USA quiz · Grade 9

Grade 9 Biology quiz

16 practice questions. Tap an answer, then use the list below to study with a parent or teacher.

Question and answer list

Open a card to see the answer. These are original practice items for US elementary students — not a state test copy.

1. Osmosis is the diffusion of

Answer: water across a membrane

Water moves toward higher solute concentration.

2. Mitosis is used for

Answer: growth and repair of body cells

Daughter cells are genetically alike.

3. The cell cycle includes

Answer: interphase and mitosis

DNA is copied in S phase.

4. Ribosomes

Answer: make proteins

They read RNA.

5. Prokaryotes such as bacteria

Answer: lack a nucleus

Their DNA is in the nucleoid region.

6. A hypotonic solution can cause an animal cell to

Answer: swell

Water enters the cell.

7. ATP is

Answer: an energy-carrying molecule

Cells use ATP to do work.

8. The cell theory says

Answer: all living things are made of cells

Cells come from other cells.

9. Photosynthesis mainly occurs in

Answer: chloroplasts

Chlorophyll captures light.

10. The overall products of photosynthesis are

Answer: glucose and oxygen

6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂.

11. Plants take in carbon dioxide through

Answer: stomata

Guard cells open and close stomata.

12. The energy source for photosynthesis is

Answer: sunlight

Light energy becomes chemical energy.

13. Chlorophyll appears green because it

Answer: reflects green wavelengths

It absorbs red and blue light more.

14. Cellular respiration

Answer: breaks down glucose to make ATP

It is roughly the reverse energy path of photosynthesis.

15. A limiting factor for photosynthesis can be

Answer: light intensity, CO₂, or temperature

Too little light slows the rate.

16. Oxygen released by plants comes mainly from

Answer: water

Light reactions split water.