Exam 3 WVU BIO

mutations

• changes in the sequence of nucleotides + DNA

• changes proteins

point mutations

change in a single nucleotide

base substitution

• 1 mutation

• progeria is an ex

base deletion

1 nucleotide removed

base insertion

1 nucleotide added

chromosomal aberrations

• gene deletion

• gene relocation

• gene duplication

mutations are corected by

enzymes

mutations are the source of

variation

what causes mutations

1. spontaneous mutations

2. radiation mutations

3. chemical-induced

cell division is necessary for

maintenance of the body:

1. growth + development

2. reproduction

3. repairment/ wound healing

unzips DNA during replication

DNA helicase

steps of DNA replication

1. DNA unzipped by helicase

2. DNA polymerase copies DNA

3. new nucleotides (mRNA) added to 3rd end

1 parent strand + 1 new strand =

daughter strand

DNA polymerase makes 1 mistake and…

corrects it

2nd major cause of death in the US

cancer

BPA

does the same thing as estrogen + leads to most cancers

cancer =

unregulated cell division

ends of chromosomes that wear off over time

telomeres

apoptosis

cell death

4 steps needed for cancer

1. DNA mutation

2. mutation activates oncogene = cell division

3. inactivated tumor suppressor = tumor

4. more tumors

protects from cancer/ REGULATED cell division

proto-oncogenes

protects from tumors

tumor suppressor gene

stimulates rapid cell division/ cancer

oncogene

stages of cancer

1. small tumor forms

2. spreads to tissues

3. large tumor forms, spreads to lymph nodes + adjacent tissues

4. spreads to organs + distant lymph nodes

cancer treatments

chemo + radiation

piece of DNA that contains several genes

chromosome

DNA + protein =

chromatin

how many chromosomes do you get from each parent

1

how many chromosomes does each person have

46

identical copy of a cell

sister chromatid

same chromosome, but from each parent

homologous chromosome

holds sister chromatids together

Centromeres

somatic body cell =

mitosis

reproductive gamete cell =

meiosis

cell cycle of a somatic body cell (in between division)

1. GAP 1 - primary growth phase

2. DNA synthesis - replication

3. GAP 2 - 2nd growth phase prep for CD

4. mitosis

5. interphase

mitosis cycle overview

1. interphase - DNA copied

2. mitosis- DNA splits

3. cytokinesis - parent cells cut in half = makes 2 identical cells

mitosis

1. prophase - sister chromatids condense + spindles migrate

2. metaphase - sister chromatids line up in the middle + attach to centromeres

3. anaphase - spindle fibres contract + pull sister chromatids apart

4. telophase - microtubules dissolve + nuclear envelope reforms

splits animal cells in half

cleavage furrow

reduces chromosome by half

reduction division

contains 2 sets of every chromosome

diploid 2n

contain 1 set of each chromosome

haploid 1n

separated at the end of meiosis 1 (ana 1)

homologous cells

separated at the end of meiosis 2 (ana 2)

sister chromatids

2 important features of meiosis 2

1. reduction division

2. produces gametes

how many non-sex chromosomes

22

sex chromosomes

XY

3 copies of a chromosome

trisomony

1 copy of a chromosome

monosomy

unequal distribution of chromosomes during meiosis

non-disjunction

biotechnology

using tech to modify organisms, cells, + their molecules in order to get practical benefits

DNA finger printing

used as an individual identifier

cuts DNA at specific sites

restriction enzymes

separates DNA fragments of different sizes

gel electrophoresis

Short tandem repeats (STR)

sequences of DNA that repeat - differs from mom+dad

known fragment sizes

ladder

make sure everything’s running smoothly

controls

adding/ deleting, or translating genes from one org to another

genetic engineering 

recombinant DNA 

combo of DNA from 2 or more sources

transgenic organism

bioengineered organism that carries the genes of 2 or more organisms

CRISPR

is a genome editing system that finds specific DNA + fixes it

BT corn

BT has spores to kill bugs

GMO exs

1. insect resistance

2. herbicide resistance

3. faster growth + bigger bodies

cloning

process of making a genetically modified organism through nonsexual means

natural example of cloning

identical twins

3 types of clones

1. DNA cloning - copy DNA

2. reproductive cloning - fully-cloned individual

3. therapeutic cloning - development of cells/ tissues for healing

DNA cloning

2 identical copies of DNA made

types of stem cells

1. totipotent - most embryos

2. pluripotent - older embryos

3. multipotent - most adult