GCD 3022 lecture 1

lecture 1

The cellular structure that contains the genetic material

chromosomes

DNA in prokaryotes

A singular chromosome located within the nucleoid

DNA in eukaryotes

Nucleus contains most of the DNA within chromosomes, with small quantities of DNA in the mitochondria and chloroplasts. The nucleus

Cytogenetics

Microscopic study of chromosomes

How are chromosomes viewed in cytogenetics

Actively dividing cells contain tightly condensed chromosomes, chromosomes can be photographed and a karotype

What is a karotype

A complete set of chromosomes

What is a diploid

A cell with two sets of chromosomes

What is a haploid

Cell with 1 set of chromosomes

Homologues

Pair of same chromosome, similar in sequence with same genes but contain different alleles.

Genes on homologous chromosomes have

same loci

Why aren’t sex chromosomes homologous

X and Y chromosomes are fundamentally different structures varying in size, number of genes, etc.

What is the product of the eukrayotic cell cycle

A genetically identical daughter cell

G1 phase

Initial growth stage of cell cycle, it increases in size, duplicates organelles, and produces proteins needed for DNA replication

S phase

DNA replication produces pairs of sister chromatids

G2 phase

Sister chromatids have been produced, cell makes final preparation for mitosis

M phase

includes process of mitosis followed by cytokinesis

Somatic cell

Nonreproductive cells found throughout body

What kind of cells are somatic cells

diploid

Gametes

Sperm and egg cells (sex)

Type of cell for gametes

haploid

Why aren’t gametes gentetically identical

They contain only 1 homologous chromosome from each pair

How do somatic cells divide

mitosis

How do gametes divide

meoisis

What is the product of mitosis

Two genetically identical daughter cells

What is the product of meiosis

4 genetically unique haploid cells