Gas Exchange in Fish and Plants (AQA A level Biology)

What is the concentration of oxygen in water?

• 1%

• 20%

• 0.01%

• 80%

How many pairs of gills does a fish have?

• 1

• 2

• 3

• 4

What are the 'ridges' (which increase surface area) on gill filaments called?

• lumen

• lamellae

• alveoli

• leaves

Which term is used to describe the opposite flow of blood and water across gills?

(a)  

Which layer of cells in a leaf carries out the most photosynthesis?

• spongy mesophyll

• epidermis

• waxy cuticle

• palisade mesophyll

What is the name of the cells which control the opening of stomata?

(a)  

Which of the following are features found in xerophytes?

• rolled leaves

• sunken stomata

• leaf hairs

• lots of stomata

Which surface of a leaf generally has the most stomata?

• lower

• upper

In which habitats can xerophytes be found?

• deserts

• tundra

• salt marshes

• sand dunes

Which of the following are xerophytes?

• oak trees

• cacti

• geranium

• marram grass