Cellular Structure, Function and Transport — Test Review

Studying a picture of a cell taken with an electron microscope, you find that the cell has no nucleus and no mitochondria, but it does have a plasma membrane and a cell wall. You conclude that the cell is probably from a(n). (2pts)

• plant

• animal

• bacteria

• extinct organism

Answer explanation

The absence of a nucleus and mitochondria, along with the presence of a plasma membrane and cell wall, indicates that the cell is prokaryotic. This is characteristic of bacteria, which lack membrane-bound organelles.

Which of the following organelles would you expect to find in plant cells but not animal cells? (1pt)

• ribosome

• chloroplast

• mitochondria

• endoplasmic reticulum

Answer explanation

Chloroplasts are organelles found in plant cells that enable photosynthesis, a process not present in animal cells. Ribosomes, mitochondria, and endoplasmic reticulum are found in both cell types.

Which of the following is NOT a principle of the cell theory? (1pt)

• All living things are made of cells.

• Cells are the basic units of life.

• Very few cells are able to reproduce.

• All cells are produced from existing cells.

Answer explanation

The statement 'Very few cells are able to reproduce' is incorrect. In fact, most cells can reproduce, which is a fundamental aspect of life. The other options accurately reflect the principles of cell theory.

Tags

NGSS.MS-LS1-1

A particularly active cell, such as a muscle cell, might contain large numbers of. (2pts)

• vacuoles

• lysosomes

• mitochondria

• chromosomes

Answer explanation

Muscle cells require a lot of energy to function, which is produced by mitochondria. Therefore, active cells like muscle cells contain large numbers of mitochondria to meet their high energy demands.

Tags

NGSS.MS-LS1-2

A cell membrane is composed of a double layer of lipids in which many kinds of proteins are embedded. Many of these proteins act like gates, allowing only certain particles to enter or leave the cell. When a particle has to go against its concentration gradient through one of these gates, energy is supplied by the cell to the correct protein to move the particle through the membrane. A sodium-potassium ion pump is an example of a type of carrier protein that used a large portion of the cell's energy to move sodium ions through the cell membrane. Which of the following best describes the type of cellular transport in the picture above? (3pts)

• Active transport, it requires energy and moves from high to low concentration.

• Active transport, it requires energy and moves from low to high concentration.

• Passive transport, it does not require energy and moves from high to low concentration.

• Passive transport, it does not require energy and moves from low to high concentration.

Answer explanation

The correct choice is 'Active transport, it requires energy and moves from low to high concentration.' This is because the sodium-potassium pump uses energy to move sodium ions against their concentration gradient.

Tags

NGSS.MS-LS1-2

The organelle that breaks down lipids, carbohydrates, and proteins into small molecules that can be used by the cell are called. (1pt)

• vacuoles

• ribosomes

• lysosomes

• mitochondria

Answer explanation

Lysosomes are organelles that contain enzymes to break down lipids, carbohydrates, and proteins into smaller molecules, making them essential for cellular digestion and recycling.

Tags

NGSS.MS-LS1-7

An animal cell that is surrounded by fresh water will burst because the osmotic pressure causes. (1pt)

• water to move into the cell.

• water to move out of the cell.

• solutes to move into the cell.

• solutes to move out of the cell.

Answer explanation

An animal cell in fresh water experiences higher osmotic pressure outside than inside, causing water to move into the cell. This influx of water leads to swelling and eventually bursting of the cell.

Tags

NGSS.MS-LS1-1

Who used a compound light microscope to see chambers within cork and named them "cells"?

• Robert Hooke

• Anton von Leeuwenhoek

• Matthias Schleiden

• Rudolf Virchow

Answer explanation

Robert Hooke used a compound light microscope to examine cork and discovered small chambers, which he named "cells". This was a pivotal moment in biology, marking the first time cells were identified.

Which of the following best describes the relationship between the nucleus and the cytoplasm? (2pts)

• The cytoplasm is a fluid that fills the inside of the nucleus.

• The nucleus is a fluid and it mixes with the fluid cytoplasm.

• The nucleus is an organelle that is surrounded by the cytoplasm.

• The cytoplasm is an organelle that is usually found near the nucleus.

Answer explanation

The nucleus is an organelle that contains genetic material and is surrounded by the cytoplasm, which is the fluid that fills the cell. This choice accurately describes their relationship.

Which structure in the cell shown in Figure 7-2 below stores materials, such as water, salts, proteins, and carbohydrates? (2pts)

• Structure A

• Structure B

• Structure C

• Structure D

Answer explanation

Structure C is the correct answer as it represents the vacuole, which is responsible for storing materials like water, salts, proteins, and carbohydrates in the cell.

Tags

NGSS.MS-LS1-2

NGSS.MS-LS1-1