Under the Microscope: Lesson 3

What is the function of the cell membrane?

• A) It controls which substances can enter or exit the cell

• B) It carries out specific functions inside the cell

• C) It surrounds plant cells and gives them strength and structure

• D) It contains chlorophyll and carries out photosynthesis

Answer explanation

The cell membrane, also known as the plasma membrane, functions as a barrier, controlling the movement of substances in and out of the cell. This is crucial for maintaining the cell's internal environment. Therefore, the correct answer to the question is that the cell membrane controls which substances can enter or exit the cell.

Tags

NGSS.MS-LS1-2

What is a cell organelle?

• A) A structure inside of a plant or animal cell that carries out a specific function

• B) A wall containing the sugar cellulose that surrounds plant cells

• C) A tiny part in a plant containing chlorophyll

• D) A jelly-like substance where chemical reactions occur

Answer explanation

A cell organelle is a structure inside of a plant or animal cell that carries out a specific function. This is the correct answer because cell organelles are specialized structures within the cell that perform specific tasks, contributing to the overall function of the cell. Other options refer to different parts or characteristics of a cell, but not specifically to an organelle.

Tags

NGSS.MS-LS1-2

What is the function of the cell wall?

• A) It controls which substances can enter or exit the cell

• B) It carries out specific functions inside the cell

• C) It surrounds plant cells and gives them strength and structure

• D) It contains chlorophyll and carries out photosynthesis

Answer explanation

The cell wall, found in plant cells, provides strength and structure. It is a rigid layer that surrounds the cells, giving them the necessary support and balance. This is why the correct answer to the question is 'It surrounds plant cells and gives them strength and structure'.

Tags

NGSS.MS-LS1-2

Where does photosynthesis occur in a plant cell?

• A) Cell membrane

• B) Cell organelle

• C) Cell wall

• D) Chloroplast

Answer explanation

Photosynthesis occurs in the chloroplast of a plant cell. This is where the plant converts light energy into chemical energy. The chloroplast contains chlorophyll, a green pigment that absorbs light and uses its energy to synthesise carbohydrates from CO2 and water. This process is known as photosynthesis. Therefore, the correct answer is 'Chloroplast'.

Tags

NGSS.MS-LS1-6

What is cytoplasm?

• A) It controls which substances can enter or exit the cell

• B) It carries out specific functions inside the cell

• C) It surrounds plant cells and gives them strength and structure

• D) It is a jelly-like substance where chemical reactions occur

Answer explanation

Cytoplasm is a jelly-like substance found within cells, where various chemical reactions take place. It is not responsible for controlling substance entry or exit, carrying out specific functions, or providing strength and structure to plant cells. The correct choice highlights the role of cytoplasm in facilitating chemical reactions.

Tags

NGSS.MS-LS1-2

What is the function of mitochondria?

• A) It breaks down food to release energy to the cell through a process called cellular respiration

• B) It carries out photosynthesis

• C) It surrounds plant cells and gives them strength and structure

• D) It contains genetic material and controls cell functions

Answer explanation

Mitochondria are known as the powerhouse of the cell because they break down food to release energy through a process called cellular respiration. This energy is essential for various cellular functions. The other options, such as photosynthesis, providing strength and structure to plant cells, and containing genetic material, are not the primary functions of mitochondria.

Tags

NGSS.MS-LS1-2

What is a mutation?

• A) It controls which substances can enter or exit the cell

• B) It carries out specific functions inside the cell

• C) It is an organelle found inside cells that breaks down food

• D) It is a change in a gene that can cause positive or negative effects

Answer explanation

A mutation refers to a change in a gene that can lead to various effects, both positive and negative. The other options describe different cellular components and functions, such as controlling substance movement, carrying out specific functions, and breaking down food, which are not related to mutations.

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NGSS.MS-LS3-1

What is the function of the nucleus?

• A) It controls which substances can enter or exit the cell

• B) It carries out specific functions inside the cell

• C) It contains genetic material and controls cell functions

• D) It is a jelly-like substance where chemical reactions occur

Answer explanation

The nucleus is the control center of the cell, containing genetic material (DNA) that determines the cell's characteristics and functions. It regulates gene expression and controls cell growth, reproduction, and differentiation. The other options describe functions of other cell components, such as the cell membrane, organelles, and cytoplasm.

Tags

NGSS.MS-LS1-2

What is photosynthesis?

• A) It controls which substances can enter or exit the cell

• B) It carries out specific functions inside the cell

• C) It is a process by which plant cells use light to convert carbon dioxide and water into sugar

• D) It is a change in a gene that can cause positive or negative effects

Answer explanation

Photosynthesis is a process by which plant cells use light to convert carbon dioxide and water into sugar. This process is essential for plants to produce energy and grow. The correct choice highlights this process, which is distinct from controlling substances entering or exiting the cell, carrying out specific functions inside the cell, or changes in a gene causing positive or negative effects.

Tags

NGSS.MS-LS1-6

NGSS.MS-LS2-3

What is a ribosome?

• A) It controls which substances can enter or exit the cell

• B) It carries out specific functions inside the cell

• C) It is a tiny round particle in a cell where proteins are made

• D) It is a closed sac found in plant cells that carries out various functions

Answer explanation

A ribosome is a tiny round particle in a cell where proteins are made. It is not responsible for controlling substances entering or exiting the cell, nor does it carry out specific functions inside the cell. Additionally, it is not a closed sac found in plant cells. Its primary function is protein synthesis, making it an essential component of all living cells.

Tags

NGSS.MS-LS1-2