Question 1

Which of the following best explains why plants appear green to the human eye?

Accepted Answer

Chlorophyll pigments absorb mostly purple/blue and red wavelengths, reflecting green light.

Question 2

A scientist inhibits the enzyme rubisco in a plant cell. Which of the following would be the most immediate effect?

Accepted Answer

The Calvin cycle would be unable to fix carbon dioxide, halting the production of G3P.

Question 3

Which of the following statements about the role of carotenoids in photosynthesis is correct?

Accepted Answer

Carotenoids act as antioxidants, neutralizing free radicals formed by high-energy light.

Question 4

If a plant is placed in the dark, which of the following best describes what will happen to the Calvin cycle?

Accepted Answer

The Calvin cycle will stop once ATP and NADPH produced by the light reactions are depleted.

Question 5

Which of the following best describes the difference between C3, C4, and CAM plants in terms of carbon fixation?

Accepted Answer

C3 plants do not separate carbon fixation from the Calvin cycle, C4 plants separate them in space, and CAM plants separate them in time.

Question 6

A researcher uses a restriction enzyme to cut a DNA molecule. Which of the following outcomes is most likely?

Accepted Answer

The enzyme will cut the DNA only at specific nucleotide sequences.

Question 7

Which of the following best explains why CRISPR/Cas9 is considered a revolutionary tool in gene editing?

Accepted Answer

It is cheaper, faster, more precise, and can cause both loss-of-function and addition of genes.

Question 8

A patient is diagnosed with a genetic disease caused by a faulty protein. Which gene therapy approach would most likely be used to correct this?

Accepted Answer

Insert a healthy allele into the patient's cells using a viral vector.

Question 9

Which of the following is a key difference between mitosis and meiosis?

Accepted Answer

Mitosis produces cells with the same chromosome number as the parent, while meiosis halves the chromosome number.

Question 10

A cell is observed to have two centrosomes, chromosomes lined up at the center, and spindle fibers attached to kinetochores. Which stage of mitosis is this cell most likely in?

Accepted Answer

Metaphase

Question 11

A mutation causes a proto-oncogene to become permanently active. What is the most likely consequence?

Accepted Answer

The cell will undergo uncontrolled division, increasing cancer risk.

Question 12

Which of the following best describes the role of tumor suppressor genes in preventing cancer?

Accepted Answer

They inhibit cell growth and differentiation, acting as brakes on the cell cycle.

Question 13

A human cell with 47 chromosomes, including three copies of chromosome 21, is an example of which condition?

Accepted Answer

Trisomy

Question 14

Which of the following mechanisms does NOT contribute to genetic diversity during sexual reproduction?

Accepted Answer

Replication of DNA during interphase

Question 15

A woman with genotype $$Aa$$ for a gene marries a man with genotype $$aa. $$What is the probability that their child will be homozygous recessive?

Accepted Answer

$$0.5$$

Question 16

Which of the following best explains why most aneuploidies involving large chromosomes result in embryonic death?

Accepted Answer

Large chromosomes contain more genes, so extra or missing copies disrupt more cellular functions.

Question 17

In a testcross, an individual with an unknown genotype is crossed with a homozygous recessive individual. If all offspring display the dominant phenotype, what is the genotype of the unknown parent?

Accepted Answer

Homozygous dominant

Question 18

Which of the following events occurs during prophase I of meiosis but not during mitosis?

Accepted Answer

Pairing of homologous chromosomes and crossing over

Question 19

A plant cell is observed forming a cell plate during cytokinesis. Which of the following is true?

Accepted Answer

The cell is a plant cell, and vesicles are fusing to form new cell wall material.

Question 20

Which of the following best describes the principle of segregation as it relates to Mendelian genetics?

Accepted Answer

Homologous chromosomes separate during meiosis, so each gamete receives only one allele for each gene.

Comprehensive Study Guide: Photosynthesis, DNA Technology, Cell Division, and Genetics

Study Guide - Practice Questions

Study Guide - Flashcards