7.3 circulatory system of a mammal

Question 1

explain why large organisms move substances around their bodies.

Answer 1

• small surface area to volume ratio

- large diffusion pathway

Question 2

describe the features of the transport systems of large organisms.

Answer 2

• suitable medium to carry materials
• form of mass transport in which the transport medium is moved around
• a closed system of tubular vessels that contain transport medium
• mechanism for moving the transport medium within vessels

Question 3

describe the circulatory system of mammals.

Answer 3

• closed, double circulatory system