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Labs:
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Animal Body
Arthropods
Biochem
Cell Cycle
Cell Interactions
Cell Structure
Circulation
Respiration
Communities
Digestion
DNA
Ecosystems
Energy
Evolution Evidence
Future of
Biosphere
Genetic Engineering
Gene Function
Genetics
Hormones
Human Evolution
Immunity
Species
Interaction
Kidneys
Locomotion
Membranes
Mollusks
Mutation
Nervous
Non-Coelmic
Photosynthesis
Plant Physiology
Population Genetics
Population
Dynamics
Cellular Respiration
Sensory
Speciation
Taxonomy
Vertebrates
Vertebrate
Org
Vocabulary:
1,2,3,4,5,6,7,8,9,10,
11,12,13,14,15,
16,17,18,19,20,
21,22,23,24,25,
26,27,28,29,30,
31,32,33,34,35,
36,37,38,39,40,
41,42,43,44,45,
46,47,48,49,50,
51,52,53,54
Altering the Genetic Material
I. Mutations A. Point – single n.t. change
B. Frame Shift – changes reading frame
C. Transposition – whole gene moves (transposon)
D. Mutigen
1. Anything that causes a mutation
2. Radiation
3. Ionizing
a) X-ray
b) Gamma rays
c) Two stranded
break
d) Free radicals
4. Ultraviolet
a) Less energy
b) Won’t make
free radicals
c) Absorbed by double
ring structures
d) Double covalent
e) Bound in pyrimadines
f) Pyrimidine dimmer
g) Cut out n.t.
h) Break bond
i) Zeraderm pigmatesiss
E. Chemical Mutigens
1. Modify DNA bases
2. Affects base pairing
3. Add –OH or CH3
or others
4. Most are lethal
a) Nerve gas
b) Mustard gas
F. Spontaneous Mutations
1. Slipped miss pairing
2. Deletion – loose a few hundred
n.t.
3. Middle of codon deletion –
changes reading frame
G. Somatic mutations – body cells
H. Germline mutations – affect future generations
I. Translocation – part of one chromosome moves to a different chromosome
J. Inversion – section is inverted
K. Polyploid – more than the normal set 3n, 4n,
5n (can’t survive)
L. Aniploid – one chromosome more; 2n +1 ~>
can survive
M. Tumors
1. Growth of cells
2. Cancer
3. Metasysis – cells break off
and go to another place in the body
4. Two Types
a) Bone or muscle
or connective tissue – Sarcloma
b) Skin – Carsonoma
N. Carcinogen – causes cancer
O. Mutigens – causes a mutation, can be a carcinogen
II. Two Types of Genetic Recombination
A. Gene Transfer – one chromosome donates its info
to another chromosome (HIV)
B. Reciprocal Recombination – Eukaryotes, two chromosomes
trade segments (crossing ove r)
C. Chromosomal Assortment – arranging of chromosomes
(eukaryotes)
III. Plasmids in Bacterial Gene Transfer
A. Lederberg & Tatum
B. F-factor in prokaryotic cells 1.
F-factor encodes for fertility factors. These cells can pass plasmids.
Contain a replication origin & genes to accomplish this
a) Occurs through
reciprocal exchange
b) Recognition site
on plasmid
2. Consythesize – a pilus; hollow
tube that connects E. coli
3. Conjugation – exchange of
genetic material in bacteria
4. Rolling circle replication a)
Sends a single strand of plasmid DNA across conjugation bridge into next
cell
b) \Transformation
IV. Transposition (bacterial)
A. Transposon – gene that has moved from location
on the genome to the other
B. Transposing gene encodes for transposase (enzyme)
which inserts segments into chromosome
C. Causes mutation due to insertional inactivation
D. Oncogenes – code for CdKs, or for EGF
E. Change in gene position ~> gene mobilization ~>
generate composite plasmids (ex. ab-resistance)
V. Reciprocal Recombination – (Eukaryotic) – 2 Way Exchange
A. Crossing Over
1. Prophase I – synaptonemeal
complex
2. Increase genetic variation &
new combination of mutants
B. Gene Conversion
1. Homologous of syn. comp. Are not
identical
2. n.t. may not be complete (mismatch
pairs)
3. Cut one n.t. out, replace w/ compliment
~> 2 matching chromosomes
4. One sequence is lost & converted
to the other
C. Unequal Crossing Over
1. One chromosome gets more than the
other
VI. Gene Organization
A. 6 classes of Eukaryotic DNA - based on # of copies
present
1. Satellite DNA
a) Short repeated
n.t. sequences near the centromere perform structural functions (4%)
b) Untranscribable
2. Transposons
a) Larger than sDNA
b) Many copies of
these genes
c) Jump randomly
along a chromosome
3. Tandem Clusters
a) Genes that encode
for proteins that the body needs a lot of
b) They are close
together and are separated by “spacer regions”
c) Ex. rRNA
4. Multigene Families
a) Groups of different
genes working together
b) Sequence similarities
5. Dispersed Pseudogenes
a) “Silent
genes”
b) Inactivated by
a mutation in the promoter
c) Ex. Frameshifts
& deletions
6. Single Copy Genes
a) Only one copy
of gene
b) Result of unequal
crossing over
c) Addition or deletions
VII. Transfection
A. Taking tumor cell and cutting it up
B. Cutting out DNA that causes the tumor (cancer)
C. Most occur because of mutations in gene which regulates
cell cycle
D. Oncogenes
1. Code for check point proteins
2. GF (growth factors)
3. CdKs
4. GF receptors
E. Receptors are mutated to have lower threshold
F. Tumor suppressor gene
1. Check DNA for structural defects
2. Prevents binding of CdKs and cyclin
G. P53 – cause of 50% of cancer
H. P16
1. Another tumor suppressor gene
2. Doesn’t allow CdK’s and
cyclins to bind
I. Mutation of 4 genes to cause cancer
J. 40 genes that could cause cancer
K. ras gene, ras protein
1. Altered causes cancerous ras protein
VIII. Structural Motifs
A. Proteins bind to DNA
B. Inhibitors & promoters
C. Methal groups and H-bonding help bind to major groove
D. Homeotic genes – deal with limb placements
E. 4 Motifs
1. Helix – Turn – Helix
a) Two alpha helices
separated by non-helical segment
b) Occur in pairs
and occur at right angles
c) Strong bonds
(strength)
2. Homeo Domain
a) Developmental
genes
b) Are similar sequence
of 20 AA, which always present themselves to the DNA in the same way
3. Zinc Fingers
a) Alpha helix bound
to a beta-sheet w/ molecules of zinc attached to it
b) More molecules
of zinc the stronger the bond
4. Leucine Zipper
a) Leucine is an
AA
b) Hydrophobic leucine
bound to second one which forms a “Y”
IX. Eukaryotic Characteristics
A. Enhancers – stimulate transcription of eukaryotic
DNA
B. Methylation – adding of –CH3 to genes is
like adding “spikes” therefore proteins can’t bind