9th Grade Biology Quiz
Questions: 16 · 10 minutes
1. Which statement best describes the relationship between a gene and DNA?
A gene is a protein that stores DNA in the nucleus
A gene is a segment of DNA containing instructions for a functional product
A gene is a sugar used to build the DNA backbone
A gene is an entire set of chromosomes from an organism
2. A persistent pesticide enters this food chain: grass → grasshopper → frog → hawk. If the chemical becomes more concentrated at each trophic level, which organism will probably have the highest concentration?
Hawk
Grasshopper
Grass
Frog
3. An enzyme works well at 37°C but stops functioning after being heated to 90°C. What is the best explanation?
The enzyme changed into a carbohydrate
The reaction permanently used up the enzyme
The heat altered the enzyme’s shape, including its active site
The heat converted the enzyme into additional substrate
4. Why is less usable energy available to organisms at higher levels of a food chain?
Producers absorb all energy again before consumers can use it
Energy is destroyed whenever one organism eats another
Organisms use energy for life processes and release much of it as heat
Consumers store all absorbed energy permanently in their cells
5. Which pair of substances is used as the main reactants in aerobic cellular respiration?
Carbon dioxide and water
Glucose and oxygen
ATP and carbon dioxide
Oxygen and water
6. During exercise, a person’s body temperature rises and sweating increases. How does sweating help maintain homeostasis?
Evaporation converts heat into stored glucose
Sweat causes cells to produce more heat
Sweat permanently lowers the body’s normal temperature setting
Evaporation of sweat removes heat from the body
7. In pea plants, tallness (T) is dominant to shortness (t). If a Tt plant is crossed with a tt plant, what percentage of the offspring is expected to be tall?
25%
0%
50%
100%
8. A drop of food coloring is placed in water and gradually spreads without stirring. Which process best explains this movement?
Osmosis, because only water molecules move
Endocytosis, because the water encloses the dye
Active transport, because cellular energy moves the dye
Diffusion, because particles move from higher to lower concentration
9. A healthy green plant is moved from bright light into complete darkness. Which activity will directly decrease because light is no longer available?
The breakdown of glucose during cellular respiration
The production of oxygen during photosynthesis
The movement of water through cell membranes
The copying of DNA before cell division
10. A student switches a microscope from a low-power objective to a high-power objective. What will usually happen to the field of view?
It will show a smaller area of the specimen
It will show a larger area of the specimen
It will show the entire slide at once
It will remain the same size while only the color changes
11. Which organelle produces most of a eukaryotic cell’s usable ATP during cellular respiration?
Lysosome
Nucleus
Golgi apparatus
Mitochondrion
12. Which type of cell division allows a cut in the skin to heal by producing genetically similar replacement cells?
Meiosis
Mitosis
Fertilization
Mutation
13. Scientists compare DNA sequences from four species. Species A and B have the most similar sequences. What is the best-supported inference?
Species A evolved directly into Species B during its lifetime
Species A and B must live in identical habitats
Species A and B must have exactly the same visible traits
Species A and B likely share a more recent common ancestor with each other
14. A few insects in a population have an inherited trait that helps them survive a pesticide. After repeated pesticide use, the trait becomes more common. Which process best explains this change?
Natural selection favored insects with the inherited resistance trait
The insects intentionally changed their genes when exposed
Every insect developed the same mutation because it needed protection
The pesticide caused resistant insects to stop reproducing
15. A student has an illness caused by a virus. Why would an antibiotic generally not eliminate the virus?
Viruses lack the bacterial structures and processes targeted by antibiotics
Viruses are too large for antibiotics to enter
Viruses have cell walls that block every antibiotic
Antibiotics only increase body temperature
16. Potato cells contain more dissolved solutes than the distilled water surrounding them. What will most likely happen to the potato pieces after several hours?
They will lose mass because solutes leave by active transport
They will lose mass because water enters the cells by diffusion
They will gain mass because water enters the cells by osmosis
Their mass will stay unchanged because distilled water has no particles