Mitosis vs. Meiosis, Heredity & DNA

Flashcards for Cell Division, Heredity & DNA

What is Mitosis

Cell division that produces body (somatic) cells.

What is Meiosis

Cell division that produces sex (gamete) cells - sperm/egg.

Mitosis Use

Growth and repair.

Meiosis Use

Reproduction.

Mitosis Result

2 identical diploid cells (2n).

Meiosis Result

4 unique haploid cells (n).

Mitosis purpose

Maintenance for body cells.

Meiosis purpose

Making eggs/sperm.

Prophase

Chromosomes condense (visible & thick).

Metaphase

Chromosomes line up in the middle (single file).

Anaphase

Sister chromatids pulled away to opposite sides.

Telophase

New nuclei form. Cell starts to split.

Cytokinesis

Cell fully splits into 2 identical diploid cells.

Prophase I

Chromosomes pair with homologous partners and crossing over happens.

Metaphase I

Pairs of chromosomes line up in the middle.

Anaphase I

Entire chromosomes pulled apart (not chromatids yet).

Telophase I + Cytokinesis

2 cells form.

Prophase II

Chromosomes condense again (no crossing over).

Metaphase II

Chromosomes line up single file.

Anaphase II

Chromatids pulled apart.

Telophase II + Cytokinesis

Total of 4 haploid cells created.

Heredity

Traits are passed from parents to offspring.

DNA

A nucleic acid made of a Sugar (deoxyribose) + Phosphate + Nitrogen Base in a Double helix shape that stores genetic instructions.

RNA

A nucleic acid made of a Ribose + Phosphate + Nitrogen Base in a Single strand shape that helps make proteins.

mRNA (Messenger RNA)

Copies DNA & takes it to ribosomes.

rRNA (Ribosomal RNA)

Makes up ribosomes (protein factories).

tRNA (Transfer RNA)

Brings amino acids to ribosomes.

Transcription

DNA → mRNA.

Transcription

Happens in the nucleus; Enzyme: RNA Polymerase; DNA → mRNA strand (complementary bases).

Translation

mRNA → Protein.

Translation

Happens at ribosomes in the cytoplasm; mRNA read in codons (3 bases = 1 amino acid); tRNA brings matching amino acid using an anticodon; Amino acids link into a polypeptide chain → Protein!

Gene

Section of DNA coding for a protein.

Chromosome

Tightly wound DNA around proteins (histones).

Structural genes

Code for proteins traits (eye color, enzymes).

Regulatory genes

Control when/where/how other genes are used.