Your science teacher has asked the class to make a cell city model. Which building or business in the city could represent the mitochondria and why?

• Power company - Produces energy

• City dump - Waste storage

• City hall - Control center

• Roads - Transportation system

Answer explanation

The mitochondria are known as the powerhouse of the cell because they produce energy in the form of ATP. Similarly, a power company generates energy for the city, making it the best representation of mitochondria.

Tags

NGSS.MS-LS1-2

An analysis of a plant cell would show which ability that an animal cell would lack? What organelle would be involved in this process?

• The plant cell can perform cell division, which occurs when the nucleus and the cell membrane divide

• The plant cell can perform protein production, which occur in the nucleus

• The plant cell can produce glucose (food) from light energy, which occurs in the chloroplast

• The plant cell can perform cellular respiration, which occurs in the cell wall.

Answer explanation

The correct choice highlights that plant cells can produce glucose from light energy through photosynthesis, a process that occurs in chloroplasts, which animal cells lack.

Tags

NGSS.MS-LS1-2

NGSS.MS-LS1-6

A student is shown an unlabeled, simplified model of a cell and its subcellular structures. The student is asked to adjust the model to show a cell that can meet high energy demands. Which statement BEST addresses this task?

• The student should increase the amount of structure 10 to increase the size of the cell.

• The student should increase the number of structure 3, because it is responsible for generating energy in the cell.

• The student should decrease the size of structure 1 to decrease the genetic material.

• The student should increase the amount of structure 4, because it is responsible for manufacturing proteins.

Answer explanation

Increasing the number of structure 3 is essential because it likely represents mitochondria, which generate ATP, the energy currency of the cell. More mitochondria enable the cell to meet high energy demands effectively.

Tags

NGSS.MS-LS1-2

NGSS.MS-LS1-7

The cell membrane forms a protective barrier between the external and internal environments. It is referred to as because it allows some substances to cross more easily than others and blocks other substances from crossing into the cell.

• Selectively permeable

• Lockable

• Sticky

• Fluid

Answer explanation

The cell membrane is described as selectively permeable because it allows certain substances to pass through while blocking others, thus maintaining the internal environment of the cell.

Which of the following would form first during the development of a complex multicellular organism, such as an animal?

• Tissue

• Cell

• Organ system

• Organ

Answer explanation

During the development of a complex multicellular organism, the first unit to form is the cell. Cells combine to create tissues, which then form organs and organ systems, making 'cell' the correct answer.

Tags

NGSS.MS-LS1-1

NGSS.MS-LS1-3

Which answer correctly depicts the levels of organization needed to form a plant?

• cell → tissue → organ (leaf) → plant

• tissue → organ (leaf) → cell → tissue → plant

• tissue → cell → organ (leaf) → plant

• plant → cell → tissue → organ (leaf)

Answer explanation

The correct order of organization in plants is from the smallest unit, the cell, to tissues, then to organs like leaves, and finally to the whole plant. Thus, 'cell → tissue → organ (leaf) → plant' accurately represents this hierarchy.

Tags

NGSS.MS-LS1-1

NGSS.MS-LS1-2

Which statement correctly describes a level of organization in the human nervous system?

• A. Nerve cells group to form nerve tissue

• B. The brain is a group of nervous systems

• C. The nervous system has two groups of nerve tissues

• D. The organs of the nervous system form a nerve cell

Answer explanation

Choice A is correct because nerve cells, or neurons, group together to form nerve tissue, which is a fundamental level of organization in the nervous system. The other options misrepresent the structure of the nervous system.

Tags

NGSS.MS-LS1-3

Most living things need oxygen to survive. These two body systems bring oxygen into your body and then move to all your body parts. What are these two body systems?

• Digestive & circulatory

• Respiratory & muscular

• Circulatory & respiratory

• Respiratory & digestive

Answer explanation

The circulatory and respiratory systems work together to bring oxygen into the body and distribute it to all body parts. The respiratory system takes in oxygen, while the circulatory system transports it throughout the body.

Which system would be responsible for moving bones in the body so you can wave to a friend?

• Excretory

• Circulatory

• Digestive

• Muscular

Answer explanation

The muscular system is responsible for moving bones and enabling actions like waving. Muscles contract to pull on bones, allowing for movement, while the other systems listed (excretory, circulatory, digestive) do not directly facilitate movement.

What would happen without excretory systems in humans?

• Blood would not circulate through the body

• Nutrients would not be absorbed

• Wastes would build up in blood and damage the body

• Oxygen would not enter the bloodstream

Answer explanation

Without excretory systems, waste products would accumulate in the blood, leading to toxicity and potential damage to organs. This makes the correct answer 'Wastes would build up in blood and damage the body'.