SAFOLO — 2h.1 — Transport

Question 1

Unicellular organisms?

Answer 1

Organisms composed of a single cell — bacteria, fungus, yeast

Question 2

Movement of substances in and out of unicellular organisms?

Answer 2

• Large SA:V ratio = efficient rate of diffusion (cell relies solely on diffusion to transport necessary substances in and out of the cell)
• Thin cell walls (one cell thick) smaller distance of diffusion
• Moist membranes to allow substances to diffuse easily

Question 3

Transport system?

Answer 3

A system that provides a constant supply of necessary substances through a medium to cells via an exchange surface - e.g circulatory system

Question 4

Multicellular organisms?

Answer 4

Organisms made of more than one cell — humans

Question 5

Movement of substances in and out of multicellular organisms?

Answer 5

• Small SA:V ratio = inefficient rate of diffusion cell can’t rely on diffusion only (so they rely on transport systems)

Question 6

Common features of transport systems?

Answer 6

• Tubes or vessels: carry necessary substances from one part of organism to another in a structured process
• Close contact with cells: exchange surface for efficient exchange of necessary substances
• Pumps: ensure a constant supply of necessary substances to cells - the heart acts as a pump to ensure the constant circulation of blood by which materials are transported by in the human circulatory system