IB Biology Topic B3.2: Transport Questionbank

What is the function of elastic fibres in artery walls?

The graph compares coronary blood flow during equal exercise; arterial oxygen content is equal. Which change is expected with occlusion?

The figure shows one vascular bundle in a dicot stem. Which label-adaptation pairing identifies the tissue carrying water under tension?

It recoils after pressure peaks to maintain flow between pulses

It contracts actively at pressure peaks and stops flow

It remains stretched between pulses and lowers blood flow

It shortens diffusion distance for exchange with tissues

To restrict blood flow to non-essential organs

To stretch and recoil to maintain consistent pressure

To actively pump blood during diastole

To withstand high pressure without bursting

Less lactate; aerobic respiration increases

Unchanged lactate; arterial oxygen content is equal

More lactate; anaerobic respiration increases

Less lactate; coronary blood becomes deoxygenated

X; lignified walls resist collapse under transpiration tension

X; flexible walls allow stretching as water pressure rises

Y; lignified walls resist collapse under transpiration tension

Y; flexible walls permit collapse under tension