Nature of Science
This variable is the one a scientist changes on purpose in an experiment.
What is the independent variable?
This part of the microscope is where you look through to see the specimen.
What is the eyepiece (ocular lens)?
The organelles that perform photosynthesis in plant cells.
What are chloroplasts?
The primary energy molecule made during cellular respiration.
What is ATP?
Sweating when you’re hot and shivering when you’re cold are examples of this type of feedback loop.
What is a negative feedback loop?
In CER, this is the scientific data that supports the claim.
What is evidence?
All living things share these seven traits (name at least 3).
What are cells, use energy, respond to environment, grow/develop, reproduce, maintain homeostasis?, and adapt?
The cell membrane helps maintain this by controlling what enters and leaves the cell.
What is homeostasis?
These three stages that make up photosynthesis.
What are the light reactions (independent and dependent) and the Calvin cycle?
These structures inside chloroplasts contain chlorophyll and are the site of the light reactions.
What are the thylakoids?
This is the safe method for identifying the smell of a chemical during a lab investigation.
What is wafting?
A cactus closes its stomata during the hottest part of the day to prevent water loss and opens them at night to take in carbon dioxide.
Which characteristic of life is the cactus demonstrating?
Response to the environment (the cactus is reacting to changes in temperature and water availability to survive)
In this type of solution, water moves into the cell, causing it to swell.
What is a hypotonic solution?
This process occurs in the cytoplasm and breaks glucose into two pyruvate molecules.
What is glycolysis?
In cellular respiration, these two molecules carry electrons to the electron transport chain.
What are NADH and FADH₂?
This is why scientific laws and theories cannot become one another.
What is they answer different questions (laws describe what happens; theories explain why)?
This explains why electron microscopes cannot observe living organisms.
What is they use beams of electrons, requiring specimens to be dead and placed in a vacuum?
Name all three parts of cell theory.
What are all living things are made of cells, cells are the basic unit of life, all cells come from preexisting cells?
This is why aerobic respiration produces much more ATP than fermentation.
What is oxygen allows the electron transport chain to produce large amounts of ATP?
When muscles run out of oxygen, this type of fermentation occurs.
What is lactic acid fermentation?
A student wants to test how the type of soil affects the height of sunflower plants. They use three soil types (sand, clay, potting mix) and give each plant the same amount of water, sunlight, and fertilizer. After four weeks, they measure plant height.
In this experiment, identify the independent variable, dependent variable, and two controls.
Independent variable: Type of soil
Dependent variable: Height of the sunflower plants
Controls: Amount of water, amount of sunlight, fertilizer, same plant species, same pot size (any two accepted)
A student is examining a specimen under a compound microscope. The microscope has three objective lenses:
Low power: 5×
Medium power: 12×
High power: 45×
The eyepiece lens has a magnification of 12×.
If the student uses the medium power objective lens, what is the total magnification, and how would the field of view compare to low power?
Step 1: Calculate total magnification
Total Magnification=Eyepiece Magnification × Objective Magnification =12×12=144×
Step 2: Compare field of view to low power
Low power (5× objective × 12× eyepiece = 60×) has a wider field of view.
Medium power (144×) has a narrower field of view but more detail.
Answer:
Total magnification: 144×
Field of view compared to low power: Smaller and more zoomed in; you see less area but more detail.
A student is comparing two cells under a microscope. One cell has a large central vacuole and a rigid cell wall, while the other has small vacuoles and no cell wall.
Which cell is a plant cell and which is an animal cell? Explain the function of the vacuole in each.
Plant cell: The cell with a large central vacuole and cell wall. The vacuole stores water and nutrients and helps maintain turgor pressure to keep the plant rigid.
Animal cell: The cell with small vacuoles and no cell wall. The vacuoles store small amounts of materials and help with waste removal, but do not provide structural support.
A student places two identical plants under different conditions. Plant A is in bright sunlight, and Plant B is kept in a dark closet. After a week, the student measures the oxygen production and glucose levels in both plants.
Explain which plant produces more glucose and oxygen, why this happens, and what process is occurring in each plant.
Plant A (sunlight): Produces more glucose and oxygen because it is performing photosynthesis, using light energy to convert carbon dioxide and water into glucose and oxygen.
Plant B (dark): Produces little to no glucose or oxygen from photosynthesis. It still performs cellular respiration, breaking down stored glucose to make ATP, but cannot make new glucose without light.
During a severe bacterial infection, certain immune cells release cytokines to fight the infection. These cytokines stimulate more immune cells to release even more cytokines. In extreme cases, this leads to a cytokine storm, where the body’s immune response escalates rapidly.
Identify the type of feedback loop, explain why it is, and describe the potential risk if it continues unchecked.
Type of feedback loop: Positive feedback loop
Explanation: It is positive because the response amplifies the original stimulus—cytokines trigger more cytokine release, increasing the immune response.
Potential risk: If uncontrolled, the cytokine storm can damage healthy tissues and organs, potentially leading to severe illness or death.