Cell Biology and Genetics

Flashcards summarizing key concepts from the Cell Biology and Genetics lecture.

What are the major stages of the cell cycle?

Interphase (G₁, S, G₂), Mitosis (M phase), and Cytokinesis.

What occurs during the S phase of the cell cycle?

DNA replication occurs.

What is the role of proto-oncogenes in the cell cycle?

They promote cell division, acting like a gas pedal.

What happens if a proto-oncogene is mutated?

It becomes always ON, leading to uncontrolled division.

What is the difference between haploid and diploid cells?

Haploid (n) has 1 set of chromosomes (gametes), while diploid (2n) has 2 sets (body cells).

What is the outcome of mitosis?

It produces 2 identical diploid cells.

What is nondisjunction?

It is the failure of chromosomes to separate, resulting in cells with too many or too few chromosomes.

What is the function of helicase in DNA replication?

Helicase unwinds the DNA.

What is co-dominance?

Both alleles are fully expressed (e.g., AB blood type).

What does a Punnett square show?

It shows the possible genotypes of offspring from two parents.

What is epistasis?

It is when one gene masks or modifies another gene.

How can you tell if a trait is recessive?

Recessive traits often skip generations and occur in offspring from unaffected parents.

What is an example of a polygenic trait?

Traits affected by multiple genes, such as skin color.