Biology STAAR/EOC Quick Review

Nucleic acids are biolomolecuses. Which of the following is the function of nucleic acids?

• Serves as the primary structural unit of biological membranes.

• Serve as energy storage.

• Store and transmits genetic information

• Serve as biological catalysts

Answer explanation

Nucleic acids, such as DNA and RNA, are essential for storing and transmitting genetic information, which is crucial for inheritance and protein synthesis. The other options do not accurately describe the primary function of nucleic acids.

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

Which biomolecule is properly matched to its monomer?

• nucleic acid: amino acid

• polypeptide: 1 glycerol + 3 fatty acids

• lipid: nucleotide

• carbohydrate: monosaccharide

Answer explanation

The correct match is carbohydrate: monosaccharide, as monosaccharides are the monomers that make up carbohydrates. The other options incorrectly pair biomolecules with their respective monomers.

Line B in the graph represents the reaction with an enzyme added to the substrates.

How did the enzyme affect the reaction?

• Increased the activation energy

• Increase the energy change

• Lowered the energy change

• Lowered the activation energy

Answer explanation

The enzyme lowered the activation energy, making it easier for the reaction to occur. This is reflected in Line B of the graph, which shows a faster reaction rate with the enzyme present.

Tags

NGSS.MS-PS3-5

Melinda had two slides of unknown cells. She recorded her observation of one on the chart.

According to the information in the given chart, what type of cell is cell X?

• bacteria cell

• prokaryotic cell

• plant cell

• animal cell

Answer explanation

Cell X is identified as an animal cell because it lacks a cell wall and chloroplasts, which are characteristic of plant cells. Additionally, it exhibits features typical of eukaryotic cells, confirming it as an animal cell.

Tags

NGSS.MS-LS1-1

NGSS.MS-LS1-2

Which of these is a function of the cell membrane in all cells?

• Producing cellular nutrients

• Maintaining homeostasis

• Neutralizing chemicals

• Preserving cellular wastes

Answer explanation

The cell membrane regulates what enters and exits the cell, thus maintaining homeostasis. This function is essential for cellular stability and balance, unlike the other options which are not universal functions of the cell membrane.

Tags

NGSS.HS-LS1-3

The image below represents a cell with a semipermeable membrane. The process of osmosis would explain the net movement of water into a cell if the initial percentage of

• protein was 35% inside the cell and 30% outside the cell.

• water was 95% inside the cell and 90% outside the cell.

• water was 90% inside the cell and 95% outside the cell

• protein was 30% inside the cell and 35% outside the cell.

Answer explanation

Osmosis is the movement of water from an area of higher water concentration to an area of lower concentration. Since water is 90% inside the cell and 95% outside, water moves into the cell, making this the correct choice.

Tags

NGSS.MS-LS1-2

The simplicity of prokaryotic cell prevents them from

• growing and reproducing

• responding to their environment

• forming specialized tissues and organs

• moving through their environment

Answer explanation

The simplicity of prokaryotic cells limits their ability to form specialized tissues and organs, as they lack the complex structures and organization found in eukaryotic cells, which are necessary for such differentiation.

Which of the following is correct about the events of the cell cycle?

• Little happens during the G₁ and G₂ phases of the cell cycle.

• DNA replicates during the S phase of interphase.

• Mitosis is usually the longest phase of the cell cycle when the cell is growing.

• Interphase consists of G₁, S, G2 phase and mitosis

Answer explanation

DNA replication occurs specifically during the S phase of interphase, making this statement correct. The other options contain inaccuracies regarding the cell cycle phases.

Tags

NGSS.MS-LS1-2

A trait that makes an organism better suited for their environment.

• Analagous structure

• Homologous structure

• Vestigial structure

• Adaptation

Answer explanation

An adaptation is a trait that enhances an organism's ability to survive and reproduce in its environment. This distinguishes it from analogous, homologous, and vestigial structures, which do not specifically refer to environmental suitability.

Tags

NGSS.HS-LS4-2

NGSS.HS-LS4-4

A structure that is no longer used by an organism. Remnants of what ancestors had.

• Analagous structure

• Homologous structure

• Vestigial structure

• Adaptation

Answer explanation

A vestigial structure is a remnant of an organ or part that had a function in an ancestor but is no longer used by the current organism. This aligns with the definition provided in the question.

Tags

NGSS.MS-LS4-2