O-Level Combined Science — Biology 2 — Questions and Answers
Question 1: What is the process by which water moves from an area of high water potential to low water potential through a semi-permeable membrane?
- Diffusion
- Active transport
- Osmosis (Correct answer)
- Transpiration
Correct answer: Osmosis
Osmosis is the net movement of water molecules through a partially permeable membrane from an area of higher water potential to lower water potential.
Question 2: Which part of the plant absorbs water and minerals from the soil?
- Leaves
- Stem
- Root hair cells (Correct answer)
- Stomata
Correct answer: Root hair cells
Root hair cells have a large surface area and thin walls to maximise absorption of water and mineral ions from the soil.
Question 3: What is the role of enzymes in the body?
- To provide energy
- To act as biological catalysts (Correct answer)
- To transport oxygen
- To build cell walls
Correct answer: To act as biological catalysts
Enzymes are biological catalysts that speed up chemical reactions in the body without being consumed. Each enzyme has a specific substrate.
Question 4: What is the term for the variety of different species in an ecosystem?
- Adaptation
- Evolution
- Biodiversity (Correct answer)
- Ecology
Correct answer: Biodiversity
Biodiversity refers to the variety of life in a given area, including the number and variety of different species.
Question 5: Where does fertilisation occur in the human female reproductive system?
- Uterus
- Cervix
- Ovary
- Fallopian tube (Correct answer)
Correct answer: Fallopian tube
Fertilisation typically occurs in the fallopian tube (oviduct), where the sperm meets the egg after ovulation.
Question 6: What is a food chain?
- A web of interconnected food webs
- A sequence showing how energy passes from one organism to another (Correct answer)
- A list of all organisms in an ecosystem
- A diagram of the water cycle
Correct answer: A sequence showing how energy passes from one organism to another
A food chain shows the linear sequence of organisms through which energy and nutrients pass as one organism eats another.
O-Level Combined Science — Biology 2
What is the process by which water moves from an area of high water potential to low water potential through a semi-permeable membrane?