Mitosis and Genetic Code Variation

These flashcards cover key concepts related to mitosis, the cell cycle, DNA variation, and mutations, aiding in understanding important biological processes.

Mitosis

Basic cell division that creates 2 identical cells for growth, replacement, and repair.

Cell Cycle

The series of events that take place in a cell leading to its division and duplication, including interphase, mitosis, and cytokinesis.

Interphase

The time between cell divisions, during which the cell prepares for division.

Metaphase

The stage of mitosis where homologous pairs line up end to end in the middle of the cell.

Anaphase

The stage of mitosis where sister chromatids separate and move to opposite sides of the cell.

Telophase

The final stage of mitosis where the chromosomes separate into two new cells.

Cytokinesis

The division of the cytoplasm, resulting in two daughter cells.

DNA Variation

Differences in DNA sequences that contribute to variation in phenotypes.

Central Dogma

The process by which the information in DNA is transcribed into RNA and then translated into proteins.

Codon

A three-base pair grouping in DNA or RNA that codes for a specific amino acid.

Start Codon

The codon 'ATG' that signals the start of protein synthesis.

Stop Codon

Codons (TAA, TGA, TAG) that signal the termination of protein synthesis.

Mutations

Changes in the DNA sequence that can alter the amino acid sequences produced.

Spontaneous Mutations

Mutations that occur naturally without external influence.

Induced Mutations

Mutations that result from exposure to external factors, such as UV rays.

Nucleotide Substitution

A mutation where a single nucleotide in the DNA sequence is replaced with another.

Silent Mutation

A mutation that changes a codon but does not change the amino acid it codes for.

Missense Mutation

A mutation that results in a change to one amino acid in the protein sequence.

Nonsense Mutation

A mutation that creates a premature stop codon, shortening the amino acid sequence.

Frameshift Mutation

A mutation caused by the insertion or deletion of nucleotides, altering the reading frame of the codons.

Mismatch repair

Enzyme building DNA corrects itself during replication

Excision Repair

DNA repair that cuts out the error and corrects it after replication

When do spontaneous mutations take place?

During DNA replication when there is a mutation that goes unfixed

When does cell replication happen?

S phase (synthesis)

Why is genetic code redundant but not ambiguous?

Multiple codons code for the same amino acid, but each codon has a specific amino acid it must code for

Start codon

ATG

Stop Codon

TAG, TAA, TGA

Sense Mutation

Changes in one letter in DNA that will change the stop codon to a regular amino acid making the sequence longer