Red-green color blindness is a sex-linked recessive trait in humans. Two people with normal color vision have a color-blind son. What are the genotypes of the parents?
XNXn and XNY
Q: Of the following human aneuploidies, which is the one that generally has the most severe impact on the health of the individual?
A: 47, trisomy 21
A couple has a child with down syndrome. The mother is 39 years old at the time of delivery, which of the following is the most probable cause of the childrens condition?
the mother likely underwent nondisjunction during gamete production
cytosine makes up 42% of the nucleotides in a sample of DNA from an organism. Approximately what percentage of the nucleotides in this sample will be thymine?
8%
the leading and lagging strands differ in that ____
the leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction
what is it meant by the description "antiparallel" regarding the strands that make up DNA
the 5' to 3' direction of one strand runs counter to the direction of the other strand
what is the role of DNA ligase in the elongation of the lagging strand during DNA replication
it joins Okazaki fragments together
In the process of transcription ___
RNA is synthesized
Codons are part of the molecular structure of ___
mRNA
what does it mean when we say the genetic code is redundant ?
ore than one codon can specify the addition of the same amino acid
which of the following occurs in prokaryotes but not in eukaryotes
concurrent transcription and translation
alternative RNA splicing
can allow the production of proteins of different sizes and functions from a single mRNA
A primary transcript in the nucleus of a eukaryotic cell is ___ the functional mRNA, while a primary transcript in a prokaryotic cell is ____ the functional mRNA
larger than , the same size as
which of the following types of mutation, resulting in an error in the mRNA just after the AUG start of translation, is likely to have the most serious effect on the polypeptide product
a deletion of two nucleotides
during a study session about evolution, one of your fellow students remarks "the giraffe stretching its neck while reaching for higher leaves; its offspring inherited longer necks as a result" which statement is likely to be helpful in correcting this student's misconception
characteristics acquired during an organism's life are generally not passed on through genes
which of these conditions are always tree of populations evolving due to natural selection?
Condition 1: the population must vary in traits that are heritable
condition 2: some heritable triast must increase reproductive success
condition 3: individuals pass on most traits they acquire during their lifetime.
conditions 1 and 2
which of the following must exist in a population before natural selection can act upon that population?
a genetic variation among individuals
if darwin had been aware of genes and of their typical mode of transmission to subsequent generations, with which statement would he most likely have been in agreement?
if natural selection can change one gene frequency in a population over the course of generations, then given enough time and enough genes, natural selection can cause sufficient genetic change to produce new species from old ones
which of the following evidence most strongely supports the common origin of all life on earth? all organisms ____
use essentially the same genetic code
*a DNA sequence is displayed and you use a codon chart thingy to help you find out which one sequences *
phe- smth - smth - smth
many crustaceans use their tails to swim. crabs don't use thier tail to swim. this is an example of ____
vestigal traits
what describes a mutuation where a single amino acid is deleted
a frame shift mutation
telomeres have been consered for a really long time. what does this indicate
they're useful
soon after the island of hawaii rose above the sea surface (somewhat less than one million years ago), the evolution of life on this new island should have been most strongly influenced by ___
the founder effect
an earthquake decimates a ground squirrel population, killing 98% of the squirrels. The surviving population happens to have broader stripes, on average, than the initial population. If the broadness of stripes is genetically determined, what effect has the ground squirrel population experienced during the earthquake
genetic bottleneck
which of the following is the most predictable outcome of increased gene flow between two populations
decreased genetic difference between the two populations
most swiss starlings produce four to five eggs in each clutch. Starlings producing fewer or more than this have reduced fitness. which of the following terms best describes this situation
stabilizing selection
why is the climate drier on the leeward side of mountain ranges that are subjected to prevailing winds?
pushed by the prevailing winds on the windward side, air is forced to rise, cool, condense, and drop its precipitation leaving only dry air to descend the leeward side.
the main reason polar regions are cooler than the equator is that
sunlight strikes the poles at a lower angle
it became apparent to watson and crick after completion of their model that the DNA molecule could carry a vast amount of hereditary information in which of the following
sequence of bases
who puts the neurotransmitters into the synapse?
A. the presynaptic membrane
B. the cell body
the cell body
why did hershey and chase use radioactive phosphorus to tag the DNA
there is phosphorus in DNA and not in proteins
why does calico happen only in female cats
because men only have one x chromosome to tell them their hair color
what abiotic factor would _____productivity in the ocean
light avaliability
what surviorship curve do people in a developed country have?
type 1
what survivorship curve does a species have if regular amount dies each year
type 2
when your body is digesting organic carbohydrate or smth, what does your body do with the excess
liver stores it as glycogen
which graph shows a population of bacteria that you grew in optimal conditions for two hours
the exponential one
which one is a producer
the one with all the arrows pointing away
which one can only be a primary consumer
only has ONE arrow pointing to it
which is likely a decomposer?
the one with all the arrows pointing at it
graph with an S like curve.
Which graph represents the carrying capacity?
C
*two graphs describing the precipitation and temperature*
1st graph: same temperature year round, lots of rain beginning of the year, dies down in the summer lots in the december.
2nd graph: cold in beginning of year, hot in summer, cold in end of year, like no rain
using the two graphs above, which statement could be true
graph one is describing a tropical rainforest
a fish goes from a river to an estuary, what is going to happen?
the one with the word osmosis is the right answer
what would result in resource partintioning
animals with similar ecological niches
after an animal is taken out of a ecosystem the spices number goes from 15 to 8, what was thaht animal?
a keystone species
what describes a topdown model in a grassland ecosystem
the one with bisons grazing
after your (some organ) takes insulin out of your blood, what happens?
your liver catalyzes glycogen
what is true about axons
a myelinated axon will have energy travel down the axon faster than a non myelinated axon
sodium potassium pump
taekes sodium out and pumps potassium in
if you're lying on the couch relaxing, what systems are being activated?
sympathetic is turned off, parasympathetic is turned on
what is a threshold?
electrical impulse string enough to open the sodium channels
what part of the heart has the strongest push smh smh aorta?
left ventricle
why are capillaries such low pressure
A. the cross section area is smaller than veins
B. the left ventricle isn't as strong as the right ventricle
C. the diastole isn't strong enough to pump blood
D. there are valves that slow down blood
C??
a group of birds go to an island that's next to a neighboring larger island, they eventually adapt to the plants and things were there and their beas change shape, 1-2 new birds fly from the nighborhing island every where, what does this do/mean
a. Slows down their adaptation to the food there
b. Speeds up their adaptation to the food on the island
c. colonization
b?
which graph represents a hare population that was put in an environment that also includes predators
the one that is an s curve but its real curvy at the top
which is a characteristic of k selected populations
a) offspring with good chances of survival
piece of dna and it has restriction enzymes l and ll, which cuts it into pieces a,b,c. if you put the DNA in a gel electrophoresis thingy, what will it look like?
C close to negtive side, A and B would be close to the positive side (A is closest to positive side because its smallest)
something about a mating call
behavioral isolation
H trait and T trait are not linked, if a mom is HhTt, what can one of her gametes look like
HT
What is perisralsis
smooth muscle contractions
why do villi have so many folds
to increase surface are and absorb more nutrients
why do we chew food?
to increase the surface area of the molecules so that enzymes can attach more efficiently
black (B) dominant fur color to brown (b) which is recessive. short hair (T) dominant hair length to long (t) hair which is recessive. BBtt, BbTt, if you cross those two animals what percent will have black fur, long hair
1/2
tick and dogs relationship
+/-
tree and thingy that lives in tree and takes it's nutrietns, tree has no known benefits
parasitism of faciliation
why doesn't it work if you put a mammalian piece of DNA in bacteria
bacteria can't break the guanine caps off
the reason why different biomes show up in different altitudes iss analogous to
the latitude
what is trye about proto-oncogene
promotes cell growth
what is true about tumor suppressor genes
inhibits fast dividing cels or something like that
two species in different lands have really similar characteristics that were due to the environment they're in, what does this describe?
convergent evolution
turnips have three colors, red, white and purple. when a red and white is crossed all the babies are purple. what is this an example of?
A. Codominance
B. Incomplete dominance
C. Multiple Alleles
D. something else
C or D idk
roan, what combination will make one red, roan, one white
roan x roan
what is an example of polygenic inheritance
anything like ahir, skin color, height, multiple factors make up the trait
when oen gene affects multiple things
pleiotrophy
idk what the question was
allopatric speciation
which phase correlates with mendels law of segregation
anaphase 1
what describes the phase that correlates with mendel's law of independent assortment
when the tetrads line up/ --> answer should escribe metaphase 1
why is it called monohybrid and dihybrid
monohybrid: crosses one trait
dihybrid: crosses two traits
what is the genotype of 11-5 (think that was the number)
ww
for a science fair project, two students decided to repeat the hershey and chase experiemtn with modifications. they decided to label the nitrogen of the DNA, rather than the phosphate. They reasoned thate ach nucleotide has only one phosphate and two to five nitrogens. Thus labeling the nitrogens would provide a stronger signal than labeling the phosphates. why won't this experiment work?
d) Amino acids (and thus proteins) also have nitrogen atoms; thus the radioactivity would not distinguish between DNA and proteins
hershey and chase set out to determine what molecule served as the unit of inheritance. they completed a series of experiments in which e. coli was infected by a T2 virus. which molecular component of T2 virus actually ended up inside the cell?
DNA
which of the following helps(s) to hold the DNA strands apart while they are being replicated?
d) single stranded DNA binding proteins
a new DNA strand elongates only in the 5' to 3' direction because ___
DNA polymerase can add nucleotides only to the free 3' end
DNA is synthesized through a process known as
semiconservative replication
researchers found e. coli that had mutation rates one hundred times higher than normal. which of the followings is the most likely cause these results
the proofreading mechanism of DNA polymerase was not working properly.
a single base subsitution mutuation is least likley to be deleterious whenthe base change results in
a codon that specifies the sane amino acid as the original codon
if cell X centers meiosis, and nondisjunction of one chromosome occurs in one of its daughter cells during meiosis 2, what will be the result of the completion of meiosis?
1/4 of the gametes descended from cell X will be n + 1 , 1/4 will be n-1, and 1/2 will be n