Download EOC Review Chapters6

Mendel, Mendel extended, DNA/RNA and
biotechnology
Coopercityhigh.net/webpages/lcoyne
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Law of Segregation- member of each pair of
alleles separate when gametes are formed. A
gamete will receive one allele or the other.
(anaphase I)
Law of Independent Assortment- pairs of
alleles line up independently of one another
during gamete formation (metaphase I)
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Mutations
Crossing over in prophase I
Independent assortment in metaphase I
Sexual recombination
Variations in DNA can cause variations in
organisms phenotype. This can result in the
evolution of the species as traits are selected
for and against
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Homozygous dominant- GG
Heterozygous- Gg
Homozygous recessive- gg
Genotype- GG, Gg, gg
Phenotype- green, yellow
Allele- alternate forms of a gene
Punnett square- used to determine probability of
a trait being passed to offspring
P= parents, F1= 1st generation of kids,
F2= 2nd generation of kids
Meiosis→Fertilization→Cleavage→Differentiation
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Two plants are crossed, the first is
heterozygous for height and has yellow
seeds. The second is heterozygous for
height and seed color. (Tall dominant over
short, Green dominant over yellow)
Genotype of parents Ttgg X TtGg
Create two monohybrid cross (TtX Tt and
ggXGg)
Multiply the fraction possibilities to get your
answer
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A. 0
B. 6
C. 9
D. 12
Answer C
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A. Both parent plants are heterozygous for flower
color.
B. Both parent plants were homozygous for
purple flowers.
C. One plant had white flowers and the other
was heterozygous.
D. One parent was heterozygous for flower color
and the other was homozygous with purple
flowers.
Answer A
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Incomplete dominance- neither trait is dominant
(red and white flowers make pink)
Codominance -(both are dominant) blood type
Sex linked- trait is found on the X chromsome
(males more likely to have these because they
only have one X chromsome)
Polygenic- several genes code for a trait (height)
Multiple Alleles- 3 or more possible alleles for a
trait (blood type/A,B,O)
Barr body- one X chromsome is shut down in
each female diploid cell
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Autosomal- found on chromosomes #1-22,
individuals need 2 recessive alleles to have
disease
◦ Huntington’s unusual because caused by dominant allele
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Sex linked- found on X chromosomes and males
are more likely to have disease because they
only have one X chromosome
Nondisjunction- chromosomes don’t separate
properly during Anaphase resulting in an extra
chromsome in gamete (down syndrome)
Autosomes (#1-22) sex chromosomes #23
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The allele for brown eyes is dominant to blue
eyes. Which best explains how two brown eyed
parents have a blue eyed child?
A. Each parent is carrying a recessive allele for
the trait.
B. Eye color is a sex linked trait and male children
could have only the allele for blue eyes.
C. Mutations after fertilization could alter gene
sequences and change alleles.
D. One parent must have had only blue eyed
parents.
Answer A
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Griffith proved transformation- bacteria pick
of DNA from environment (mice experiment)
 Composed
of nucleotides
◦ 5-C sugar (deoxyribose)
◦ phosphate group
◦ nitrogenous base
purines = adenine and guanine
pyrimidines = cytosine and thymine
phosphate group
nitrogen-containing
base
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Adenine- Thymine (uracil if RNA)
Cytosine- Guanine
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DNA Replication- process by which DNA
makes a copy of itself in order to produce
two identical cells
1. DNA is uncoiled with enzymes
2. DNA polymerase- enzyme which then
bonds the complementary nucleotides
together
3. Each new DNA molecule has one
original and one new strand
(semiconservative model)
new strand
nucleotide
DNA polymerase
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All organisms use the same 4 bases (ATCG)
It is the difference in order and arrangement
which results in the variety of life on earth
This demonstrates an evolutionary
relationship between organisms
The more shared DNA in the same order, the
more closely related two species are
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RNA- nucleic acid which acts as a
messenger between DNA and the ribosomes
for protein synthesis
Central Dogma- information flows from
DNA to RNA
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Structure- single stranded
5-Carbon sugar (ribose)
phosphate group
nitrogenous base
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purines- adenine and guanine
pyrimidines- cytosine and uracil
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Transcription- process by which information
is transferred from DNA to RNA in sets of
three nucleotides (codon)
◦ Introns are cut out and stay in nucleus, exons leave
◦ messenger RNA (mRNA)- copies and carries
information out of nucleus to ribosome
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Translation- decoding of mRNA in order to
form proteins (assisted by transfer RNAtRNA and ribosomal RNA - rRNA)
◦ tRNA reads in sets of 3 called the anticodon
◦ Amino acids are linked by peptide bonds to make
protein
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A. Only tRNA bends into specific shapes to
make amino acids.
B. Only mRNA can repair specific mistakes in
DNA code.
C. The tRNA is used on the ribosomes and
the mRNA is used in the nucleus.
D. The mRNA brings information to the
nucleus for the tRNA to use.
Answer A
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Random changes to DNA
Point mutation- one nucleotide is substituted
Frameshift mutation- insertion or deletion of
a base resulting in a shift as to how the
codon is read
Mutagens- agents which can change the DNA
(UV light, industrial chemicals etc.)
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A. 5
B. 4
C. 2
D. 3
Answer D
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A. Cells having the new DNA version will look or
operate differently from cells with the original DNA.
Only the sections of DNA without mistakes will be
used in the future so the DNA strand will shorten.
C. The DNA will be exactly like the original since only
the original strand of DNA is used as a template.
D. When the new strand is used as a template the
strand built from it will differ from the original DNA.
Answer D
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Cut desired gene and plasmid of bacteria with
same restriction enzyme
Combine desired gene and plasmid together
Insert recombinant plasmid into a bacteria
and allow to reproduce
Evidence that it worked- bacteria shows trait
(glows, produces chemical etc)
Gel Electrophoresis
DNA moves towards positive
side
The more bands that line up,
the more closely related
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Transgenic organisms- contain DNA from a
different species
Production of medicine like insulin, make
plants resistant to disease, pests, etc…, make
livestock produce more meat, milk…, test out
treatments for human diseases on other
organisms
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A. Nucleic acids are used as the building blocks of
proteins, while enzymes are used as the building
blocks of phospholipids.
B. Nucleic acids contain the genetic code for protein
synthesis, while enzymes catalyze chemical reactions
C. Nucleic acids inhibit biochemical reactions, while
enzymes catalyze reactions
D. Nucleic acids transmit signals that begin biological
processes, enzymes convert carbohydrates into lipids
and proteins.
Answer C