Grade 7 Cell Biology

Unlike Hooke, Leeuwenhoek observed cells that

• had no cell walls.

• came from plants.

• were alive.

• could only be seen with a compound microscope.

What is the function of a cell wall?

• to protect and support the cell

• to perform different functions in each cell

• to prevent water from passing through it

• to prevent oxygen from entering the cell

A substance that cannot be broken down into simpler elements is a(n)

• particle.

• element.

• carbohydrate.

• compound.

Enzymes are important because they

• contain water.

• speed up chemical reactions.

• contain genetic material.

• help the cell maintain its shape.

What is the basic unit of structure and function in a living thing?

• a cell

• a tissue

• an organ

• an organ system

The invention of the microscope made it possible for people to discover

• plants.

• skin.

• animals.

• cells.

A microscope allowed Hooke to see “tiny rectangular rooms,” which he called _______.

• cells

• atoms

• molecules

• particles

Small grain-like bodies called _______ produce proteins inside cells.

• ribosomes

• mitochondria

• chloroplasts

• lysosomes

A light microscope that has two or more lenses is called a(n) _______ microscope.

• compound

• simple

• electron

• digital

_______ is formed when two or more elements combine chemically.

• A compound

• A mixture

• An atom

• A solution