SB8-Exchange and transport in animals Flashcards
How do many substances move into and out of parts of the body?
Diffusion
What is needed for aerobic respiration?
Oxygen and glucose
What adaptations do the surfaces that substances move through have?
Thin- so particles don’t need to diffuse very far
Large surface are-so there is more room for particles to diffuse
What transport system do humans use to transport substances to and from all cells?
The circulatory system- a fine network of capillaries use blood to do this
How many cells thick are capillaries?
One cell thick
How do you work out the surface area:volume ratio?
Surface area/volume
What do lungs have millions of?
Alveoli
What do alveoli do?
Increase the surface area, increase the speed and increase the amount of gas exchange
What is the formula for concentration?
Concentration = mass of solute (g) / volume of solution (dm3)
What is the formula for the rate of diffusion?
(Surface area x concentration difference) / thickness of membrane
What is the path of blood entering and then leaving the heart?
Veins carry blood back to the heart
A
V
A
What do valves do?
Prevent blood flowing the wrong way
How does blood from the heart and the lungs travel through the heart?
Blood from most of the body enters through the vena cava to the right atrium
Blood from the lungs enters the left atrium through the pulmonary vein
When these chambers are full, the muscles around them contract, pushing the blood into the ventricles
Muscles in the ventricle walls then contract, forcing blood out the heart
Muscles in the atria walls relax and the chambers refill with blood
What is a heart rate and what is it measured in?
The number of times the heart beats a minute (beats/min)
What is a heart attack?
When blood stops flowing to muscles in part of the heart, damaging them and preventing the heart from pumping properly