Free HESI Biology Questions and Answers

Question 1

What is the primary function of the mitochondria in a cell?

Accepted Answer

Energy production

Answer

The primary function of the mitochondria in a cell is energy production. Often called the 'powerhouses' of the cell, mitochondria generate most of the chemical energy needed to power the cell's biochemical reactions. They achieve this through cellular respiration, converting nutrients into adenosine triphosphate (ATP), which is the main energy currency used by the cell for various functions.

Question 2

Which organ system is primarily responsible for transporting nutrients and oxygen?

Accepted Answer

Circulatory system

Answer

The circulatory system, composed of the heart, blood vessels, and blood, is specifically designed to transport essential substances throughout the body. Its primary role is to deliver oxygen and nutrients to all cells and remove metabolic waste products like carbon dioxide, ensuring proper cellular function.

Question 3

Which macromolecule is responsible for storing genetic information?

Accepted Answer

Nucleic acids

Answer

Nucleic acids, specifically DNA (deoxyribonucleic acid) and RNA (ribonucleic acid), are the macromolecules responsible for carrying genetic information. DNA stores the complete hereditary instructions for an organism's development and function, while RNA plays a crucial role in expressing these instructions to build proteins.

Question 4

What part of the cell regulates what enters and leaves the cell?

Accepted Answer

Cell membrane

Answer

The cell membrane, also known as the plasma membrane, acts as a selectively permeable barrier that encloses the cell's contents. Its critical function is to control which substances can enter and exit the cell, thereby maintaining the cell's internal environment and facilitating communication with its surroundings.

Question 5

Which organelle is responsible for protein synthesis?

Accepted Answer

Ribosome

Answer

Ribosomes are essential cellular organelles responsible for protein synthesis, a process also known as translation. They read the genetic code carried by messenger RNA (mRNA) and use this information to assemble amino acids into specific protein chains, which then fold into functional proteins.

HESI (ATI) Practice Test

HESI (ATI) Practice Test

Free HESI Biology Questions and Answers