bio 9+10

a) purebred dogs

similar genetic make-up due to selective breeding
is this a form of….
a) purebred dog
b) mutts / mixed dogs

b) mutts / mixed dogs because they have considerably more genetic variation

greater gene pool to choose from and less likely to show genetic “problems”
is this a form of…..
a) purebred dog
b) mutts / mixed dogs

heredity

transmission of traits from one generation to the next

genetics

the scientific study of heredity

Gregor Mendel

who is the father of genetics?

phenotype

the PHYSICAL appearance or expression of a trait

genotype

the GENETIC makeup of a trait

true-breeding

_____ _______ varieties result when self-fertilization offspring all identical to the parent

P generation

true-breeding parental plants are the _ _______

F1 generation

hybrid offspring are the _ ________

F2 generation

a cross of F1 plants produces an _ _________

filial, siblings

in terms of F1 and F2 generations, what does the F stand for and what does it mean?

artificially cross pollinating

Mendel isolated purple and white flowers in pea plants and examined heritable factors by __________ _______ ________

monohybrid cross

a cross between two individuals differing in a single character is a ________ _______-

alleles

Mendel deduced that an organism has two genes (_____) for each inherited characteristic
alternative versions of genes

homozygous dominant

these genotypes are what?
AA

heterozygous

these genotypes are what?
Aa

homozygous recessive

these genotypes are what?
aa

homozygous

identical alleles

heterozygous

two different alleles

two

an organism gains ___ alleles for each characteristic

dominant allele

requires only one allele to be expressed - AA or Aa

recessive allele

requires two alleles to be expressed - aa

law of segregation

allele pairs separate from each other during the production of gametes

punnett square

a diagram that shows the four possible combinations of alleles that could occur when these gametes combine

the 3:1 ratio in the F2 generation

Mendel’s hypothesis also explains the _______________________ which is proven through punnett square

locus

the specific location of a gene along a chromosome

dihybrid cross

Mendel tried to determine how two characteristics were inherited
> follow two characteristics at once

law of independent assortment

states that alleles segregate independently of other allele pairs during gamete formation

9:3:3:1

what were Mendel’s findings for the dihybrid cross?

cystic fibrosis

most common lethal genetic disease in the United States is ________ ___________

recessive

is the CF allele recessive or dominant?

d) Caucasians / White-Americans

when dealing with cystic fibrosis, what race is most likely to have it?
a) Africans / African-Americans
b) Asian / Asian-Americans
c) Indigenous / Native-Americans
d) Caucasians / White-Americans

recessive diseases (a)

AA - normal
Aa - carrier
aa - affected / diseased

dominant diseases

AA - affected
Aa - affected
aa - normal

true

true or false:
most human genetic disorders are recessive

genetic information

ways to get _________ _________
> before conception
> during pregnancy
> after birth

heterozygous carriers

genetic testing can identify prospective parents who are ___________ ______ for certain diseases

predictive genetic testing

a form of testing that may inform people of their risk for developing genetic diseases

denied health care

the confidentiality and potential use of results of genetic testing can lead to _____ ______ _______

complete dominance

Mendel’s pea crosses always looked like one of the two parental varieties, a situation called ______ _______

incomplete dominance

the appearance of F1 hybrids falls between the phenotypes of the two parental varieties, which is called ______ ______

three

how many alleles for a single gene in the ABO blood group?

codominant

A and B alleles are ________

O-

what blood allele is the universal donor?

AB+

what blood allele is the universal recipient?

pleiotropy

one gene influences multiple characteristics (phenotypes)

increased resistance to malaria

carriers of sickle-cell diseases have ______ _________ ____ ______

a) Africans / African-Americans

when dealing with sickle-cell, what race is most likely to have it?
a) Africans / African-Americans
b) Asian / Asian-Americans
c) Indigenous / Native-Americans
d) Caucasians / White-Americans

genetic and environmental factors

many traits are affected in varying degrees by both _____ __ ______ ________

polygenic inheritance

multiple genes control, but only 1 phenotype
- ex:
> eye colour
> skin colour
> height

SRY

the Y chromosome has a gene, ___, for the development for testes
> absence of the SRY gene directs ovaries to develop

44

males and females have __ autosomes (nonsex chromosomes)

sex chromosomes

pair of ____ _________ (X & Y) that determine an individual’s sex

bacteriophages

Alfred Hershey and Martha Chase used __________ to determine if protein or DNA was the genetic material of T2, a virus that infects the bacterium Escherichia coli (E. coli).

X-Ray crystallography

a technique that determined that DNA is a double-stranded helix (James D. Watson and Francis Crick have credit, yet Rosalind Franklin may be the one that discovered it)

nucleotides

DNA and RNA are nucleic acid polymers composed of __________-

nitrogenous base + five-carbon sugar + phosphate group

the three structures that form a nucleotide are ________________________________________

sugar-phosphate backbone

nucleotides are joined to one another by a __________________ _________

DNA

what structure is this?
- double-helix
- A-T, C-G
- deoxyribose

RNA

what structure is this?
- single helix
- A-U, C-G
- ribose

negative, due to phosphates

what charge (negative/positive/neutral) does DNA have and why?

DNA replication (S phase)

> starts with the separation of DNA strands
> then enzymes use each strand as a template to assemble new nucleotides into complementary strands

semiconservative model

DNA replication follows a ___________ _____
> the two DNA strands separate
> each strand then becomes a template for the assembly of a complementary strand from free nucleotides
> each new DNA helix has one old strand with one new strand

antiparallel

DNA molecules are ________

DNA polymerase

add nucleotides only to the 3’ end of the strand

transcription in the nucleus

in terms of the central dogma, how does DNA —> RNA?

translation in the cytoplasm

in terms of the central dogma, how does RNA —→ proteins?

makes DNA

what does DNA polymerase make?

makes RNA

what does RNA polymerase make?

transcription

uses the same nucleotide “language”

translation

involves translating from the language of nucleic acid to the language of proteins (amino acids)

triplet code

the flow of information from gene to protein is based on a _____ _____

64

how many codons are possible when it comes to 1 amino acid being specified by a codon of 3 nucleotides?
a) 60
b) 64
c) 61
d) 62

20

how many amino acids are there?
a) 19
b) 10
c) 20
d) 25

true

true or false:
some amino acids have more than one possible codon

initiation

RNA polymerase attaches to the promoter and RNA synthesis starts

elongation

the newly formed RNA strand grows as RNA polymerase adds free nucleotides one at a time (makes mRNA longer!)

termination

RNA polymerase reaches the terminator DNA and detaches from the newly made RNA strand and the gene

introns

interrupting sequences that separate exons

exons

coding regions

eukaryotic mRNA

_______ ____ undergoes processing before leaving the nucleus

RNA splicing

removes introns and joins exons (expressed sequences) to produce a continuous coding sequence

5’ cap, Poly A tail

a ______ _____ and ___ _ _____ of extra nucleotides are added to the ends of mRNA
a) 3’ cap, Poly B tail
b) 3’ cap, Poly A tail
c) 5’ cap, Poly A tail
d) 5’ cap, Poly B tail

tRNA

> has an anticodon and an amino acid binding site
> anticodon binds to the RNA codon
> tRNA anticodon is bound by the mRNA codon

polypeptides

ribosomes have binding sites for mRNA and tRNAs and coordinate the synthesis of ___________

true

true or false:
ribosomes are composed of ribosomal RNA and protein

mutation

any change in the nucleotide sequence of DNA

nucleotide substitutions

the replacement of one nucleotide with another nucleotide

silent mutation

have no affect at akk

missense

produces a different amino acid

nonsense mutation

change an amino acid into a stop codon

positive

produce an improved protein that enhances the success of the mutant organism and its descendants

nucelotide insertions or deletions

of one gene or more nucleotides in a gene may… (continued into another question)

frameshift mutation

nucleotide insertions/deletions can cause a __________ _______, which alters the reading frame (triplet grouping) of the genetic message

mutagenesis

the production of mutations
> spontaneous!

mutagens

high-energy radiation such as x-rays and ultraviolet light
> chemicals!