Mendelian Genetics, Pedigrees, Asexual/Sexual Reproduction, Mitosis/Meiosis, and Natural Selection+

Chromosomes

Each human cell has 46 (23 pairs) half from mother and half from father, Contains genetic information, Made of DNA and protein

Alleles

Specific and varying forms of genes: (Ex- Eye color) - said term could be (Ex- Blue eyes) to the gene

Homozygous

A pair of identical alleles within a pairing (Ex- AA or aa)

Heterozygous

A pair of differing alleles within a pairing (Ex- Aa)

Genotype

An individuals allele pairing for a specific gene (Ex- AA, Aa, aa)

Phenotype

An individuals inherited and expressed gene from a pair of alleles (Ex- AA= A, Aa= A, aa=a)

Punnet Squares

The format used to calculate the potential genotypes of offspring

Dominant Traits

Traits that take over/DOMINATE in their genotypes when included. Shown through capital letters

Recessive Traits

Traits that are overpowered by dominant traits. (Yet can be carried by an Aa genotype, and are only expressed through an aa genotype.) Shown by lowercase letters

Co-dominance

When two Dominant traits mix

Ex- Speckled Chickens

Incomplete Dominance

When the Dominant Trait is not fully expressed when the recessive allele is in the genotype

Ex- Snapdragons

Pedigrees

The recorded family tree - usually used to track specific traits.

Pedigree Symbols

Circle=Female & Square=Male

Pedigree Shading Meaning

Shaded= Inherited the specific tracked trait

Half Shaded = Carries the tracked trait

Not Shaded = Does not have the tracked trait

Males. . .

Cannot be carriers of Sex-Linked traits, as they only have a singular X chromosome (XY)

(Can only have A or a/possess trait)

Asexual Reproduction

1 Parent, No Sex Cells (Gametes), No fertilization, Offspring is identical, No evolution importance (clones), Faster process

Sexual Reproduction

2 Parents needed, Needs Sex Cells (Gametes), Requires fertilization, Offspring has a mix of parental traits, Evolutionary importance (adaption), Slower process

Mitosis

Duplication/Division (Divided twice) of body cells (Not gametes)

Interphase (Before PMAT- Mitosis/Meosis)

The process of the duplication of DNA as the cell prepares to enter Mitosis/Meiosis)

Where do Mitosis/Meiosis take place?

The Cells (in the Nucleus)

The P In PMAT (Mitosis)

Prophase- The Chromosomes start to condense and turn visible (The Nuclei dissolves- spindles form)

The M in PMAT (Mitosis)

Metaphase- The Chromosomes align in the middle of the Nucleus (Single File)

The A in PMAT (Mitosis)

Anaphase- The Chromosomes move and split (Now Chromatids) to the poles of the cell via their spindle fibers.

The T in PMAT (Mitosis)

Telophase- New Nuclei form at both ends of the cell

Cytokinesis (The stage after PMAT)

The cytoplasm of the cell splits into two to finish the Mitosis/Meiosis process.

Centrioles

Barrel-shaped organelles in the cell. Duplicate and move to the poles of the cell in prophase, and make the spindle fibers to pull chromosomes.

Meiosis Process

PMAT 1 & PMAT 2

The P in PMAT 1 (Meiosis)

Prophase 1 & Chromosome Crossing- Homologous Chromosomes (Same Size/Gene type) match up and exchange genetic information. (Makes recombinant chromosomes)

Nuclei dissolves-Spindles form

The M in PMAT 1 (Meiosis)

Metaphase 1 - Chromosomes align in PAIRS in the middle of the Cell

The A in PMAT 1 (Meiosis)

Anaphase 1 - The Chromosomes are pulled away to the poles of the cells via their spindle fibers.

The T in PMAT 1 (Meiosis)

Telophase 1 - New Nuclei form at the poles of the cell-

Followed by Cytokinesis to make two brand new cells

The P in PMAT 2 (Meiosis)

Prophase 2- Spindles form- no Chromosome crossing

The M in PMAT 2 (Meiosis)

Metaphase 2- Chromosomes line up in the middle (single file this time)

The A in PMAT 2 (Meiosis)

Anaphase 2- Chromatids pulled away by the spindle fibers to the poles of the cell.

The T in PMAT 2 (Meiosis)

Telophase 2- Nuclei reform

Cytokinesis follows to split the cells

Sperm and Egg Cells/ Gametes

Contain 23 Chromosomes each - unique and un identical to the cells that produce them due to the divided chromosomes (Causes variety in siblings)

Formed through Meiosis

Meiosis

The Duplication/Division (divided 4 times) of gametes (Not other types of body cells)

Natural Selection

Mechanic of evolution, organisms with traits that help them adapt and survive easier in their environments are most likely to live and reproduce to pass those traits down to their offspring.