transport in animals Flashcards
why do we need transport systems
they have a large distance between cells and surfaces
we have adapted transport systems to:
-meet high metabolic demands
-overcome decreasing SA:V
-allow movement of hormones
-remove waste products of metabolism
open circulatory systems?
the transport system only transports food and waste products not gas exchange
usually found in vertebrates eg. insects
closed circulatory?
comes in two forms : single (heart with two chambers) and double ( heart with four chambers)
closed circulatory systems have higher pressure and lower metabolic demand
arteries?
-carry’s blood away from the heart
-high pressure
-elastic tissue to allow them to recoil and smooth blood flow
arterioles
branch off arteries
thinner less muscular walls then artieries
job is to feed blood to capillaries
venules
thin walls larger then capillaries but smaller then veins
veins
carry blood to the heart high
have a wide lumen
blood is at low pressure
contains valves to prevent backflow of blood
what is tissue fluid
its a liquid with dissolved oxygen and nutrients which supply the tissues with the essentials in exchange for waste products like CO2
it enables exchange of substance between blood and cells
hydrostatic pressure
its created when blood is pumped along the arteies into arterioles and then cappliaries
it forces blood fluid out of the capillaries
oncotic pressure
the fluid is also acted on by oncotic presssure (tendency of water to move through the blood b by osmosis) which pull pushes some of the fluid back into the capillaries which is negative water potential as the tissue fluid and the blood contains solutes
Lymphatic system
The remaining tissue fluid is carried to the lymphatic system which contains lymph fluid and less oxygen and nutrients compared to tissue fluids. Its main purpose is to carry waste products. The lymph system also contains lymph nodes which filter bacteria and lymphocytes which destroyed the invaders as part of the immune defence system.
sinoatrial mode
pacemaker of the heart
causes electrical stimulation
so atria can contract at the same time
it’s in the right atrium
Number 1. cardiac cycle
during atrial system, the atria contract and this forces the atrial ventricular valves open and blood into the ventricalers
ventricular systole?
Contraction of the ventricle causes the atrio-ventricular valves to close and the semilunar valves to open this allowing blood to lead the left ventricle through the Toyota on the right ventricle called through the pulmonary artery
cardiac diastole
Atria and ventricles relax elastic recoil of the heart lowers the pressure inside the heart chambers and blood is drawn from the arteries and veins this causing semilunar valves in the aorta and pulmonary arteries to close preventing backflow of blood
Equation for cardiac output
cardiac output = heart rate x stroke value
Bradycardia
Heart rate under 60 BPM
Tachycardia
Heart rate under 100 BPM
Atria fibrillation
arrhythmia -abnormal rhythms of the heart they are rapid electrical impulses in the atrium leading to the atria not contracting properly and the heart does not efficiently pump blood
Haemoglobin
haemoglobin carries oxygen in the blood so oxygen combined to the haem group (Fe) and oxygen is released when required. It can hold two 02 molecules (eight in each haemoglobin.)
affinity for oxygen
Affinity for oxygen for haemoglobin depends on partial pressure of oxygen saturation carbon dioxide
