ATI TEAS 7 Biology Exam: 200 Comprehensive Practice
Questions with Correct Answers and Rationales Latest
Update.
Introduction
This practice exam is designed to help you master the biology content assessed on
the ATI TEAS 7. It includes 200 multiple-choice questions covering all major
biology topics: cell structure and function, macromolecules, DNA and protein
synthesis, cell division, genetics and inheritance, evolution, metabolism, and
microbiology. Each question is followed by the correct answer in bold and a
detailed rationale in italics to reinforce your understanding. Use this resource to
identify strengths and weaknesses, and to build confidence for test day.
1. Which organelle is responsible for producing ATP through cellular respiration?
A) Nucleus
B) Ribosome
C) Mitochondrion
D) Golgi apparatus
Answer: C Rationale: Mitochondria are the powerhouses of the cell, generating ATP
via aerobic respiration. The nucleus houses DNA, ribosomes synthesize proteins,
and the Golgi modifies and packages proteins.
2. What is the primary function of ribosomes?
A) Lipid synthesis
B) Protein synthesis
C) DNA replication
D) Detoxification
Answer: B Rationale: Ribosomes translate mRNA into polypeptide chains, making
them the site of protein synthesis. Lipids are synthesized in the smooth ER, DNA
replication occurs in the nucleus, and detoxification is a function of peroxisomes
and smooth ER.
3. Which of the following is a characteristic of both prokaryotic and eukaryotic cells?
A) Membrane-bound nucleus
,B) Mitochondria
C) Ribosomes
D) Endoplasmic reticulum
Answer: C Rationale: Ribosomes are found in all cell types because they are
essential for protein synthesis. Prokaryotes lack membrane-bound organelles such
as a nucleus, mitochondria, and ER.
4. During which phase of the cell cycle does DNA replication occur?
A) G1 phase
B) S phase
C) G2 phase
D) M phase
Answer: B Rationale: Synthesis (S) phase is when DNA is replicated. G1 is cell
growth, G2 is preparation for mitosis, and M phase is mitosis and cytokinesis.
5. A cell is placed in a hypertonic solution. What will happen to the cell?
A) It will swell and burst.
B) It will shrink due to water leaving the cell.
C) It will remain unchanged.
D) It will undergo active transport.
Answer: B Rationale: In a hypertonic solution, water moves out of the cell by
osmosis, causing the cell to shrink (crenate). Swelling occurs in hypotonic
solutions, and isotonic solutions cause no net movement.
6. Which of the following is the monomer of proteins?
A) Nucleotide
B) Monosaccharide
C) Amino acid
D) Fatty acid
Answer: C Rationale: Proteins are polymers made from amino acid monomers.
Nucleotides form nucleic acids, monosaccharides form carbohydrates, and fatty
acids form lipids.
7. What type of bond is formed between amino acids in a polypeptide chain?
A) Hydrogen bond
B) Ionic bond
C) Peptide bond
D) Disulfide bond
Answer: C Rationale: Peptide bonds are covalent bonds formed by dehydration
synthesis between the carboxyl group of one amino acid and the amino group of
,another. Hydrogen bonds contribute to secondary structure, and disulfide bonds
stabilize tertiary structure.
8. Which of the following correctly describes the function of the Golgi apparatus?
A) Digests worn-out organelles
B) Synthesizes ribosomal RNA
C) Modifies, sorts, and packages proteins
D) Produces ATP
Answer: C Rationale: The Golgi apparatus modifies proteins (e.g., adding
carbohydrates) and packages them into vesicles for transport. Lysosomes digest
waste, the nucleolus synthesizes rRNA, and mitochondria produce ATP.
9. In a DNA molecule, adenine (A) pairs with:
A) Guanine (G)
B) Cytosine (C)
C) Thymine (T)
D) Uracil (U)
Answer: C Rationale: In DNA, A pairs with T via two hydrogen bonds; G pairs with
C. Uracil replaces thymine in RNA.
10. Which organelle contains digestive enzymes that break down cellular debris?
A) Peroxisome
B) Lysosome
C) Vacuole
D) Ribosome
Answer: B Rationale: Lysosomes are membrane-bound vesicles containing
hydrolytic enzymes that digest waste, pathogens, and damaged organelles.
Peroxisomes break down fatty acids and detoxify hydrogen peroxide.
11. What is the product of transcription?
A) Protein
B) mRNA
C) DNA
D) ATP
Answer: B Rationale: Transcription is the process of copying a DNA sequence into
messenger RNA (mRNA). Translation then converts mRNA into a protein.
12. Which of the following is a function of the smooth endoplasmic reticulum?
A) Protein synthesis
B) Lipid synthesis and detoxification
C) ATP production
, D) Packaging of proteins
Answer: B Rationale: Smooth ER lacks ribosomes and is involved in lipid synthesis,
carbohydrate metabolism, and detoxification of drugs/poisons. Rough ER
synthesizes proteins, and the Golgi packages them.
13. A mutation that changes a single nucleotide but does not change the amino acid
specified is called:
A) Missense mutation
B) Nonsense mutation
C) Silent mutation
D) Frameshift mutation
Answer: C Rationale: Silent mutations alter the DNA but due to codon degeneracy,
the same amino acid is incorporated, so no change in protein sequence occurs.
14. Which of the following is true about meiosis?
A) It produces two diploid daughter cells.
B) It produces four haploid daughter cells.
C) It occurs only in somatic cells.
D) It does not involve crossing over.
Answer: B Rationale: Meiosis consists of two divisions resulting in four genetically
unique haploid cells (gametes). Crossing over occurs in prophase I, increasing
genetic diversity.
15. What is the primary function of the cell membrane?
A) To provide rigid structural support
B) To control the movement of substances in and out of the cell
C) To produce energy
D) To store genetic material
Answer: B Rationale: The cell membrane is selectively permeable, regulating
transport via diffusion, osmosis, and active transport. Rigid support is provided by
cell walls (plants, bacteria), energy production occurs in mitochondria, and genetic
material is stored in the nucleus.
16. Which of the following is an example of a carbohydrate?
A) Enzyme
B) Hemoglobin
C) Cellulose
D) Testosterone
Answer: C Rationale: Cellulose is a polysaccharide carbohydrate that forms plant
cell walls. Enzymes and hemoglobin are proteins; testosterone is a steroid lipid.
Questions with Correct Answers and Rationales Latest
Update.
Introduction
This practice exam is designed to help you master the biology content assessed on
the ATI TEAS 7. It includes 200 multiple-choice questions covering all major
biology topics: cell structure and function, macromolecules, DNA and protein
synthesis, cell division, genetics and inheritance, evolution, metabolism, and
microbiology. Each question is followed by the correct answer in bold and a
detailed rationale in italics to reinforce your understanding. Use this resource to
identify strengths and weaknesses, and to build confidence for test day.
1. Which organelle is responsible for producing ATP through cellular respiration?
A) Nucleus
B) Ribosome
C) Mitochondrion
D) Golgi apparatus
Answer: C Rationale: Mitochondria are the powerhouses of the cell, generating ATP
via aerobic respiration. The nucleus houses DNA, ribosomes synthesize proteins,
and the Golgi modifies and packages proteins.
2. What is the primary function of ribosomes?
A) Lipid synthesis
B) Protein synthesis
C) DNA replication
D) Detoxification
Answer: B Rationale: Ribosomes translate mRNA into polypeptide chains, making
them the site of protein synthesis. Lipids are synthesized in the smooth ER, DNA
replication occurs in the nucleus, and detoxification is a function of peroxisomes
and smooth ER.
3. Which of the following is a characteristic of both prokaryotic and eukaryotic cells?
A) Membrane-bound nucleus
,B) Mitochondria
C) Ribosomes
D) Endoplasmic reticulum
Answer: C Rationale: Ribosomes are found in all cell types because they are
essential for protein synthesis. Prokaryotes lack membrane-bound organelles such
as a nucleus, mitochondria, and ER.
4. During which phase of the cell cycle does DNA replication occur?
A) G1 phase
B) S phase
C) G2 phase
D) M phase
Answer: B Rationale: Synthesis (S) phase is when DNA is replicated. G1 is cell
growth, G2 is preparation for mitosis, and M phase is mitosis and cytokinesis.
5. A cell is placed in a hypertonic solution. What will happen to the cell?
A) It will swell and burst.
B) It will shrink due to water leaving the cell.
C) It will remain unchanged.
D) It will undergo active transport.
Answer: B Rationale: In a hypertonic solution, water moves out of the cell by
osmosis, causing the cell to shrink (crenate). Swelling occurs in hypotonic
solutions, and isotonic solutions cause no net movement.
6. Which of the following is the monomer of proteins?
A) Nucleotide
B) Monosaccharide
C) Amino acid
D) Fatty acid
Answer: C Rationale: Proteins are polymers made from amino acid monomers.
Nucleotides form nucleic acids, monosaccharides form carbohydrates, and fatty
acids form lipids.
7. What type of bond is formed between amino acids in a polypeptide chain?
A) Hydrogen bond
B) Ionic bond
C) Peptide bond
D) Disulfide bond
Answer: C Rationale: Peptide bonds are covalent bonds formed by dehydration
synthesis between the carboxyl group of one amino acid and the amino group of
,another. Hydrogen bonds contribute to secondary structure, and disulfide bonds
stabilize tertiary structure.
8. Which of the following correctly describes the function of the Golgi apparatus?
A) Digests worn-out organelles
B) Synthesizes ribosomal RNA
C) Modifies, sorts, and packages proteins
D) Produces ATP
Answer: C Rationale: The Golgi apparatus modifies proteins (e.g., adding
carbohydrates) and packages them into vesicles for transport. Lysosomes digest
waste, the nucleolus synthesizes rRNA, and mitochondria produce ATP.
9. In a DNA molecule, adenine (A) pairs with:
A) Guanine (G)
B) Cytosine (C)
C) Thymine (T)
D) Uracil (U)
Answer: C Rationale: In DNA, A pairs with T via two hydrogen bonds; G pairs with
C. Uracil replaces thymine in RNA.
10. Which organelle contains digestive enzymes that break down cellular debris?
A) Peroxisome
B) Lysosome
C) Vacuole
D) Ribosome
Answer: B Rationale: Lysosomes are membrane-bound vesicles containing
hydrolytic enzymes that digest waste, pathogens, and damaged organelles.
Peroxisomes break down fatty acids and detoxify hydrogen peroxide.
11. What is the product of transcription?
A) Protein
B) mRNA
C) DNA
D) ATP
Answer: B Rationale: Transcription is the process of copying a DNA sequence into
messenger RNA (mRNA). Translation then converts mRNA into a protein.
12. Which of the following is a function of the smooth endoplasmic reticulum?
A) Protein synthesis
B) Lipid synthesis and detoxification
C) ATP production
, D) Packaging of proteins
Answer: B Rationale: Smooth ER lacks ribosomes and is involved in lipid synthesis,
carbohydrate metabolism, and detoxification of drugs/poisons. Rough ER
synthesizes proteins, and the Golgi packages them.
13. A mutation that changes a single nucleotide but does not change the amino acid
specified is called:
A) Missense mutation
B) Nonsense mutation
C) Silent mutation
D) Frameshift mutation
Answer: C Rationale: Silent mutations alter the DNA but due to codon degeneracy,
the same amino acid is incorporated, so no change in protein sequence occurs.
14. Which of the following is true about meiosis?
A) It produces two diploid daughter cells.
B) It produces four haploid daughter cells.
C) It occurs only in somatic cells.
D) It does not involve crossing over.
Answer: B Rationale: Meiosis consists of two divisions resulting in four genetically
unique haploid cells (gametes). Crossing over occurs in prophase I, increasing
genetic diversity.
15. What is the primary function of the cell membrane?
A) To provide rigid structural support
B) To control the movement of substances in and out of the cell
C) To produce energy
D) To store genetic material
Answer: B Rationale: The cell membrane is selectively permeable, regulating
transport via diffusion, osmosis, and active transport. Rigid support is provided by
cell walls (plants, bacteria), energy production occurs in mitochondria, and genetic
material is stored in the nucleus.
16. Which of the following is an example of a carbohydrate?
A) Enzyme
B) Hemoglobin
C) Cellulose
D) Testosterone
Answer: C Rationale: Cellulose is a polysaccharide carbohydrate that forms plant
cell walls. Enzymes and hemoglobin are proteins; testosterone is a steroid lipid.
