Biomolecules
A student tests four food samples using brown paper. One sample leaves an oil spot after drying.
Which biomolecule is present in that sample?
A. Carbohydrate
B. Lipid
C. Protein
D. Nucleic acid
B. Lipid
Which of the following is not a factor that affects photosynthesis?
A. Temperature
B. Water availability
C. Color of availabile light
D. Number of mitochondria in cells
D. Number of mitochondria in cells
How are photosynthesis and cellular respiration connected in the carbon cycle?
A. Respiration makes sunlight energy for photosynthesis.
B. Photosynthesis and respiration both absorb oxygen and release carbon dioxide.
C. Photosynthesis uses carbon dioxide to make glucose; respiration releases carbon dioxide by breaking it down.
D. Photosynthesis and respiration are unrelated processes.
C. Photosynthesis uses carbon dioxide to make glucose; respiration releases carbon dioxide by breaking it down.
A cell uses energy to move sodium ions out and potassium ions in. Which process is this an example of?
A. Osmosis
B. Diffusion
C. Active transport
D. Facilitated diffusion
C. Active transport
A red blood cell is placed in a hypertonic salt solution. What will happen to the cell and why?
A. It will shrink because water leaves the cell to balance solute concentrations.
B. It will swell because water enters the cell.
C. It will stay the same size because water moves equally in both directions.
D. It will absorb salt and burst.
A. It will shrink because water leaves the cell to balance solute concentrations.
Jamal lifts weights every day to build muscle. Which biomolecule helps repair and build his muscle tissue?
A. Protein
B. Carbohydrate
C. Lipid
D. Nucleic acid
A. Protein
Scientists are engineering bacteria to carry out photosynthesis like plants.
Which cellular structure would they need to add for this to work?
A. Chloroplasts to capture sunlight and make glucose
B. Mitochondria to break down water
C. Ribosomes to release oxygen
D. Vacuoles to absorb sunlight
A. Chloroplasts to capture sunlight and make glucose
Students place a small animal in a closed container with a plant and measure gas levels over time.
Why do oxygen and carbon dioxide levels remain stable?
A. The plant produces oxygen during photosynthesis, and the animal uses it for respiration.
B. The animal and plant both produce oxygen.
C. Both use only carbon dioxide.
D. The plant and animal stop their gas exchange in darkness.
A. The plant produces oxygen during photosynthesis, and the animal uses it for respiration.
What would happen if all the carrier proteins for glucose were destroyed in a cell membrane?
A. Glucose could still diffuse easily
B. Glucose transport would stop
C. ATP production would increase
D. Osmosis would speed up
B. Glucose transport would stop
A patient with severe dehydration is mistakenly given a hypertonic saline solution instead of isotonic saline.
What effect might this have on their cells?
A. The cells will stay normal because hypertonic means “balanced.”
B. Water will enter the cells, causing them to swell.
C. Water will leave the cells, causing them to shrink and worsen dehydration.
D. The cells will gain both water and solutes equally.
C. Water will leave the cells, causing them to shrink and worsen dehydration.
A doctor explains that genes carry instructions for traits like hair color. These instructions are stored in what type of biomolecule?
A. Protein
B. Lipid
C. Nucleic acid
D. Carbohydrate
C. Nucleic acid
A student grows three plants and exposes them to different levels of carbon dioxide. The plant with the lowest CO₂ level grows the slowest.
Which statement best explains the results?
A. Plants grow faster with less carbon dioxide.
B. Carbon dioxide causes chlorophyll to break down.
C. Carbon dioxide is a reactant needed to form glucose in photosynthesis.
D. Carbon dioxide blocks sunlight absorption.
C. Carbon dioxide is a reactant needed to form glucose in photosynthesis.
The process of cellular respiration can be shown as:
Glucose + Oxygen → Carbon dioxide + Water + Energy (ATP)
What does this process do for cells?
A. It changes energy from glucose into a form the cell can use (ATP).
B. It makes glucose from light energy.
C. It stores oxygen for later use.
D. It changes ATP into glucose.
A. It changes energy from glucose into a form the cell can use (ATP).
A white blood cell engulfs a bacterium. What process is this?
A. Diffusion
B. Endocytosis
C. Exocytosis
D. Active osmosis
B. Endocytosis
Why is maintaining an isotonic environment around cells important for homeostasis?
A. It removes carbon dioxide from the cells.
B. It stops water movement completely.
C. It causes cells to store oxygen.
D. It keeps water moving evenly in and out, preventing cells from swelling or shrinking.
D. It keeps water moving evenly in and out, preventing cells from swelling or shrinking.
A lab test reveals that a substance contains carbon, hydrogen, and oxygen in a 1:2:1 ratio. Which property best supports classifying it as a carbohydrate?
A. It is insoluble in water
B. It stores genetic information
C. It provides quick energy for cells
D. It forms enzymes to speed reactions
C. It provides quick energy for cells
If photosynthesis in a forest suddenly stopped for one week, which change would most likely occur first?
A. An increase in atmospheric oxygen
B. An increase in sunlight reflection
C. A decrease in available glucose for plants and animals
D. An increase in plant growth
C. A decrease in available glucose for plants and animals
When a runner sprints very fast, their muscles do not get enough oxygen. The muscles start to burn because:
A. The cells use oxygen to make ATP faster.
B. The cells switch to anaerobic respiration, which makes energy without oxygen and produces lactic acid.
C. The muscles have too much oxygen stored.
D. The cells stop making ATP.
B. The cells switch to anaerobic respiration, which makes energy without oxygen and produces lactic acid.
A wilted plant regains its shape after being watered.
What process caused water to move back into its cells?
A. Osmosis — water moved from the soil (high concentration) into the plant cells (low concentration).
B. Active transport — ATP pushed water into the roots.
C. Diffusion — water moved out of the plant into the soil.
D. Endocytosis — the plant “swallowed” the water droplets.
A. Osmosis — water moved from the soil (high concentration) into the plant cells (low concentration).
A houseplant’s leaves droop after a few days without water. After watering, the leaves become firm again.
Which statement best explains this change?
A. Water entered the cells by osmosis, restoring turgor pressure.
B. Water left the cells because the soil was hypertonic.
C. The plant performed active transport to pull in water.
D. The plant used ATP to move salt into the roots.
A. Water entered the cells by osmosis, restoring turgor pressure.
A scientist burns samples of three foods: bread (carbohydrate), meat (protein), and butter (lipid). Each sample releases carbon dioxide and water vapor.
What does this observation suggest about all three types of food molecules?
A. They are made of completely different elements
B. They all contain only nitrogen and sulfur
C. They all lack hydrogen
D. They all contain carbon, hydrogen, and oxygen
D. They all contain carbon, hydrogen, and oxygen
A student measures the oxygen released from a plant under red light, then under green light. The plant releases more oxygen under red light.
What conclusion can be made from this data?
A. Green light is absorbed best for photosynthesis
B. Red light provides more usable energy for photosynthesis
C. Green light makes plants use more carbon dioxide
D. Red light slows down photosynthesis
*** Think back to our plant growth lab***
B. Red light provides more usable energy for photosynthesis
A plant is placed in a sealed container with no oxygen. After a few hours, its cellular respiration rate drops.
What best explains this result?
A. The mitochondria store oxygen for later use.
B. The plant uses light instead of oxygen to respire.
C. Water replaces oxygen in the mitochondria.
D. Oxygen is required for cellular respiration, and without it, energy production slows down.
D. Oxygen is required for cellular respiration, and without it, energy production slows down.
If a cell’s ATP production stopped, which type of transport would be affected first?
A. Facilitated diffusion, because it uses ATP for protein channels.
B. Diffusion, because it uses ATP to move particles.
C. Osmosis, because water needs energy to move.
D. Active transport, because it requires energy from ATP.
D. Active transport, because it requires energy from ATP.
During cold weather, salt is often spread on icy roads. If salt seeps into nearby soil, plants sometimes wilt.
What causes this?
A. The salt enters the plant, increasing water uptake.
B. The salty soil becomes hypertonic, drawing water out of plant roots.
C. The plant becomes hypotonic and gains water.
D. The salt blocks oxygen from entering the leaves.
B. The salty soil becomes hypertonic, drawing water out of plant roots.