Unit 3: Size and surface area

Question 1

What does an animals SA:V ratio affect?

Answer 1

How quickly substances are exchanged

Question 2

Smaller organisms have a 1___ SA:V ratio than larger organisms

Answer 2

1. Smaller

Question 3

SA of a cube

Answer 3

LxWxHx6

Question 4

Area of a circle

Answer 4

Pi x R squared

Question 5

Circumference of a circle

Answer 5

2 x R x Pi

Question 6

SA of cuboid

Answer 6

2LW+2WH

Question 7

SA of a cylinder

Answer 7

2Pir squared + 2Pirh

Question 8

SA of a sphere

Answer 8

4piR squared

Question 9

Volume of cube and cuboid

Answer 9

L X W X H

Question 10

Volume of cylinder

Answer 10

PiR squared H + 4/3 Pi R cubed

Question 11

Volume of a sphere

Answer 11

4/3 Pi R cubed

Question 12

Define surface area

Answer 12

the total area of the organism that is exposed to the external environment

Question 13

Define volume

Answer 13

the total internal volume of the organism (total amount of space inside the organism)

Question 14

As the surface area and volume of an organism 1._____ (and therefore the overall ‘size’ of the organism increases), the surface area : volume ratio 2.____
Explain why

Answer 14

1.increase
2. decreases
-volume increases much more rapidly than surface area as size increases