Offspring are genetically identical to the parent

Identical clones

Produces two daughter cells that are identical to the original parent

Prokaryotes contain a single chromosome with only a few proteins

Part of interphase

Cell doubles its organelles and accumulates materials needed for DNA synthesis

Growth occurs as organelles double

Part of interphase

DNA synthesis

DNA replication occurs as chromosomes duplicate

DNA + histones (proteins) = chromatin

(chromosomes can be stained)

Part of interphase

Cell synthesizes proteins necessary for cell division

Growth occurs as cell prepares to divide

Centromere

A pair of similar chromosomes in a diploid cell. Humans have 23 pairs of this

Paired chromosomes that code for the same traits (one inherited from each parent)

In animal cells, the membrane indentation between daughter nuclei, begins as anaphase nears completion

Deepens when a band of actin filaments (contractile ring) forms a circular constriction between the two daughter cells.

Cleavage furrow

Cytokinesis

Daughter chromosomes (each consisting of one chromatid) are moving toward the poles of the spindle

Sister chromatids are pulled apart

In plant cells, rigid cell wall surrounding plant cells does not permit _______ by furrowing.

Begins with formation of a cell plate which eventually becomes new plasma membrane between the daughter cells.

Main function is to produce sex cells

2n: 46 cells

1n: 23 cells

To reduce the chromosome number from diploid to haploid

To make sure each cell has a complete haploid set

To allow genetic diversity

Genetic recombination

High rate of reproduction

No genetic variation

Genetic variation

Need a partner

Oppurtunity cost

In ____, meiosis is a part of spermatogenesis.

Sperm

Interphase 1 duration: 1 week

In _____, meiosis is a part of oogenesis

Egg

Prophase II duration: from birth until eggs mature during ovarian cycle

In _____ ______ organisms, meiosis reduces the chromosome number in half

From diploid (2n) to haploid (1n)

Gametes (egg, sperm) are haploid

Fusion of two gametes forms a diploid zygote

Exchange of genetic material between nonsister chromatids of a homologous chromosome pair (bivalent) during prophase I of meiosis I.

Homologues are held together by _____

Regions where the nonsister chromatids are attached due to cross-over

Allows homologous chromosomes to separate independently

When homologues align at the equator, maternal or paternal homologue may be oriented toward either pole

Gametes produced by one person are gentetically different from the gametes produced by another person

Fusion of gametes causes combination of paternal genes

2^23 X 2^23 combinations

Homologous chromosomes pair forming a bivalent (synapsis)

Increases genetic variation by independent assortment and crossing over

Homologous pairs align at the metaphase plate

Bivalent

Independent assortment

2^n

Daughter cells have one chromosome from each homologous pair

Haploid

1n

Spindle disappears

Nuclei form and cytokinesis takes place

Each individual has two factors for each trait

The factors segregate during gamete formation

Each gamete contains only one factor form each pair of factors (meiosis)

Fertilization gives each new individual two factors (alleles) for each trait

Each pair of factors segregates independently of the other pairs

All possible combinations of factors can occur in the gametes

In which phase of mitosis are the chromosomes moving toward the poles?

-Prophase

-Prometaphase

-Metaphase

-Anaphase

-Telophase

If a parent cell has 14 chromosomes before mitosis, how many chromosomes will each daughter cell have after mitosis is complete?

-28

-14

-7

-Any number between 7 and 28

-7 in the nucleus and 7 in the cytoplasm for a total of 14

During which phase of meiosis do homologous chromosomes separate?

-Prophase II

-Metaphase I

-Metaphase II

-Anaphase I

-Telophase I

Explain the results of this cross if complete dominance occurs:

F = freckles present   f = freckles absent

Parents: Ff X FF

-These parents produce kids without freckles

-There is a 2:2 ratio of phenotypes

-If these parents reproduce they have a 100% chance of having a child with freckles

-If these parents reproduce they have a 50% chance of having a child with freckles

-I don't like freckles - should I draw a Punnet square here???

In this cross, complete domincance occurs: TtYy x ttyy

What is the phenotypic ratio?

-3:1

-1:1

-9:3:3:1

-1:1:1:1

-3:1:3:1

A child is an albino but neither parent express this trait

How would you explain this?

-The genes for albinism are dominant

-The genes for albinism are recessive

-The child's parents are both heterozygous for this trait

-Both a and c

-Both b and c