Unit 2 Test Review

Which cell type is single-celled?

• prokaryotic

• eukaryotic

Answer explanation

Prokaryotic cells are single-celled organisms that lack a nucleus and other complex organelles, unlike eukaryotic cells. Therefore, the correct answer to the question 'Which cell type is single-celled?' is 'prokaryotic'.

Which cell type has organelles?

• prokaryotic

• eukaryotic

Answer explanation

The question asks about the type of cell that has organelles. Eukaryotic cells are the correct answer because they contain organelles such as the nucleus, mitochondria, and endoplasmic reticulum. On the other hand, prokaryotic cells do not have these organelles.

Select all that applies to bacteria

• maintain homeostasis

• has ribosomes

• reproduce

• has nuclear membrane

Answer explanation

Bacteria, being a type of prokaryotic organism, do not have a nuclear membrane. However, they do maintain homeostasis, have ribosomes for protein synthesis, and are capable of reproduction. These characteristics are essential for their survival and proliferation.

Tags

NGSS.MS-LS1-2

NGSS.MS-LS1-5

NGSS.MS-LS3-1

Which biomolecule is DNA an example of?

• Nucleic Acid

• Lipids

• Protien

• Carbohydrates

Answer explanation

DNA is an example of a nucleic acid. Nucleic acids are biomolecules essential to all forms of life, and include DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). These molecules are involved in the storage and reading of genetic information. Therefore, the correct answer to the question is 'Nucleic Acid'.

T of F: both prokaryotes and eukaryotes have DNA

• true

• false

Answer explanation

The statement in the question is true. Both prokaryotes and eukaryotes have DNA. DNA is the genetic material that carries information about an organism. It is found in every living thing, regardless of whether it is a prokaryote (like bacteria) or a eukaryote (like plants, animals, and humans).

Which cell type performs photosynthesis?

• bacteria

• prokaryote

• eukaryote

• virus

Answer explanation

The correct answer is eukaryote. Eukaryotes are a type of cell that have a nucleus and other organelles enclosed within membranes. Photosynthesis, the process by which green plants and some other organisms use sunlight to synthesize foods with the aid of chlorophyll, is primarily performed by eukaryotic cells, specifically those of plants and algae.

Tags

NGSS.MS-LS1-6

T or F: plant cells have cell walls

• True

• False

Answer explanation

The statement in the question is true. Plant cells do indeed have cell walls. This is a key characteristic that differentiates them from animal cells. The cell wall provides structural support and protection to the plant cell.

T or F: bacteria cells have cell walls

• True

• False

Answer explanation

The statement in the question is true. Bacteria cells do indeed have cell walls. The cell wall is a crucial component of the bacterial cell, providing structural support and protection. It is made up of peptidoglycan, a polymer consisting of sugars and amino acids. This structure allows bacteria to survive in a variety of environments and withstand different types of stress.

T or F: passive transport requires energy and moves against concentration gradient

• True

• False

Answer explanation

The statement in the question is false. Passive transport does not require energy as it moves substances from an area of higher concentration to an area of lower concentration, following the concentration gradient. It does not move against the concentration gradient.

What do vesicles do?

• exchange genes

• extract portions of golgi

• transport molecules

Answer explanation

Vesicles are small, membrane-bound sacs that function to transport molecules within cells. They play a crucial role in moving substances between different cellular compartments, such as the endoplasmic reticulum, Golgi apparatus, and plasma membrane. Therefore, the correct choice is that vesicles transport molecules, rather than exchanging genes or extracting portions of the Golgi.