Gentics (Mitosis)

Science 30

DNA (Deoxyribonucleic acid)

Where all the gentic info of a cell is contained in a nucleus

Chromotin

long strands of DNA. When DNA is preparing to divide chromatin is wrapped around a histone protein

Chromosome

A strand of DNA that contains the instructions for making proteins

How many chromosomes do humans have

Humans have 23 pairs of chromosomes (46 total)

22 sets of autosomes

1 sex chromosome (XX=female) (XY= Male)

Homologous

Term used to describe the pairs of chromosomes that share the same size, shape, and gentic compostion

Karotype

when you pair homologous chromosomes together

Images of all the chromosomes in one cell

ordered from largest to smallest

Aminocentesis

We create karyotype charts to monitor the well-being of unborn babies

A procedure in which doctors take a sample of amniotic fluid and use it to make a karyotype chart

Helps doctors identify any chromosomal genetic disorders a baby may have while also finding out the sex (not common)

Genes

Specific segment of DNA that code for particular proteins

Diploid

Total number of chromosomes in every somatic (body cell) of an organism

Half comes from dad half comes from mom

Denoted as 2n= n+n

46

Haploid

Total number of chromosomes in the gametes (sex cells) of an organism

only half the normal amount

denoted as n

23

The Four Main phases of the cell cycle

G1

S(Synthesis)

G2

Mitotic phase

Mitosis

The division of a somatic (body cell) into two identical daughter cells

used for- growth and development of body cells

asexual reproduction in unicellular organisms

1. Prophase

Chromatin condenses into sister chromatids joined by a centromere

Nuclear membrane dissolves

Centrioles (organelles that provide attachment for spindle fibres) move to opposite poles

Spindle fibres form from centrioles

Metaphase

Chromosomes line up in the middle of the cell along the equatorial plate (metaphase plate)

A spindle of fibre attaches to each chromosome

Anaphase

Centromeres divide, sister chromatids pullaway to opposite poles and each sister chromatid is now a chromosome

Two identical sets of chromosomes will be found at each pole

Telophase

Chromosomes begin to decondense into chromatin, and the nuclear membrane forms. The clevage furrow begins to form

Cytokenesis

Also known as cell division