Question 1 of 10
Which structure is found in plant cells but NOT in animal cells?
ACell wall
BRibosomes
CCell membrane
DMitochondria
Explanation
📌 Plant cells have: cell wall, chloroplasts, large central vacuole.
Animal cells do NOT have these.
Animal cells do NOT have these.
Question 2 of 10
A scientist measures the growth of bacteria at different temperatures. The temperature is the:
Adependent variable
Bindependent variable
Ccontrol variable
Dconstant
Explanation
📌 Temperature is what the scientist controls/changes → independent variable.
Bacteria growth is what is measured → dependent variable.
Bacteria growth is what is measured → dependent variable.
Question 3 of 10
Which of the following is the BEST example of a hypothesis?
APhotosynthesis is a very important process for living things on Earth
BPlants need water
CIf plants receive more sunlight, then they will grow taller
DEvery single plant that exists is green in color without any exception
Explanation
📌 A hypothesis is a testable, specific prediction.
The if-then statement about sunlight and plant height is testable and specific. A simple need statement, a broad value judgment, or a sweeping generalization cannot be tested the same way.
The if-then statement about sunlight and plant height is testable and specific. A simple need statement, a broad value judgment, or a sweeping generalization cannot be tested the same way.
Question 4 of 10
The DNA double helix is shown. Which base pairs are correctly bonded?
AA pairs with G, and T pairs with C
BA pairs with C, and T pairs with G
CA pairs with T, and G pairs with C
DAll bases pair with each other freely
Explanation
In DNA, complementary base pairing is strict: Adenine (A) – Thymine (T) via 2 hydrogen bonds; Guanine (G) – Cytosine (C) via 3 hydrogen bonds.
Question 5 of 10
Which organelle is labeled X in the cell diagram below?
ANucleus
BEndoplasmic reticulum
CMitochondria
DGolgi apparatus
Explanation
📌 Organelle X has the bean-shaped structure with inner folds (cristae) → Mitochondria
Mitochondria = powerhouse of the cell = produces ATP through cellular respiration
C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + ATP
Mitochondria = powerhouse of the cell = produces ATP through cellular respiration
C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + ATP
Question 6 of 10
Which organelle is responsible for producing energy (ATP) in the cell?
ANucleus
BMitochondria
CRibosome
DGolgi apparatus
Explanation
📌 Mitochondria = 'powerhouse of the cell'
They convert glucose + oxygen → ATP through cellular respiration.
They convert glucose + oxygen → ATP through cellular respiration.
Question 7 of 10
Which graph correctly shows exponential growth?
AB
BNeither
CBoth
DA
Explanation
📌 Exponential growth = J-shaped curve (slow start, rapid increase)
Linear growth = straight line (constant rate)
Graph A shows exponential growth.
Linear growth = straight line (constant rate)
Graph A shows exponential growth.
Question 8 of 10
In a controlled experiment, what is the independent variable?
AThe control group
BThe variable that stays constant
CThe variable that is deliberately changed
DThe variable that is measured
Explanation
📌 The independent variable is what the scientist deliberately changes/manipulates.
The dependent variable is what is measured as a result.
The dependent variable is what is measured as a result.
Question 9 of 10
What is the function of the cell membrane?
AStores all of the cell's genetic information and DNA
BControls what enters and exits the cell
CBuilds and assembles all of the cell's various proteins
DProduces the energy that the entire cell needs to survive
Explanation
📌 The cell membrane is selectively permeable — it controls what enters and exits the cell.
It is made of a phospholipid bilayer. Storing genetic information is the nucleus's job, producing energy is the mitochondrion's, and building proteins is done by ribosomes.
It is made of a phospholipid bilayer. Storing genetic information is the nucleus's job, producing energy is the mitochondrion's, and building proteins is done by ribosomes.
Question 10 of 10
Which tool would be MOST appropriate for measuring the volume of a liquid?
AGraduated cylinder
BThermometer
CBalance
DRuler
Explanation
📌 A graduated cylinder is specifically designed for precise liquid volume measurement.
Beakers and flasks are for mixing, not precise measurement.
Beakers and flasks are for mixing, not precise measurement.