Biology Lecture Notes on DNA, Mitosis, Meiosis, and RNA

These flashcards cover key concepts related to DNA, the cell cycle, mitosis, meiosis, RNA types, and genetic mutations from the provided lecture notes.

What is asexual reproduction in eukaryotes mainly achieved through?

Mitosis.

What phase of the cell cycle is characterized by the cell resting and conserving energy?

G0 phase.

During which phase of mitosis does the nuclear envelope break down?

Prophase.

What occurs during metaphase of mitosis?

Chromosomes move to the center of the cell and line up.

What is the end result of mitosis?

Two identical daughter cells with 46 chromosomes each.

Define incomplete dominance. Give an example.

A blending of phenotypes; for example, pink flowers from red and white flowers.

How does codominance differ from incomplete dominance?

In codominance, both alleles are fully expressed, such as in blood type AB.

What are polygenic traits?

Traits that fall on a continuous scale, such as skin color, height, and intelligence.

What is the purpose of meiosis?

To produce four unique haploid cells from one diploid cell.

What is the significance of Rosalind Franklin in the study of DNA?

Her work in X-ray crystallography helped reveal the structure of DNA.

What is the role of helicase in DNA replication?

To unzip the DNA strand.

What are Okazaki fragments?

Short DNA segments synthesized on the lagging strand during DNA replication.

How does RNA differ from DNA structurally?

RNA is single-stranded, contains uracil instead of thymine, and has ribose sugar instead of deoxyribose sugar.

What are the three types of RNA?

Messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA).

What is transcription and where does it occur?

The process of synthesizing RNA from DNA; it occurs in the nucleus.

What is the genetic code read in?

In groups of three nucleotides called codons.

What is a mutation?

A heritable change in genetic information that can affect protein function.