Bio Exam 3

3 functions of cell division

asexual reproduction

growth and development

tissue renewal

gametes

male or female reproductive cells

somatic

belonging to the body

mitosis

duplication of somatic cells

cytokinesis

the division of the cytoplasm

sister chromatids

identical copies of the same chromosome

Chromatin

condensed DNA and protein during division

the material that makes up eukaryotic chromosomes

Homologous chromosomes

chromosomes that contains the same genes but possibly different versions of each gene

same genes but different versions

genome

an entire set of DNA instructions in cells

Where are genes located for everyone and are they identical

Genes are identically spaced and in the same place for everyone but look different

What are the 2 states of DNA

unwound

packed

What is needed for a cell to make another cell

DNA and organelles are replicated, and DNA is condensed

Life cycle of humans

1n gamete to 2n zygote to mitosis then baby then adult

cell cycle

interphase (g1,s,g2)

M phase

G1

metabolic activity and growth

cell being cell

S

metabolic activity, growth, and DNA synthesis

G2

metabolic activity, growth, and preparation for cell division

haploid chromosomes vs diploid chromosomes

haploid are 1

diploid are 2

Why are humans diploids

we have 2 copies of each chromosome but sperm and eggs are haploid

centromere

holds sister chromatids together and attachment point for division

Mitosis phases

interphase

prophase

prometaphase

metaphase

anaphase

telophase

interphase occurs after chromosome replicated and each chromosome is composed of

sister chromatids with chromosomes that have replicated

Prophase

chromosomes condense and spindles begin to form

pro metaphase

nuclear envelope breaks down

metaphase

chromosomes complete migration to middle of cell

Anaphase

sister chromatids separate and pulled to opposite poles of cell

Telophase

nuclear envelope reforms spindle apparatus disintegrates

chromosome

a structure composed of a DNA molecule and associated proteins

what does chromatin consist of

a DNA molecule complexed with histone properties

chromatid

one strand of replicated chromosome with its associated proteins

Kinetochores

the structure on sister chromatids where kinetochore microtubules attach

What happens when sister chromatids separate during mitosis

they become independent chromosomes

Microtubule organizing center

any structure that organizes microtubules

Centrosome

the microtubule organizing center in animals

centrioles

cylindrical structures that comprise microtubules located inside animal centrosomes

What is cyclin

a regulatory protein

Cyclin dependent kinase (Cdk) catalyzes what

phosphorylation of other proteins to start mitosis

things needed to pass G1 checkpoint

cell size is adequate

nutrients are suficient

social signals are present- signal to divide

DNA is undamaged

things needed to pass G2 checkpoint

chromosomes have replicated successfully

DNA is undamaged

activated MPF present

things needed to check metaphase checkpoint

all chromosomes are attached to spindle apparatus

what causes cancer to form

cells breaking

cancer is a

large group of disease cause by irregular cell division

How do tumors form

cells dividing when not needed

Mitosis is division of

chromosomes

Cytokinesis is division of

cytoplasm

mitosis purpose

make new cells

meiosis purpose

make gametes

gamete

reproductive cell with half the number of chromosomes

gene

section of DNA that influences hereditary trait

allele

different version of the same gene

Ploidy

number of each type of chromosomes

Humans are

2n=46

meiosis makes

haploid gametes (sperm, eggs)

most of you chromosomes aren’t identical to your grandparents because of

mixing/ crossing over

Meiosis 1

separates homologous chromosomes

meiosis 2

separates sister chromatids

Cells produced in meiosis 1 are ? the same as the cells produced during mitosis

not

autosome

non sex chromosome

chromosomes 1-22 in humans

tetrad

homologous replicated chromosomes that are joined together

polyploid

having more than 2 of each type of chromosomes

triploid n=3 and so on

what organisms are haploid

bacteria

archaea

algae

plants

animal gametes

what organisms are diploid

familiar plants

animals

humans

what organisms are polyploid

seedless bananas (triploid)

ferns (tetraploid)

bread wheat (hexaploid)

what does sexual reproduction allow for

the shuffle and possibility of good traits that are different from you parents

what is independent assortment

a source of genetic variation in meiosis 1 that allows for equally probable genetic variation

number of cell divisions in mitosis vs meiosis

mi-1

me-2

number of chromosomes in daughter cells compared with parent cells in mitosis vs meiosis

mi-same number

me-half

Does meiosis or mitosis have synapsis homologs

meiosis

number of crossing over events in mitosis vs meiosis

mi- none

me-one or more per pair of homologous chromosomes

makeup of daughter cells in mitosis vs meiosis

mi-identical

me- different

why does the makeup of daughter cells in meiosis different

only one of each chromosome types present, paternal and maternal segments mixed within chromosomes

Roles in organism life cycle for mitosis

asexual reproduction in eukaryotes

cell division for growth of multicellular organisms

Roles in organisms for meiosis

procedes production of gametes in sexually reproducing animals

mitosis can occur in both diploid and haploid but meiosis can only occur in

diploid

where does DNA replication occur for mitosis

interphase, before mitosis

where does DNA replication occur for meiosis

interphase before meiosis 1 but not meiosis 2

Number of daughter cells and genetic composition of mitosis and meiosis

mi-2 genetically identical diploid daughter cells

me-4 unique haploid daughter cells

things we experiment on

mice, fruit flies, plants, worms, yeast

Mendels 4 hypothesis’s

alternative versions of genes that account for variations are inherited

for each character an organism inherits 2 alleles one from each parent

dominant traits are shown over recessive

sperm and egg carry one allele each

principle of segregation

2 members of each gene pair separate during gamete formation

cannot have 2 from dad or 2 from mom must be one from each

True breeding

varieties in which self fertilization produce all identical offspring for a trait

hybrid

offspring of 2 different varieties

P1 generation

F1 generation

F2 generation

p-parents

1-first generation after parents

2-second generation after parents where F1’s self fertilize or cross with one another

trait

a variant for a certain characteristic

Self fertilize

sexual reproduction with 2 gametes from the same parent

cross fertilization/ cross

sexual reproduction using gametes from different parents

genotype

the genetic composition of an individual

phenotype

the physical manifestation of an individuals genotype

Gene

a hereditary factor that influences a particular trait

allele

a form of a gene

the 2 alleles in a diploid may be the same of different

Dominant allele

an allele that produces its phenotype in the hetorsygous and homozygous form

recessive allele

an allele that produces its phenotype only in homozygous form

pure line

individuals of the same phenotype that when crossed always produce offspring with the same phenotype

hybrid

offspring from crosses between homozygous parents and different genotypes

reciprocal cross

a cross in which the phenotypes of the male and female are reversed compared with a prior cross

testcross

a cross between a homo recessive individual and an individual with the dominant phenotype but an unknown genotype

Autosomal

a gene located on any non sex chromosome (autosome) or a trait determined by an autosomal gene

incomplete dominance

F1 hybrid is an intermediate phenotype

complete dominance

seen in F1 only dominated traits shown

Linkage

2 genes that are close on the same chromosome