Exam 1 Flashcards
Define genetics.
the science of dealing with heredity and variation. Seeks to find laws governing similarities and differences in individuals related by descent.
what makes up genetics?
inheritance, traits, and physical appearance.
in other words, it’s what makes you, you
define a gene.
blueprint for how the body looks.
what two things does heredity influence?
trait and character
what is selection used for?
to move the mean of the population
what does genetics measure and why?
traits, to improve animals
define animal genetics
the study of principles of inheritance of animals
define animal breeding
the application of principles of animal genetics with the goal of improving animals.
what is the purpose of animal breeding?
to improve the economic efficiency of livestock production, so the animal can reach market mode faster and cheaper.
what is the main tool of animal breeding
selection
what does selection do?
determines the parents of the next generation
what are the two types of selection
natural and artificial
what are the characteristics chosen for natural selection
strength
size
intelligence
color
defense strategies
flexibility
longevity
what animal was domesticated first
dog
what did domestication help with
resources, protection, and hunting
what is the domestication order
dog
goat
sheep
cattle
pig
llama
horse
camel
cat
chicken
guinea pig
turkey
rabbit
mouse
who was Robert Bakewell
the father of animal breeding
what is Bakewells purebred concept
in and in breeding (inbreeding to the max)
what is Bakewell’s process
set goals
early bull progeny test
record system
what does the purebred concept do?
increases homozygosity
improves uniformity
which sex drives gene improvement and why?
male, because they produce more
what is a downside of pure breeding
undesirable alleles are shown
what does the bull progeny test do
it rates the performance of offspring as opposed to the parent.
describe self domestication
select for tameness
strict captivity and limit breeding
intentional breeding
trait standardization
eliminate wild species
describe human domestication
control herd movement
eliminate problems
select for tameness
strict captivity and limited breeding
trait standardization
eliminate wild species
what three events led to modern genetics
Darwin’s “the origin of species”
Mendel’s “experiments in plant hybridization” and his two laws of segregation and independent assortment
Miescher isolating nucleic acid from pus cells.
who coined the term genetics?
Bateson
how many dna bases form a codon
3
why is selection used
to utilize fewer animals for the same amount if not more of product.
0-0.2 is _____ heredity
0.21-0.4 is _____ heredity
0.41-0.99 is _____ heredity
low
medium
high
heredity is not a ______ it is a __________
trait; measure
what is cryopreservation
freezing semen to use for AI
where is nuclear dna found?
nucleus
where does protein synthesis occur?
in the ribosomes
what did Miescher find in pus in 1868
nuclein, which is a phosphate-rich chemical from white blood cell nuclei
DNA has a ___________ backbone
phosphate
Describe Griffiths experiment
He used both smooth streptococcus pneumonia (S) which is virulent, and rough streptococcus pneumonia (R) which is nonvirulent. Injected S-strain (killed mouse), R-strain (mouse lived) heat-killed S-strain (mouse lived), and heat-killed S-strain with R-strain (mouse died).
dead S-strain + living R-strain = ?
living S-strain
Describe the Avery, MacLeod and McCarty experiment
Proved that over time, living R and dead S create living S. Protase ended in S cells, RNase resulted in S cells, ultracenfiguration results in S cells, but DNase resulted in R cells. Indicates a predominance of DNA. RNA and protein was destroyed.
Describe the Hershey and Chase (blender) experiment
Used T2 bacteriophage and bacteria. 32P for DNA and 35S for protein. the phage would attach to bacterium, and inject its genes into a host cell. the phage DNA replicates, and new particles assemble. the cell finally bursts, releasing new phage. Proved DNA was hereditary because DNA was found inside both the host and the cell.
what is bacteriophage
a virus
what makes up a nucleotide?
nitrogen base
phosphate
5-carbon sugar
what did Watson and Crick propose?
that DNA is a double helix
what is the diameter of DNA
2nm
A and T are _______ bonded, C and G are _________ bonded
double; triple
what is DNA
deoxyribonucleic acid
DNA is the _______________ of life
blue print
genes code for ________
protein
humans have __ chromosomes
46
cattle have __ chromosomes
60
sheep have __ chromosomes
54
goats have __ chromosomes
60
dogs have __ chromosomes
78
cats have __ chromosomes
38
chickens have __ chromosomes
78
pigs have __ chromosomes
38
turkeys have __ chromosomes
80
horses have __ chromosomes
64
donkeys have __ chromosomes
62
mules have __ chromosomes
63
camels, llamas, and aplacas __ chromosomes
74
rats have __ chromosomes
42
mouses have __ chromosomes
40
rabbits have __ chromosomes
44
what are the four DNA bases
adenine, thymine, guanine, cytosine
what base are A and G in
purine
what base are C and T in
pyrimidine
what is dna unzipped by in replication?
helicase
where are base pairs assembled
the parent template
the new DNA strand is ________ to the old one
complementary
what is DNA replication?
semi conservative
what are produced after DNA is unwound with helices
two daughter helices are produced
each strand is a _________
template
what does complementary base pairing
it ensures T pairs with A and G pairs with C
what are the four steps of replication
- original double helix
- stands separate
- complementary bases align opposite of the template
- enzymes link sugar-phosphate elements of aligned nucleotides in a continuous new strand
true or false: replication occurs at both ends
true
where does replication begin
the origin of replication
________ have multiple origins
eukaryotes
what does helicase do?
unwinds DNA and keeps strands from rejoining
what does primase do?
primes the DNA to find the beginning; does the majority of the work
how is the leading strand read?
5’ to 3’
how is the new strand read?
3’ to 5’
how is the lagging strand read?
3’ to 5’
how is the new strand from the lagging strand read
5’ to 3’
what stabilize the unwound parental DNA
single-stranded binding proteins
the leading strand is continuously ________
synthesized
the lagging strand is discontinuously ____________
synthesized
what do primase synthesize?
a short RNA primer, extended by DNA polymerase to form an Okazaki fragment
what does DNA ligase do?
it joins the Okazaki fragments to the growing strand
what does pol 3 do?
produces new strands of complementary DNA
what does pol 1 do?
fills in gaps between synthesized Okazaki fragments
what does DNA helicase do
unwinds the double helix