3.2 Transport in animals Flashcards
What are the 3 main factors that influence the need for a transport system?
- size
- SA:V
- metabolic activity
What are some features of a good transport system?
- a fluid or medium to carry nutrients, oxygen and water (blood)
- a pump to create pressure (heart)
- exchange surfaces (capillaries)
What is a single circulatory system?
The blood flows through the heart once for each circuit
heart > gills > body > heart
What animals have a single circulatory system?
Fish
What is a double circulatory system?
The system has two separate circuits: pulmonary which carries blood to lungs for oxygen and systemic that carries nutrients around the body
heart > body > heart > lungs > heart
What animals have a double circulatory system?
Mammals
What are some disadvantages to a single circulatory system?
- blood pressure drops in the capillaries of the gills
- blood has low pressure flowing towards the body
- the rate of oxygen and nutrient deliveries is limited
What are some advantages of a double circulatory system?
- the heart can create high blood pressures
- systemic circulation can withstand higher pressures than pulmonary circulation
Why do mammals need a better circulatory system than fish?
mammals are more metabolically active and require more nutrients, especially to maintain body temperature
What is the stuff going from inside out of artery and vein?
lumen, endothelium, elastic fibres, smooth muscle, collagen fibres
describe a capillary
lumen and endothelium
how is tissue fluid formed?
at high hydrostatic pressure, plasma goes out of capillary. Excess goes to lymphatic system
what remains in the blood at the capillaries?
white blood cells and plasma proteins
sthg about onctoic pressure
sheet
what artery goes into the right atrium?
pulmonary artery
