B1

Question 1

active transport

Answer 1

the movement of substances from a dilute solution to a more concentrated solution against a concentration gradient, requiring energy from respiration

Question 2

algae

Answer 2

simple aquatic organisms (protista) that make their own food by photosynthesis

Question 3

alveoli

Answer 3

tiny air sacs in the lungs that increase the surface area for gaseous exchange

Question 4

bacteria

Answer 4

single-celled prokaryotic organisms

Question 5

cell membrane

Answer 5

the membrane around the contents of a cell that controls what moves in and out of the cell

Question 6

cell wall

Answer 6

the rigid structure around plant and algal cells. It is made of cellulose and strengthens the cell

Question 7

cellulose

Answer 7

the complex carbohydrate that makes up plant and algal cell walls and gives them strength

Question 8

chlorophyll

Answer 8

the green pigment contained in the chloroplasts

Question 9

chloroplasts

Answer 9

the organelles in which photosynthesis takes place