HV Midterm

Variation in a species is produced by ___________.

a and b

If both alleles at one locus in a person have the same DNA sequence, that person is ________.

a homozygote.

Homeostasis is the ability of an organism to maintain

a stable internal environment despite diverse, disruptive, external environmental influences

Which of the following is NOT an example of a DNA nucleotide pair?

all of the above

In order for an explanation of observed phenomena (hypothesis) to be considered scientific it must

be phrased in the form of question

T cells are a type of white blood cell that are produced in the ____________ (as are all red blood cells and white blood cells) and mature in the thymus gland below the sternal notch.

bone marrow

What type of DNA is neither subject to natural selection nor undergoes recombination and therefore makes a great way to track human migrations?

both a and b apply

A polygenic trait in an animal's phenotype such as height is ___________.

coded on multiple alleles.

A group of three tRNA nucleotides is called a ____________ because they code for a particular ______________.

codon....amino acid.

The likely fate of a rare allele in a small population is...

extinction

Where do the chromatids in the zygote's nucleus come from?

from the mother and father

One of the ways in which new alleles enter a population is when those carrying them join and mate with the "host" population that didn't have those alleles. This is called ____________.

gene migration

For a theory to be accepted, the following steps must be followed first _____________.

generation of a hypothesis, testing of the hypothesis by multiple observers, failure to reject the hypothesis

Native Americans had never experienced smallpox, measles or influenza before these diseases were introduced into the Americas by infected Europeans. An estimated pre-Contact North American population of approximately 12-15 million was subsequently reduced to less than 2 million. This phenomenon is known as _______________.

genetic drift/population bottleneck.

In order to be "fit", you must be able to survive and reproduce, and you must be able to do so in

in the environment you inhabit

There are a minimum of_________different alleles at one locus that determine whether you have type A, B or O blood.

3

Immediately after DNA replication in either mitosis or meiosis, how many chromatids are there?

92

Open Ended: Sickle-cell anemia is an interesting genetic disease. Normal homozygous individials (SS) have normal blood cells that are easily infected with the malarial parasite. Thus, many of these individuals become very ill from the parasite and many die. Individuals homozygous for the sickle-cell trait (ss) have red blood cells that readily collapse when deoxygenated. Although malaria cannot grow in these red blood cells, individuals often die because of the genetic defect. However, individuals with the heterozygous condition (Ss) have some sickling of red blood cells, but generally not enough to cause mortality. In addition, malaria cannot survive well within these "partially defective" red blood cells. Thus, heterozygotes tend to survive better than either of the homozygous conditions. If 9% of an African population is born with a severe form of sickle-cell anemia (ss), what percentage of the population will be more resistant to malaria because they are heterozygous (Ss) for the sickle-cell gene? Hardy Weinberg Equation= p2 + 2pq + q2 = 1

?

Your karyotype is made up of ______________.

? NOT: 46 chromatid pairs

An error in transcription or translation may result in ___________.

? NOT: a change in all of the tRNA that essentially shuts down the cell's protein production

While conducting a criminal or paternity case one would need to compare genetic relatedness of a suspect to available genetic evidence by "cutting up" DNA strands using ___ and running a gel electrophoresis test.

? NOT: endonuclease

At the periphery of contiguous territories, individuals on the border mate with each other. In the next generation, their offspring mate with others closer to the center of their own territory. This continues over many generations. No one is actually moving anywhere but alleles are being transferred over space anyway. This phenomenon is known as _____________.

? NOT: genetic drift

Some research suggests that pheromones in humans may (unconsciously) be used to______.

? NOT: sniff out genetic similarities when selecting a mate

Jean Baptiste Lamarck observed that animals develop certain abilities over the course of their lives. He concluded therefore that ___________.

? NOT: these abilities cannot be transferred from parents to offspring

The scientific method ______________.

? NOT: requires that a theory be generated first

Chromatids are composed of _____________.

DNA

An allele is ___________.

is a slightly altered form of a gene which codes for a trait

Natural selection acts by__________________

killing off genetic variants that are not fit in that environment

The healthy human body responds to foreign substances (this includes the protein coats on viruses) by producing antibodies and by rapid production of white blood cells, these are aka

leukocytes

In the process of transcription, what is happening?

mRNA is copying a message from DNA.

Being heterozygous for the sickle cell anemia allele gives you resistance to

malaria

A species is a group of similar animals that can _____________.

mate and reproduce fertile offspring.

Darwin's major contribution to the field of science was in explaining one of the mechanisms by which evolution operates. This mechanism is

natural selection

His phrase "survival of the fittest" was incorrectly attributed to Charles Darwin. He advocated letting "nature take its course" rather than helping those less fortunate, a concept specifically repudiated by Charles Darwin. His name was _________.

H. Spencer

_________ antigens are commonly used in mapping population movements in history because the viral assaults that populations have survived leave genetic markers.

HLA

Birth defects caused by mutation are likely to be more serious under what conditions?

If the mutation occurs early in the zygote development.

What increases human genetic diversity?

Invasions and Trade

Two different alleles may code for exactly the same protein because _____________.

of redundancy of codons for most amino acids.

Three of the following are functions of mitosis. Which one is NOT?

producing protein

The deductive method (by contrast with the inductive method) ______________.

requires the investigator to make their biases explicit in the form of a hypothesis

When DNA is replicating where do the DNA nucleotides in the NEW strands come from?

the cytoplasm

The two major purposes of meiosis are:

to produce genetic variation through recombination and to produce haploid sex cells with half a compliment of chromatids.

O is recessive, which means that to have type O blood, you have to have

two of the same allele that causes type O

The phrase "sampling error" means that __________.

you have a small, unrepresentative sample of a larger population.

Which of the following is NOT one of the types of cells found in the human body?

zygomatic cells

In order to achieve the Hardy-Weinberg Equilibrium in a breeding population certain conditions must occur. Which of the following is NOT one of those conditions?

Natural selection is in full force

According to the Hardy-Weinberg theorem, there should be no change in the frequencies of genotypes in a population over generations as long as 3 conditions are met. Which of the following is NOT one of those conditions?

P must equal Q

Which of the following is NOT one of the ways new genetic material is introduced into a breeding population?

Through an excess of pollen in the environment.

What is the biological definition of adaptation?

An increase in fitness over generations in a population.

Before human genographic projects allowed us to track human migrations through mtDNA and y-chromosome DNA, anthropologists relied on a variety of methods. Which of the following was NOT one of those methods?

Biblical evidence from the book of Genesis.

Your phenotype is exactly the same as your genotype.

False

____________ proposed that catastrophes were largely responsible for the variations we see among species on the planet today.

G. Cuvier

The substitution of a different single nucleotide pair during translation may result in no change to the protein product. Why?

There are several different codons with different RNA sequences that may produce the same protein.