CSS - PMS - CCE - PCS - General Science
Genetics
What is a mutation?
A. A type of protein digestion
B. Any temporary change in mood
C. A change in genetic material
D. Only cell growth
Correct Answer: C
Mutations are alterations in DNA sequence or chromosome structure/number.
CSS - PMS - CCE - PCS - General Science
Genetics
What process produces gametes with half the usual chromosome number?
A. Binary fission only
B. Transcription
C. Meiosis
D. Mitosis
Correct Answer: C
Meiosis reduces chromosome number and generates genetic variation in sexually reproducing organisms.
CSS - PMS - CCE - PCS - General Science
Genetics
What is a recessive allele in simple Mendelian inheritance?
A. An allele that is always lethal
B. An allele without DNA
C. An allele whose effect is masked by a dominant allele in a heterozygote
D. An allele that cannot be inherited
Correct Answer: C
A recessive phenotype typically appears when no dominant allele is present at that locus.
CSS - PMS - CCE - PCS - General Science
Genetics
What is a dominant allele in simple Mendelian inheritance?
A. An allele found only on Y chromosome
B. An allele that never produces a trait
C. An allele expressed in a heterozygote
D. An allele that must always be rare
Correct Answer: C
In simple dominance, a dominant allele influences phenotype when one copy is present.
CSS - PMS - CCE - PCS - General Science
Genetics
Which scientist is famous for foundational pea-plant experiments on inheritance?
A. Robert Hooke
B. Charles Darwin
C. Louis Pasteur
D. Gregor Mendel
Correct Answer: D
Mendel's experiments established key principles of particulate inheritance.
CSS - PMS - CCE - PCS - General Science
Genetics
What does phenotype refer to?
A. Only chromosome number
B. Only DNA sequence
C. Observable traits resulting from genotype and environment
D. Only mutation rate
Correct Answer: C
Phenotype includes measurable or visible traits influenced by genes and environment.
CSS - PMS - CCE - PCS - General Science
Genetics
What does genotype refer to?
A. An organism's genetic constitution for one or more loci
B. Only body mass
C. Only environmental conditions
D. Only visible appearance
Correct Answer: A
Genotype describes genetic information, while phenotype describes observable characteristics.
CSS - PMS - CCE - PCS - General Science
Genetics
What are alternative forms of the same gene called?
A. Alleles
B. Tissues
C. Enzymes only
D. Organelles
Correct Answer: A
Alleles are different versions of a gene at the same genetic locus.
CSS - PMS - CCE - PCS - General Science
Genetics
What molecule carries most hereditary information in cellular organisms?
A. Water
B. ATP
C. DNA
D. Glucose
Correct Answer: C
DNA stores genetic information in almost all cellular life.
CSS - PMS - CCE - PCS - General Science
Genetics
What is a gene?
A. A chromosome with no DNA
B. A functional unit of heredity represented by a DNA sequence that contributes to a product or trait
C. A protein only
D. A whole organism
Correct Answer: B
Genes are DNA sequences whose expression contributes to functional products and traits.