Grade 10 biology – introduction to Biology Quiz
1. Which of the following is a characteristic of all living organisms?
All living organisms can respond to changes in their environment (stimuli), such as plants bending toward light or animals moving away from danger. The other options are not true for all life.
2. What does the cell theory state about the origin of cells?
Cell theory includes the idea that new cells are produced by division of existing cells, not by spontaneous generation or other processes listed.
3. Which organelle is known as the 'powerhouse' of the cell because it produces energy?
Mitochondria produce ATP through cellular respiration, supplying energy for cell activities. Chloroplasts produce energy in plants via photosynthesis but are not called the powerhouse in general.
4. Which cell structure controls what enters and leaves the cell?
The cell membrane is selectively permeable and regulates the movement of substances into and out of the cell. The cell wall is rigid and found in plants and bacteria but does not control movement selectively.
5. Which of these is a prokaryotic organism?
Bacteria are prokaryotic (no true nucleus or membrane-bound organelles). Amoeba, human cells, and plant cells are eukaryotic.
6. What is biodiversity?
Biodiversity refers to the variety and variability of life forms in a particular habitat, ecosystem, or the whole Earth.
7. Which of the following best describes an ecosystem?
An ecosystem includes both biotic (living) and abiotic (non-living) components and the interactions among them.
8. Which level of biological organisation comes directly after cell?
Cells with similar structure and function form tissues; tissues combine to make organs, then organ systems, and finally organisms and populations.
9. Which process describes movement of water across a selectively permeable membrane from high to low concentration?
Osmosis is the passive movement of water molecules across a selectively permeable membrane from a region of higher water concentration to lower water concentration.
10. Which kingdom includes multicellular photosynthetic organisms with cell walls made of cellulose?
Plants (Kingdom Plantae) are multicellular, perform photosynthesis and have cell walls made mainly of cellulose. Fungi have cell walls made of chitin and are not photosynthetic.
11. Why is genetic variation important for biodiversity?
Genetic variation provides different traits within a species, increasing the chances that some individuals can survive changes in the environment, supporting long-term survival.
12. Which organelle is present in plant cells but not animal cells and is the site of photosynthesis?
Chloroplasts contain chlorophyll and carry out photosynthesis in plant cells. Large central vacuoles are common in plants but chloroplasts specifically perform photosynthesis.
13. Which of the following is an example of a biotic factor in an ecosystem?
Biotic factors are living components, such as predators, competitors, and plants. Temperature, soil pH, and sunlight are abiotic (non-living) factors.
14. Which method is best for estimating the population of small plants in a grassland?
Quadrat sampling is a practical method to estimate numbers or density of small, common organisms by sampling representative areas and extrapolating to the whole site.
15. What is the main difference between autotrophs and heterotrophs?
Autotrophs (like plants) produce their own organic food (e.g., by photosynthesis), while heterotrophs obtain organic matter by feeding on other organisms.
16. Which of the following best defines a species?
A species is defined by reproductive compatibility and producing fertile offspring under natural conditions; habitat or diet alone do not define a species.
17. Why are wetlands important for biodiversity in Kenya?
Wetlands provide habitat for diverse species, filter pollutants from water, recharge groundwater and help control floods, making them valuable for biodiversity and human communities.
18. Which structure contains the genetic material in a eukaryotic cell?
The nucleus houses the cell's DNA and controls cell activities in eukaryotic cells. Ribosomes make proteins, mitochondria produce energy, and the membrane controls transport.
19. What is natural selection?
Natural selection is the mechanism by which advantageous traits become more common in a population because those individuals are more likely to survive and reproduce.
20. Which device and adjustment would you use first to view a prepared microscope slide at low power?
Start with the low power objective and use the coarse focus to locate the specimen; finer adjustments and higher power can be used afterward.
21. Which process in cells converts glucose into usable energy (ATP) in the presence of oxygen?
Aerobic respiration breaks down glucose in the presence of oxygen to produce ATP. Photosynthesis makes glucose, fermentation is anaerobic, and transpiration is water loss from plants.
22. What is an adaptation?
An adaptation is a heritable trait that improves an organism's ability to survive and reproduce in its environment.
23. Which of the following is an example of a conservation action to protect biodiversity in Kenya?
Creating protected areas, restoring degraded habitats and enforcing conservation laws help preserve species and ecosystems. The other actions harm biodiversity.
24. Which statement is true about unicellular and multicellular organisms?
Multicellular organisms have many cells that differentiate into tissues and organs with specialized functions; unicellular organisms consist of a single cell.
25. Which factor would NOT directly affect the distribution of species in an area?
Factors like food, water, soil, predators and competitors directly influence species distribution; laboratory equipment size has no effect on wild species distribution.