• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

Card Range To Study

through

image

Play button

image

Play button

image

Progress

1/199

Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

199 Cards in this Set

  • Front
  • Back
genome
all the genetic information in a cell
gene
unit if biological information encoded in dna
what parts of the cell carry dna
mitochondria
chloroplasts
nucleus
which gamete provides information for mitochondria and chloroplast development
the egg
chromosome
single dna strand with proteins

long and thin until condensed in cell division
chromatin
complex of dna and proteins that make up chromosomes
diploid
2 sets of chromosomes
haploid
1 set of chromosomes
somatic cells
diploid cells of the body
gametes
haploid reproductive cells
homologous pair
similar (near identical in physical shape and size) chromosomes

1 from mom
1 from dad
Are sex chromosomes homologous
no
autosome
all chromosomes other than sex chromosomes which are the same from male and female
sister chromatid(s)
products of DNA replication

2 chromatids are produced for each chromosome (replicating each strand of DNA)

They are identical
what are sister chromatids held by
cohesion @ centromere
Mitosis
division of the nucleus

chromosome sets are conserved
use of mitosis
asexual reproduction

somatic cell development and repair
Interphase
preparation for mitosis
G1-gap phase 1 (enzymes and proteins)
S- synthesis (DNA replication)
G2- gap phase 2 (more prep)
Prophase
sister chromatids connect and condense
nuceoli disappear
mitotic spindle forms, extending from centrosome (made of centrioles)
centrioles move towards pole
Prometaphase
microtubules attach to kinetochores
nuclear envelope breaks
Metaphase
spindles move to the poles
chromatids line up @ metaphase plate
Anaphase
sister chromatids are separated due to the polymerization and depolymerization of microtubules
Telophase
formation of nuclei
spindle breaks down
chromosomes decondense
Cytokinesis in animals
actin filaments form cleavage furrow and pinch
cytokinesis in plants
cell plate is formed via vesicles
polyploid
more than 2 sets of chromosomes

ex: wheat is 6n and oat is 8n
zygote
fertilized egg
n
number of unique chromosomes hat make a chromosome set
ploidy
number of sets (1n, 2n, etc)
human chromosome
46 (diploid)
karyotype
display of condensed chromosomes arranged in pairs (homologous chromosomes grouped)
germ cells
specialized cells in the ovaries and testes that will undergo meiosis to produce gametes
why does mitosis first duplicate and then divide
because cells that are reproduced would not be genetically similar which would lead to problems with carrying out cell function and communicating
what happens after a sperm succeeds to enter the egg
it changes its outer coating so that no other sperm can get in
Prophase I
chromosomes condense

homologs (they are previously duplicated from synthesis phase) will pair up to a tetrad, a process called synapsis (they become glued together by proteins)

homologs will exchange genetic information (crossing over) which will form chiasmata

nuclear envelope breaks down

spindle apparatus forms
what is a purpose of the chiasmata
to hold together homologs to ensure equal distrubution during metaphase I
Metaphase I
homologs attach to spindles and line up @ metaphase plate
Anaphase I
homologs are separated to poles
Telophase I
Cleavage furrow or cell plate develops and the nuclear envelope reforms

cytokinesis follows
Prophase II
chromosomes recondense and spindle apparatus forms

*no replication occurs
Metaphase II
sister chromatids (which are not identical due to crossing over) are attached to spindle apparatus and line up @ metaphase plate
Anaphase II
the sister chromatids are separated to opposite poles of the cells
Telophase II
Cleavage furrow or cell plate forms

nuceli form again

cytokinesis follow to produce 4 haploid daughter cells
How is genetic variation maintained
Independent assortment-you don't know where the m + d chromosomes will line up in metaphase I

crossing over- makes a new combination of alleles
how do you determine how many types of assortments are there
2^n

n = number of chromosomes in a set

ex: humans n = 23
what was the old idea of inheritance
the blending of traits

parental traits were blended like paint colors
what is the new idea of inheritance
that we inherent packets of information- genes
what were the 7 pea plant traits that mendel studied
Color
Flower position
Seed color
Seed shape
Pod Shape
Pod color
Stem length
What are 3 critical features of all the traits mendel studied
they were true breeding
they produced fertile progeny
no intermediates
How did mendel perform his monohybrid cross
he cut the stamen of one pea plant and pollenated the carpel of another pea plant (pea plants are self pollinating)
F1 generation
offspring of monohybrid truebreeding cross
F2 generation
offspring of self-pollinated F1 generation
alleles
alternative version of a genes
Law of Segregation
two alleles separates during gamete formation; one to each gamete
genotype
genetic makeup
phenotype
physical makeup
locus
chromosome location referring to a specific gene
testcross
used to determine the genotype of an unknown species

unknown x true breed recessive
law of independent assortment
each pair of alleles segregates independently of other allele pairs during gamete formation
product rule for independent events
probability of event 1 and 2

prob. 1 x prob 2
mutually exclusive rule (sum)
probabilty of event 1 or 2

prob. 1 + prob 2
monohybrid
heterozygous for one character
dihybrid
heterozygous for two characters
genotypic ratio for a monohybrid cross
1:2:1
phenotypic ratio for a monohybrid cross
3:1
a homozygous genotype makes how many types of alleles
1
a heterozygous genotype makes how many alleles
2
How many different types of games can a trihybrid make? (AaBbCc)
2 x 2 x 2 = 8 gametes
How many different gametes can rr Aa Bb Cc Dd make?
1 x 2 x 2 x 2 x 2 = 16 gametes
When determining the probability of a gamete that is contains more than one gene or trait, how do you calculate it?
take the individual probability for each allele and mutliple it

ex: what is the chance of Aa Bb Cc Dd producing an a b c d gamete?

1/2 x 1/2 x 1/2 x 1/2 = 1/16
When determining the probabilty of a zygote containing more than one traits, how do you calculate it
that the probability of the gametes that would produce that genotype

ex: In a self cross of Aa Bb Cc Dd what is the chance of producing a zygote aa bb cc dd

1/16 x 1/16 = 1/256
pleiotropy
a gene that affects multiple phenotypic traits
epistasis
a gene at one locus alter the phenotypic expression of a gene at a second locus
pleiotropy
one gene affecting multiple traits

ex: the gene that is responsible for sickle cell anemia is also responsible for things like pain, stroke, etc.
epistasis
the interaction of genes that control a specific trait
why are pedigrees important
because people can be crossed just for the sake of genetics
pedigree
the genetic family tree
carrier
heterozygous individual that has a recessive gene that corresponds to a disorder
square
male
circle
female
colored
affected
Give an example of epistasis
In order for blue primroses to be made, they must have dominant traits that code for rose colored and mauve colored primroses

In labradors, homozygous recessive leads to a yellow dog. However homozygous dominant or heterozygous leads to a brown or black dog. However, the color of brown or black is determined by a different set of genes. Homozygous recessive is brown, and dominant is black.
A Corn plant is a diploid plant with n = 10. How many sister chromatids are present at

mitotic metaphase?
meiotic metaphase I?
meiotic metaphase II?
n = number of homologous chromosomes in a set

diploid = 2n

Therefore somatic cells contain 20 chromosomes.

At mitotic metaphase synthesis has occurred, leading to double the amount of chromosomes = 40 (each chromosome has 2 chromatids)

At meiotic metaphase I, the same senario as above is occuring, so 40 chromatids.

At meiotic metaphase II, the homologous chromosomes have been separated, but not the chromatids, so the # divides in 1/2 to be 20 chromatids
3 processes unique to meosis that cause genetic variation
Crossing over (recombination between homologous chromosomes)

Segregation of homologous chromosomes

Independent assortment of nonhomologous chromosomes
where does the separation of sister centromeres occur?
anaphase and anaphase II
A cross is being made between A/A B/B C/C D/D x a/a b/b c/c d/d

a) What is the genotype of F1
b) how many different genotypes are possibly in the F2
c)what is the fractin of F2 individuals that will be phenotypically recessive for all 4 factors
a) A/a B/b C/c D/d
b) There are 3 different genotypes A/A A/a a/a, and four different genes. 3^4 = 81
c) Figure out the probability of a homozygous recessive gene. There are 4 options and 1 is homo rec. so 1/4. Multiply it 4 times to represent the 4 genes to get 1/256.
What is the 5 conclusions that resulted from mendel's experiments
1. each gene controls only 1 unique trait

2. 1 of the two alleles is dominant over the other

3. Two alleles for each gene

4. Phenotypes are not influenced by the environment

5. Each gene considered were on a different chromosome
What are examples that show that mendel's idea of 1 gene to one trait doesn't apply at all times
Epistasis: two or more genes control 1 trait

Pleiotropy: 1 gene for multiple traits

Polygenetic: Additive effects of 2 or more genes affect a phenotype
polygenetic inheritance
additive effect of 2 or more genes affect a single phenotypic characteristic
quantitative characters
not an "either-or" trait because they vary so much

like height or skin color
Give examples that show that mendel's idea that 1 allele always dominant is not always so
Incomplete dominance
Co-dominance
Incomplete dominance
where a heterozygous intermediate results that is between the homozygous dom and rec.
co-dominance and an example
the two alleles both affect phenotype

ex: blood in humans
AB blood type shows sugars that Ia and Ib correspond to
O blood type
no sugars

Io Io
B blood type
has B sugar

Ib Ib or Ib Io
AB blood type
Has A and B sugars

Ia Ib
A blood type
has A sugars

Ia Ia or Ia Io
what animal did morgan work on?
fruit fly
drosophila
what was the wild type of flies in morgan's experiments
red eyes
what was the mutant type of flies in morgans experiments
white eyes
what does w w/ a + signify in morgan's experiments
wild type
Explain morgan's fly experiment and his hypothesis that resulted from it
He crossed a wild type female w/ mutant male, produced all red eyed f1 kids.

He then crossed two F1 hybrids and got a result of the typical 3:1 phenotypic ratio. However, the white eyed flies were only male.

He concluded that it had to be sex linked
Who do males receive their Y chromosome from
dad
who do males receive their X chromosome from
mom
who do females get their x chromosomes from?
Have to have dads

and have 1 of 2 of moms
hemizygous
Partially dominant

ex: X carries dom paired w/ Y
what is the main purpose of the Y chromosome
sperm fertility
SRY
it is a gene that is responsible for the determination of sex.

The presence of it will lead to the development of testes in the gonads of a fetus
heterogametic
individuals that can produce gametes that contain one of the two types of chromosomes

ex: males are heterogametic XY
Sex linked genes in humans
gene physically on a sex chromosome

ex: color blind, hemophilia, muscular dystrophy

girl must be homozygous
boy must be hemizygous and receive it from mom
sex influenced
sex hormones that affect a trait

ex: baldness
sex limited
trait only found on one sex

beard, breasts, etc
What does a diamond mean in a pedigree
a hypothetical child (one yet to be born)
How do you know if a pedigree is carrying a trait that is autosomal recessive
If it has males that are unaffected (clue that it is not sex linked)

Heterozygous carriers are unaffected
How do you know if a pedigree is looking at a trait that is autosomal dominant
To see if it is not sex linked, looked to see if a particular gender is affected

Next, see if 1/2 of the children are affected
How do you know if a pedigree is looking at a trait that is x-linked recessive
Depending on how the parents are affected (homozygous or heterozygous), look at which gender is affected. Typically it will be only males that are affected.
How do you know if a pedigree is looking at a trait that is x-linked dominant
Typically, girls will be affected.

Once again, look at the parents genotype and remember the rules of passing chromosomes

Girls will always receive X from dad, boys will always receive X from mom. Girls will receive one of mom's two Xs
Barr Body
an inactive X chromosome that will line the nuclear envelope.

The chromosome protein and DNA structure has been altered
X inactivation in females
Females contain 2 X chromosomes, so one becomes inactive so as to not have too many genes competing.

This X inactivation is chosen at random between the two X chromosomes at embryonic development. As a result, about 1/2 of the cells in the body of a female will express one X chromosome and half will express the other X chromosome.
how many genes does the Y chromosome in humans have
78
how many genes does the X chromosomes in humans have
11,000
what scientist first described recomination
TH Morgan and his experiments on fruit flies
sex linked gene
refers to a gene on a sex chromosome
linked gene
two or more genes on the same chromosome that tend to be inherited together
Give examples of how sex is determined in other animals and how it differs from humans
Crickets- absence of X leads to males
Birds/Chickens- females have the different chromosome (ZW)
Bees-Haploid (unfertilized) = males and diploid leads to females
Fish-age will determine sex (they change throughout life)
Turtles-temperature that egg was growing at because the enzyme that is responsible for sex determination functions differently at temperature
Genes that are close together are typically inherited how
together
Genes that are typically father apart are inherited how
through independent assortment
Explain Morgan's experiments with flies and autosomal traits
Morgan crossed a homozygous wild type fly (grey w/ normal wings) with a homozygous mutant type (black w/ small wings)

They produced dihybrid offspring that looks like the wild type parent (grey and normal wing).

The dihybrid was crossed with a homozygous mutant type which lead to produce 2 children that looked like parents (wild type and mutant type) and 2 children that had altered phenotypes (1 that was grey w/ small wings and 1 that was black with normal wings)

The number of offspring that didn't look like parents were smaller in number than the offspring that did look like the parents
genetic recombination
the production of offspring with combinations of traits that differ from those found in either parent
parental types
offspring that look like parents
recombinant types
offspring that do not look exactly like parents
Review Morgan's experiments with flies and X-linked traits
It is basically the same as the autosomal traits

Make sure to do a cross to understand
Recombination frequency
total # of recombinant types / total number of progeny
According to mapping genetics, the father apart the genes, the _______ the probability that _______ will occur
the higher the probability that crossing over will occur
map unit
1% recombination frequency = 1 centimorgan
nondisjunction
results from a spindle that doesn't funciton properly

What results is that either homologous chromosome are not probably separated in Meiosis I or the sister chromatids are not properly separated in Meiosis II
Aneuploidy
an abnormal number of chromosomes
Trisomy
(2n +1)

When an abnormal gamete with an extra chromosome combines with a normal gamete
Monosomy
(2n -1)

When an abnormal gamete without a chromosome combines with a normal gamete
Down Syndrome
Trisomy 21

47 chromosomes

leads to extra 21st chromosome
Edwards syndrome
trisomy 18

extra 18th chromosome
Triple X syndrome
trisomy of sex chromosome X in girls

XXX
Klinefelter syndrome
trisomy of sex chromosome X in boys

XXY
Turner syndrome
the absence of an X chromosome

X
Supermale syndrome
The addition of a Y chromosome

XYY
Proteins are polymers of
amino acids
DNA is a polymer of
nucleotides
purines
A and G

2 C
pyrimidines
C and T

1 C
What were the two proofs that showed that DNA was genetic material
DNA could "transform" bacteria
DNA was shown to be the genetic material of bacterial viruses
transformation
change in genotype and phenotype due to the assimilation of external DNA into the cell
Explain the experiments of Griffith
Griffith did tests with a harmful and not harmful strain of bacteria in mice.

S. bacteria = virulent
R. bacteria= nonvirulent

Mice w/ S. bacteria = dead
Mice w/ R. bacteria = live
Mice w/ heat killed S. Bacteria = live
Mice w/ heat killed S. Bacteria and live R. bacteria = dead

The blood from the last mouse experiment was found to contain S. bacteria that was live.

*concluded that there was a transforming principle
Explain the experiments of Avery, McCarty, and MacLeod
They extracted protein, lipid, DNA, and carbs from S. bacteria and combined each w/ R. bacteria.

Only DNA turned the R. bacteria to S. bacteria
Explain the experiment of Hershey-Chase
They wanted to see whether proteins or DNA was incorporated into the host cell of bacteriophages.

They cultured phages in S35 (radioactive) which was incorporated into the protein of the phage. The phage was then exposed to bacteria cells. The phages were then thrown off the bacteria cells in a blender. The mixture was centifuged. This process also occured with P32 being incorporated into the DNA of the phage. Basically, what was shown was that DNA was what was incorporated into the cell.
Structure of DNA nucleotide
Phosphate to 5C
Deoxyribose
Base to 1 C
5'
Phosphate

beginning of DNA strand
3'
OH
DNA shape
antiparallel
double R handed helix
bond that links DNA backbone
phosphodiester
Watson and Crick
Discovered shape of DNA by compiling the ideas of many.

Chargaff: A =T and G= C
Pauling: DNA has multiple strands
Rosalind: x ray crystallography showed that dna was a helix that was 2 nm wide and repeated every 3.4 nm
DNA replication basic idea
H bonds are broken and each strand serves as a template based upon base complimentarity
3 models for DNA replication
conservative: old w/ old, new w/ new
semiconservative: old/new new/old
dispersive: old and new mixed
Meselson-Stahl experiment
cultured bacteria in N15 and then again in N14

DNA centrifuged after 1 replication which lead to a heavy/light mixture (ruled out conservative model)

2 replications: light and heavy/light (ruled out dispersive model)
Does DNA replication occur at one place?
No because it would take too long
In what direction does DNA replication occur?
both directions
replication fork
site where parental DNA is being unwound
Helicase
enzymes that untwist double helix at replication fork
Single Strand binding protein
bind to unwound DNA strands to stabilize
Can DNA polymerase begin replication?
No
What initiates DNA replication?
a RNA nucleotide chain called a primer which is synthesized by primase
How are nucleotides added during DNA replication
DNA polymerase will add nucleoside triphosphates that will use the energy of breaking the 3P

1 P stays and 2 leave
At what end, 5' or 3', does DNA elongation occur at the new strand in dna replication
at the 3' end
Leading strand
DNA strand that is made beginning at its own 5' end and moves to 3' end but it will begin at the 3' of the old strand which will allow for it to be made continuously

follow replication fork
lagging strand
DNA strand made beginning at it's 5' end and moves to 3' end. However, it has to be made in chunks because it is begins in the 5' end of the old strand.

It will move opposite to the replication fork.
How are the lagging strand fragments placed togher?
dna polymerase I will replace rna primer w/ dna and then dna ligase will bind all the fragments together
Telomeres
repeated nucleotide sequences that prevent shortening of dna sequences and allow for protection.

they are done by telomerase which adds nucleotides w/ its own RNA sequence
Genes code for
all proteins
General view of DNA to proteins
DNA ----> mRNA ---> protein
RNA structure
single stranded

phosphate bound to ribose bond to a base

A --> U
G --> C
Explain Transcription
RNA polymerase will bind to a promoter in the DNA sequence which contains a TATA box and transcription factors. RNA polymerase will open the DNA stand and will bind RNA complements to DNA together. Eventually RNA poly. meets a terminator sequence in the DNA and will leave.

**RNA polymerase only opens the DNA strands locally
What strand is the template strand in transcription?
3' to 5' end
3 steps of transcription
Initiation
Elongation
Termination
transcription factor
collecitn of proteins at the promoter that will help in binding RNA polymerase
Introns
parts of mRNA strand that do not code for proteins
Entrons
parts of mRNA strand that code for proteins
How is the mRNA strands finalized
The introns are spliced out

5' end gets a cap w/ a G
3' gets a poly A tail
Codon
triplet of RNA bases that code for 1 of 20 amino acids
tRNA
transfer RNA

responsible for interpreteing mRNA to proteins
structure of tRNA
they are a twisted RNA strand with an anti codon which is the compliment of its equivalent mRNA codon

binds to amino acids in the cytosol and brings them to ribosomes
amino actyl tRNA synthesases
proteins that aid the addition of amino acids to tRNA
Protein structure
polar molecule

amino group NH2 at one end
carboxyllic acid at the other end
general structure of an amino acid
R
NH2 - C - COOH
H
What binds amino acids together
peptide bond
Ribosomes
made of large and small subunits consisting of proteins and RNA molecules called ribosomal RNA
3 binding sites of ribosomes
P site: where tRNA holding peptide chain sits
A site: where tRNA holding next amino acid sites
E site: where tRNA exits
How is the peptide chain transferred in ribosomes
with the aid of GTP for energy the peptide chain is transferred from the P site to the A site
Explain the beginning of translation
small unit of ribosome binds
tRNA w/ methionine binds
large complex will then bind with the help of GTP
how does translation end
a stop codon will bind to the A site which will cause everything to disassemble
polyribosomes
strings of ribosomes that are synthesizing proteins on one mRNA strand