Genetic Material and Molecular Biology Concepts

These flashcards cover key vocabulary terms and concepts in genetics and molecular biology relevant to the provided lecture notes.

Chargaff's Rule

States that in a DNA molecule, the amount of adenine equals thymine (A=T) and the amount of cytosine equals guanine (C=G).

Nucleotide

The basic building block of nucleic acids, consisting of a sugar, a phosphate group, and a nitrogenous base.

Purines and Pyrimidines

Purines include adenine and guanine; pyrimidines include cytosine, thymine (DNA), and uracil (RNA).

Eukaryotic DNA Packaging

Eukaryotic DNA is tightly packaged with histones to form chromatin, which condenses to form chromosomes during cell division.

Histones

Protein molecules around which DNA is tightly coiled in chromatin.

Centromere

The region of a chromosome where the two sister chromatids are joined and where spindle fibers attach during cell division.

Telomere

The repetitive sequences at the ends of chromosomes that protect them from degradation.

Semiconservative Replication

The process by which DNA is replicated, resulting in each new DNA molecule containing one original strand and one new strand.

Replication Bubble

A region of DNA where replication has been initiated, and both strands serve as templates for new DNA synthesis.

Telomerase

An enzyme that extends the telomeres of chromosomes, counteracting the shortening that occurs during DNA replication.

Types of RNA

Includes messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA), each serving different roles in protein synthesis.

RNA Processing

The post-transcriptional modifications that RNA undergoes, including splicing, capping, and polyadenylation.

Alternative Splicing

The process by which different combinations of exons are joined together, leading to different mRNA variants from a single gene.

Okazaki Fragments

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

DNA Ligase

An enzyme that seals nicks in the DNA backbone, joining Okazaki fragments together.

Transcription

The process of synthesizing RNA from a DNA template.

Shine-Dalgarno Sequence

A ribosomal binding site in bacterial mRNA that is crucial for initiating translation.

5' Cap and Poly(A) Tail

Modifications added to mRNA that enhance its stability and facilitate its transport from the nucleus to the cytoplasm.

Codon

A sequence of three nucleotides that corresponds to a specific amino acid or stop signal during protein synthesis.