staar review

Front

What is the function of nucleic acids?

Back

Store and transmits genetic information

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.

Front

Which biomolecule is properly matched to its monomer?

Back

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.

Front

How did the enzyme affect the reaction in the graph where Line B represents the reaction with an enzyme added to the substrates?

Back

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.

Front

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?

Back

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.

Front

Function of the cell membrane in all cells? Options: Producing cellular nutrients, Maintaining homeostasis, Neutralizing chemicals, Preserving cellular wastes

Back

Maintaining homeostasis

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.

Front

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

Back

water was 90% inside the cell and 95% 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.

Front

What happens during the S phase of interphase in the cell cycle?

Back

DNA replicates.

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.

Front

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

Back

Vestigial structure

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.

Front

Structures that indicate shared ancestry; look similar anatomically

Back

Homologous structure

Answer explanation

Homologous structures are anatomical features that share a common ancestry, indicating evolutionary relationships. They may serve different functions but retain similar forms, unlike analogous structures, which arise from convergent evolution.

Front

Structures that do not indicate shared ancestry; structures do same functions

Back

Analagous structure

Answer explanation

Analagous structures perform similar functions but do not share a common ancestry, unlike homologous structures which do. This makes 'analagous structure' the correct choice for the question.