← Home
Biology: Genetics & Evolution
Question
What is a gene?
tap to flip
Answer
A section of DNA that codes for a specific protein (or functional RNA), determining a particular characteristic.
tap to flip
Question
What is a chromosome?
tap to flip
Answer
A long, coiled strand of DNA found in the nucleus. Humans have 46 chromosomes (23 pairs) in most body cells.
tap to flip
Question
What is the difference between genotype and phenotype?
tap to flip
Answer
Genotype is the genetic makeup (alleles) of an organism; phenotype is the observable physical expression of those genes.
tap to flip
Question
What is an allele?
tap to flip
Answer
A version of a gene. Most organisms have two alleles for each gene — one inherited from each parent.
tap to flip
Question
What is the difference between dominant and recessive alleles?
tap to flip
Answer
A dominant allele is expressed even if only one copy is present. A recessive allele is only expressed when two copies are present (homozygous recessive).
tap to flip
Question
What does homozygous mean?
tap to flip
Answer
Having two identical alleles for a gene (e.g. AA or aa).
tap to flip
Question
What does heterozygous mean?
tap to flip
Answer
Having two different alleles for a gene (e.g. Aa).
tap to flip
Question
What is DNA?
tap to flip
Answer
Deoxyribonucleic acid — a double-helix molecule made of nucleotides. It carries the genetic instructions for the development and function of living organisms.
tap to flip
Question
What are the four bases in DNA?
tap to flip
Answer
Adenine (A), Thymine (T), Cytosine (C), and Guanine (G). A pairs with T; C pairs with G (complementary base pairing).
tap to flip
Question
What is a mutation?
tap to flip
Answer
A change in the DNA sequence. Mutations can be beneficial, neutral, or harmful, and are the ultimate source of genetic variation.
tap to flip
🔒
See all 30 cards for free
Create a free account to unlock the full deck — no payment needed.