BIO103 - Unit 3 - Mitosis/Meiosis

the study of biochemical mechanisms of inheritence

Molecular biology

many of our genotypes do not become ______

phenotypes

Percentage of DNA base composition is shared between ___ ___ but not ___ ___

same species, different species

DNA is ____ stranded while RNA is ____ stranded

double, single

what the “ribbons” and “rungs” are made of in dna

sugar-phosphate backbone and nitrogenous bases

what makes RNA and DNA structurally different

DNA lacks an extra oxygen (deoxyribose)

RNA has an extra oxygen (ribose)

5’ and 3’ refer to the

carbon numbers in DNA’s sugar backbone

directional relation of leading and lagging DNA strands

antiparallel

DNA forms a ____ ____ when copying

replication bubble

protein that keeps DNA from refolding

single-stranded binding (SSB)

tells DNA Polymerase where to begin

Primer

enzyme that adds the appropriate nucleotides to the chain

DNA polymerase

unzips DNA by breaking the hydrogen bonds between base pairs

helicase

enzyme that relieves tension during DNA splitting

topoisomerase

enzyme that joins okazaki fragments together

ligase

short segments that occur in the lagging strand during DNA replication

okazaki fragments

places short sequences of RNA on the DNA strands

primase

How does DNA polymerase differ from RNA polymerase?

Only DNA polymerase has a proofreading ability

To begin transcription, RNA polymerase must bind to a segment of DNA called the_________.

promoter

The site where the two original DNA strands separate and active replication occurs is called the ___

replication fork

specific, short, repeated sequences of DNA that protects the ends of linear chromosomes from nucleases

telomeres

Messenger RNA molecules contain information that is used to synthesize_________.

polypeptides

Ribosome movement along the mRNA is called ___

translocation

Because the two strands of a DNA molecule are_________ to each other, either one can be used as a template to reconstruct the other.

complementary

During_________, a ribosome assembles a polypeptide whose amino acid sequence is specified by the nucleotide sequence in a molecule of mRNA.

translation

stage of mitosis in which the cytoplasm is split and two cells are produced

cytokinesis

what chromosomes are made of

protein and DNA

The stage of mitosis in which DNA replication occurs

interphase

a replicated chromosome

sister chromatid

joins sister chromatids together to make them one unit

centromere

stage of mitosis in which the nucleus is still intact, but the chromosomes are condensing

prophase

What stage of mitosis is this cell in?

Prophase

What stage of mitosis is this cell in?

Metaphase

stage of mitosis in which the chromosomes line up in the center of the cell

metaphase

stage of mitosis in which spindle fibers pull the chromotids to opposite sides of the cell

Anaphase

What stage of mitosis is this cell in?

Anaphase

What stage of mitosis is this cell in?

Telophase

stage of mitosis in which a cleavage forms and there are two nuclei in the cell

Telophase

how prokaryotes reproduce

binary fission

the strand of DNA that is copied by RNA

template strand

first stage of transcription

initiation

second stage of transcription

elongation

third stage of transcription

termination

where does transcription occur in a cell

nucleus

stage of transcription in which RNA polymerase binds to a promoter

initiation

stage of transcription in which amino acids are added to a polypeptide chain

elongation

stage of transcription in which a cap is added to the 5’ end and a poly-a tail is added to the 3’ end

termination

a protein-RNA complex that removes introns from eukaryotes

splicosomes

types of RNA

Messenger RNA

Transfer RNA

Ribosomal RNA

the stage of protein synthesis in which nucleotide sequences are converted into amino acid sequences

translation

the two stages of protein synthesis

translation and transcription

genes code for ____

protein

a unit of DNA wrapped around core of histone proteins

nucleosome

thickened DNA

chromatin

a cell with two sets of chromosomes

diploid

a cell with only one set of chromosomes

haploid

3 stages of interphase

G1

S

G2

Cell division checkpoints

G1

G2

M

The main cell division checkpoint

G1

The cell division checkpoint that comes before mitosis

G2

The cell division checkpoint that comes before spindle assembly

M

Signalling proteins that trigger growth for plasma membrane to receive

growth factors

tumor suppressor on chromosome 17

p53 gene

programmed cell death

apoptosis

enzyme that disassembles a cell for apoptosis

caspases

what forms during cytokinesis in animal cells

cleavage furrow

what forms during cytokinesis in plant cells

cell plate

types of cloning

reproductive

therapeutic

protein that holds chromatids together at centromere

cohesin

attachment site for microtubules*

Kinetochore

stage of interphase in which cells undergo majority of growth

G1

stage of interphase in which DNA is replicated

S

stage of interphase in which motor proteins coil chromosomes, tubulin synthesize, and centrioles replicate

G2

industry sector that uses living organisms to produce products/processes

biotechnology

an organism whose genome has been modified

genetically modified organism

a GMO that has had genes from another species inserted into its genome

transgenic organism

molecular scissors used to “cut out” the desired gene sequences

restriction enzymes

staggered cuts caused by restriction enzymes

sticky ends

stage of protein synthesis where DNA is copied into RNA

transcription

the leading strand is synthesized __ to __, and the lagging strand is synthesized __ to __

5’ to 3’; 3’ to 5’

how many times does interphase occur before meiosis?

once

chromosomes that are similar in shape, size, and gene type

homologous pairs

during what stage of meiosis does genetic recombination (crossing over) occur

prophase 1

site of genetic crossing over

chiasmata

chromosomes that have crossed over

recombinant chromosomes

how is prophase 1 in meiosis different from prophase in mitosis

In prophase 1, the homologous pairs match up and crossing over occurs

how is anaphase 1 in meiosis different from anaphase in mitosis?

the chromosome pairs are getting pulled instead of the chromatids

how is prophase 2 different from prophase 1?

crossing over does not occur and homologous pairs do not match up (much like prophase in mitosis)

when chromosomes do not properly separate

nondisjunction

3 ways meiosis increases genetic diversity

crossing over

independent assortment

random fertilization

disorder that comes from an extra copy of chromosome 21

down syndrome

disorder caused by multiple x chromosomes

klinefelters syndrome

disorder causes by and extra x chromosome, and no y chromosome

trisomy x

disorder caused by having no x chromosomes

turner syndrome

The specific physical position of a particular gene on a chromosome.

Genetic Locus

The mixing of genes between homologous chromosomes during Prophase I

Crossing Over or genetic recombination

randomly shuffles maternal and paternal chromosomes

Independent Assortment

Gametes carrying an abnormal number of chromosomes, such as having an extra chromosome ($n+1$) or missing a chromosome ($n-1$), resulting from nondisjunction.

anueploid gametes

The male gamete-producing process

Spermatogenesis

The female gamete-producing process occurring within the ovaries

Oogenesis