes which unit to form veins

Properties of arteries

Thick muscular wall, narrow lumen, carries oxygenated blood except pulmonary artery that carries deoxygenated blood from heart to lungs, elastic walls

Explain the purpose of the Arteries thick muscular walls, narrow lumen and elastic walls

Thick muscular walls. To withstand high pressure of blood forced out of the heart

Narrow lumen contributed to high blood pressure in arteries

Elastic walls. To stretch and recoil to withstand high bloood pressure

Why does blood flow in spurts to the Rotb

The elastic walls of the arteries transporting oxygenated blood to the rest of the body can stretch and recoil , withstanding the high blood pressure so that’s why

Characteristics of capillaries and why

One cell thick- allows substances to diffuse quickly thru its walls in and out of the capillary

Microscopic blood vessels found between the cells of almost all tissues - efficient exchange of substances between blood and tissues cells

Very narrow lumen,

Branches repeatedly to form extensive networks- to increase sa to v ratio for more efficient exchange of substances between bloood and tissue cells

Lower bloood pressure and slower flow of blood - allows for more time for exchange of substances between blood and tissue cells to occur

Characteristics of veins

Thinner walls, less elastic walls, wider lumen, and valves to prevent back flow of blood, carries deoxygenated blood except pulmonary vein, lower blood pressure

why do veins have valves

Contractions of heart muscles itself is not enough for blood to be returned to the heart

Function of veins and arteries

Veins carry. Blood toward heart

Arteries carry blood away from heart

Major blood vessels in human body and where are they or what do they do

Arteries away from heart

Veins toward heart

Pulmonary -lungs

Renal- liver

Hepatic- kidneys

Why are the right and left side of the heart seperated by the median septum

Prevents mixing of oxygenated bloood and deoxygenated blood as this reduces amt of oxygeneated blood transported to the rotb

What does the right atrium, right ventricle, left atrium and left ventricle of the heart recieve or do and bloood vessels involved

Right atrium receives deoxygenated blood from rest of the body through vena cava

Right ventricle pumped deoxygenated blood into the lungs through the pulmonary artery

Left atrium receives oxygen from the lungs through the pulmonary vein

Left ventricle pumps oxygen to the rest of the body through the aorta

why are the ventricular walls more muscular than the atrial walls

Ventricles pump blood out of the heart to the rest of the body/ lungs. If needs a more muscular walls to generate higher pressure to pump blood for a longer distance .

They also need them to withstand the hbl in ventricles. Atria only force blood into the ventricles which are a shorter distance away, and do not require high blood pressure

Why is the left ventricle wall thicker than the right ventricle wall

The right ventricle has thinner walls as it pumps blood to lungs which is a shorter distance away when left ventricle needs thicker walls to generate as well as withstand higher pressure as it pumps blood thru aorta all round the body which is. A further distance away

what are the different valves in the heart and what do they do

Semilunar valve prevents back flow of blood from the arteries to the ventricles

Tricuspid valve prevents back flow of blood from the right ventricle to the right atrium

Bicuspid valve prevents back flow of blood from the left ventricle to the left atrium

What is the chordae tendineae and what does it do

Inelastic chords of tissue that connect the tricuspid valve to the walls of the ventricles which allow the halves to open and close in the correct positions

Overview of blood flow through the heart

• Atrial and ventricular muscles relaxed

• Blood enters atria, passively flow into ventricles when bicuspid valve and tricuspid valve is open

• Atria muscles contract contract forcing remaining blood into the relaxed ventricles

• After a short pause the ventricle muscles contract, the semilunar valves are forced open .

• Bicuspid and tricuspid valves are forced closed

• Blood flows out from the right ventricle and left ventricle into the pulmonary artery and aorta

• Semilunar valves are forced closed

• The atria muscles relax and now recieved blood from the rotb and lungs. ( vena cava , pulmonary veins)

• Ventricle muscles relax and atrio bentricular valves open, and blood flows from the atria into the ventricles

• Cycle repeats

what is blood pressure and how is it measured

It is the force that blood exerts in the walls of blood vessels and it’s measured with a sphygmomanometer

Where do the conorary arteries lie and what do they do

They lie outside of the hearrt, transporting blood to heart muscles

What is conorary heart disease

It is the narrowing or blockage of conorary arteries reducing blood supply to heart muscles, less supply of oxygenated blood to heart muscles.

What is atherosclerosis and thrombosis

Atherosclerosis the deposits of fatty substances in the inner surface of arteries

Thrombosis blood clot trapped in artery

what happens when arteries are narrowed by fatty deposits

Reduced supply of glucose and o2 , reduction in blood flow to heart muscles. This causes the heart to be unable to carry out aerobic respiration efficiently, also decreases release of energy for heart muscles cells which increases heart attack risk. When heart muscle cells die, heart can no longer pump blood

What are the causes of Chd and what can be used to prevent it

Diet rich in saturated fats and cholesterol- reduce intake of saturated fats and cholesterol and replace with polyunsaturated fats

Smoking- quit smoking do not smoke

Lack of exercise - regular exercise, strengthens heart muscles maintains elasticity of arterial walls

Function of capillaries

Exchange of substances between blood and tissue cells