Anthropology Exam 1

Rapid rates of evolution would be most expected among species that:

Organisms such as bacteria and insects usually go through their life cycles very rapidly. As a result, their populations can respond to new natural selection pressures by evolving quickly.

Which of the following best describe how anthropologists primarily learn new information about humans?

Field work

Which of the following statements is true about Mendel?

He believed that genetic traits of parents will usually blend in their children. He gave us the basis for understanding genetic inheritance in all living things, including humans. His realization that we inherit units or genes was the key to it all.

Which of the following procedures has the lowest risk for an unborn child?

alpha-feto protein screening blood test

The synthetic theory of evolution is based at least in part on:

an acceptance of natural selection as a cause of evolution

Which of the following can be detected now by examining a karyotype?

an unborn child's gender or sex

Karyotyping can be done from:

any cell in your body

Autosomes

are all chromosomes other than the sex chromosomes

Incompletely penetrant genes are ones that:

are only expressed in the phenotype if certain factors in the environment are present. An example of an incompletely penetrant genetic inheritance is multiple sclerosis. M.S. apparently develops when an individual who carries the gene or genes for this disease is attacked by a virus that causes a flu-like illness.

Mendel believed that the characteristics of pea plants are determined by the:

We now call these units genes. Each inherited trait is determined by at least one gene from each parent.

Assuming that both parent plants in the diagram below are homozygous, why would all of the f1 generation have yellow phenotypes?

When there is a genotype that consists of a dominant and a recessive allele, the phenotype generally looks like the dominant one. In this case, yellow is dominant.

The sex chromosomes of normal females are:

X and X

Which of the following statements is true? a) In the real world, gene pool frequencies are inherently unstable. That is to say, they change by themselves without any evolutionary mechanism operating. b) Evolution is a common occurrence in natural populations c) A gene pool is a more or less distinct group of individuals within a species who tend to restrict their mate selection to members of their group.

b.

Polygenic traits are ones that are:

controlled by more than just a single pair of alleles Polygenic traits are determined by multiple pairs of alleles. Simple Mendelian rules of dominance do not readily apply. Human stature is an example. It results from all of the genes that determine the size of all body parts from head to foot.

Which of the following conditions can result in evolution in a population? a) all mating is totally random b) mutation is not occurring c) natural selection is not occurring d) none of the above

d none of the above

The sex chromosomes of females are ___________ and those of males are ___________ .

homologous; hemizygous

Godfrey Hardy and Wilhelm Weinberg concluded that gene pool frequencies are:

inherently stable. The frequencies of alleles in a gene pool will remain unchanged unless some evolutionary mechanism causes them to change. This does not mean that gene pool frequencies are usually unchanged, but, rather, that they do not change all by themselves.

A regulator gene can:

initiate or block the expression of another gene## CORRECT --> Regulator genes control the timing and duration of production of a variety of substances such as proteins in our bodies.

If there is a single pair of alleles that determine the number of toes for an animal species and homozygous dominant individuals have 8 toes, heterozygous ones have 7, and homozygous recessive ones have 6, the inheritance pattern would be referred to as:

intermediate expression. This hypothetical example would be an example of the intermediate expression of a trait. Apparently, this is rare. For most genes, it is expected that individuals with heterozygous genotypes will have phenotypes like homozygous dominant individuals.

The Hardy-Weinberg equilibrium equation (p²+ 2pq + q² = 1) allows geneticists to:

keep track of changes in genotype frequencies from generation to generation in a population

The most likely explanation for the fact that the Hawaiian Islands did not have any land mammals until humans arrived is that:

life on these islands has evolved largely independently of the rest of the world. Due to extreme geographic isolation, no land mammals ever reached Hawaii prior to the arrival of people. There were thousands of plant and animal species in Hawaii that existed nowhere else on our planet. The same was true of New Zealand.

If there is a family history of genetic disorders, knowing the gender of an unborn child can be important because:

male children are more likely to have X-linked traits show up in their phenotype

Somatic cells reproduce by ______________ , while sex cells reproduce by ______________ .

mitosis; meiosis

Population geneticists now usually think of evolution as being genetic changes in:

populations

What would a gene be called if it is inherited by both genders but expressed differently in the phenotype of men and women?

sex-controlled ## CORRECT --> An example of a sex-controlled genetic trait is gout. While both men and women can get it, men generally have more severe symptoms.

If the genes for a trait are inherited by both men and women but only show up in the phenotype of women, they are referred to as _____________ genes.

sex-limited Only one gender actually has sex-limited genes expressed in the phenotype, while both inherit them. The typical heavy male facial beard is an example of a trait whose inheritance follows this pattern.

The fossil record shows that:

some species are evolutionary transitions between major groups of organisms. As our knowledge has grown, it has become clear that what had been thought of as gaps in the fossil record were only due to incomplete data collection. Those gaps were, in fact, occupied by transitional forms.

Which of the following is an exception to Mendel's idea that genes are passed on unchanged from generation to generation?

stuttering alleles. Stuttering, or unstable, alleles structurally change from generation to generation. Segments of these rare genes are doubled each generation, resulting in an intensification of a trait. One form of muscular dystrophy apparently can follow this pattern.

Biologists have discovered that

the basic simple language of the DNA code is the same for all organisms. Surprisingly, the DNA code for making all parts of every organism is based on a simple language of combinations of 4 chemical bases. This suggests a common origin for all life forms on the planet.

Amniocentesis involves sampling:

the liquid immediately surrounding a fetus

Chromosomes are found in _____________________ of cells.

the nucleus. ## CORRECT --> However, keep in mind that the chromosomes only become visible when a cell begins to divide.

Amniocentesis, chorionic villi sampling, and alpha-feto protein sampling are done to determine:

whether or not the baby will be normal or abnormal

In science, a hypothesis that has been confirmed through numerous tests is known as:

If after repeated testing and peer review by other scientists in the same field, a hypothesis still holds up as a valid explanation for a group of facts, it becomes accepted as a theory.

Which of the following is a characteristic of anthropology?

It is concerned with both human biology and culture. and It is concerned with human variation, evolution, and adaptation.

Which of the following statements is true regarding karyotype analysis?

It is now an important medical tool used in predicting the likelihood that an unborn child will be normal.

Convincing scientific evidence now indicates that:

Laboratory experiments and careful genetic studies demonstrate that evolution is occurring now. In addition, it occurred in the past. The fossil record shows that living organisms, including people, evolved from earlier species.

Most genetic disorders are due to:

Most of the more than 5,000 known genetic disorders are at the DNA level. A karyotype analysis will not detect them since they are often the result of small mutations in what otherwise look like normal chromosomes.

If a woman is homozygous normal and her husband is heterozygous for a genetically inherited recessive disease and they decide to become parents, what is the probability that they will have a healthy child?

## CORRECT --> All of the children will be healthy since none of them can be homozygous recessive (aa). However, there will be a 50% chance at each birth that the children will be carriers (Aa). The remaining 50% will be homozygous dominant (AA).

Punnett squares are used by geneticists to determine the probability of different offspring genotypes. In the one shown below, what letter(s) belong in the lower right box?

## CORRECT --> All you have to do is carry over the letters in the row and column headings. The 2 empty boxes on the left will be Aa and the 2 on the right will be aa. In other words, 50% of the offspring are homozygous recessive (aa) and 50% are heterozygous (Aa).

When the genotype consists of a dominant and a recessive allele, the phenotype will be like _________________ allele.

## CORRECT --> The dominant allele masks the appearance of the recessive one. However, as you will see in the next section of this tutorial, there are some traits for which this simple rule of dominance does not apply.

All of the chromosomes in each normal human cell collectively have approximately __________ genes.

## CORRECT --> There has been some controversy in past years about the actual number of human genes. However, most researchers now agree that about 20,000-25,000 is a fairly good estimate.

If two parents are heterozygous for a genetically inherited dominant trait, what is the probability that they will have a child together who has this trait in his or her phenotype?

## CORRECT --> There is a 50% chance that the children will be heterozygous (Aa) and a 25% chance that they will be homozygous dominant (AA). Children with either of these genotypes will have this trait expressed in their phenotypes.

If two people who are both carriers for a genetically inherited fatal recessive disease decide to become parents, what will be the odds that their children will also be carriers?

## CORRECT --> There will be a 50% chance (2 out of 4) of having a carrier (Aa) child. Similarly, each time there will be a 25% chance of having an offspring who will inherit the disease (aa) and die.

If two parents are homozygous for a genetically inherited recessive trait, what is the probability that they will have a child who does not have this trait in his or her phenotype?

0% Since both parents are homozygous recessive (aa), all of their children will be as well. As a result, none of them will be free of this recessive trait in their phenotypes.

Amniocentesis usually is not done before the __________ week after conception.

15th-16th

Population genetics and the synthetic theory of evolution were developed mostly in the _____ century.

20th

Normal humans have __________ pairs of autosomes and ___________ pairs of sex chromosomes.

22 and 1 ## CORRECT --> Humans normally inherit 22 autosomes and 1 sex chromosome from each parent. In total, we have 46 chromosomes in somatic cells--22 pairs of autosomes and 1 pair of sex chromosomes.

Results of amniocentesis tests usually come back from the laboratory in:

3-4 weeks

When there are three or more alleles of a specific gene, it is referred to as a:

A multiple-allele series is one in which there are 3 or more alleles but only 1 is inherited from each parent. The ABO blood type system and the HLA body tissue recognition/rejection system are examples. Apparently, multiple-allele series are common.

The scientific method of inquiry involves which of the following steps?

After hypotheses have been shown to be correct as a result of numerous tests, they must also pass rigorous peer review by other scientists in the same field.

Which of the following is not one of the 4 main fields of anthropology?

Cartography is a field of geography, not anthropology. Cartographers make maps.

What do anthropologists mean when they refer to the concept of "integration" in regards to cultures?

All aspects of a culture are interrelated. Understanding any cultural trait requires knowing how it impacts and is in turn impacted by others. Likewise, human biological traits do not function in isolation. To understand them, it is necessary to grasp how they are interrelated with others.

An allele is:

An allele is one of two or more alternate forms of a gene. If an individual is homozygous (YY or GG) for a trait, it has inherited the same allele from both parents. If it is heterozygous (YG), it has inherited different alleles for the trait.

Which of the following is true about anthropology?

Anthropology as an academic discipline is comparatively young. Its roots go back to the intellectual Enlightenment of the 18th and early 19th centuries in Europe and North America. Curiosity about strange people and customs in far off parts of the world is what primarily motivated the early anthropologists. By the late 19th century, anthropology finally became a separate academic discipline in universities.

Which field of anthropology is primarily concerned with the non-cultural aspects of humans and near-humans?

Biological anthropologists mostly research the biological aspects of humans and non-human primates. However, they understand that it is also necessary to take into consideration the culture of the people and other primates that they study.

Some people have AB blood types for the ABO blood system. They have all of the characteristics of both type A and type B blood--they are not a blend of them. The inheritance pattern responsible for this is referred to as:

Codominance. ## CORRECT --> Codominant traits are ones in which both alleles are expressed when the phenotype is heterozygous. In the case of the ABO blood type system, A and B are codominant. They are also both completely dominant over O.

Which of the following statements is true regarding biological evolution?

Evolution is genetic change in a population from generation to generation.

Inherent in the holistic approach to learning about humans is the realization that:

People cannot be understood by studying either their biological makeup or their cultural background alone. It is necessary to take into consideration both genetically inherited and learned traits in trying to explain how we have become the people we are.

Phenotype refers to the ______________________ of an individual.

Phenotype is the observable characteristics, including physical appearance. It results from the genotype and environmental influences. A phenotype includes not only easily measured traits like hair color but also less apparent ones such as blood type.

In the diagram below, what accounts for the green pea seed in the f2 generation?

Since the recessive allele is green, only plants that are homozygous green for this trait will have a green phenotype. The homozygous yellow and the heterozygous ones will all be yellow.

The development of masculine physical characteristics is most affected by the inheritance of:

The SRY (or sex determining region Y) gene is necessary for an XY individual to develop male physical characteristics. Without it, female traits develop instead.

Culture is

The ability to create culture has been an incredibly useful tool for adapting to our environments and spreading over the globe. It has also made it possible for the human population to continue growing explosively.

Which of the following statements is true of the Hardy-Weinberg equation (p² + 2pq + q²= 1)?

The equation allows you to discover the genotype frequencies if you know the phenotype frequencies. The tremendous value of the Hardy-Weinberg equation is that it allows us to discover what a population`s genotype frequencies are for a trait despite the fact that we can only observe the phenotypes.

Which of the following statements is true about cells?

The nucleus is within the nuclear membrane which is surrounded by the cytoplasm. ## CORRECT --> The nuclear membrane acts as a selectively permeable barrier. That is to say, it allows some important substances to cross over while keeping the contents of the nucleus from spilling out into the cytoplasm.

Punnett squares can be used to predict the probability of:

The probability of inheriting almost any trait can be predicted if the genetic makeup of the parents is known. The likelihood of both good and bad traits showing up in the phenotype can be determined using Punnett squares.

Genes are segments of DNA molecules

The units of inheritance that we refer to as genes actually are long segments of codons in DNA molecules. Each DNA molecule has many gene segments.

Which of the following statements about living cells is false?

They are found in all animals but not in all plants. ## CORRECT --> All living things, including plants are made up of cells. However, comparatively simple things such as viruses do not have most of the components of cells nor are they technically living in the same sense as plants and animals.

Which of the following statements is true about the chromosomes of different plant and animal species?

They may differ in number, shape, and size. ## CORRECT --> This fact provides a useful tool for biologists in distinguishing between species. For instance, humans have 46 chromosomes, while chimpanzees have 48. This number difference is one indication that we are not the same species.

The idea that different pairs of alleles are passed to offspring independently is Mendel's principle of:

This is a definition of his principle of independent assortment. Stated in other words, the genes that determine a trait assort independently of the genes for other traits. As a result, new combinations of genes, present in neither parent, are possible.

The idea that for any particular trait, the pair of alleles of each parent separate and only one allele from each parent passes to an offspring is Mendel's principle of:

This is the definition of the principle of segregation. Stated in other words, genes occur in pairs and during the process of sex cell production, the members of each pair separate so that each sperm and ovum cell receives one member of each pair.

"Synthetic theory of evolution" refers to:

a combination of Charles Darwin's concept of natural selection along with evolutionary theories developed in the 20th century by population geneticists and molecular biologists

Gregor Mendel was:

a little known Central European monk. He worked in virtual obscurity during the mid 19th century. Unfortunately, Charles Darwin did not know of Mendel`s work. He was one of the few scientists of that time who might have understood and appreciated Mendel`s huge contribution to science.

A chorion is:

a membrane that develops around an embryo and contributes to the formation of the placenta

The likelihood of a child being born with a major genetic defect, such as mental retardation, can often be detected by sampling:

cells from the embryo or fetus

Which of the following procedures usually involves inserting a small flexible plastic tube through the vagina into the uterus?

chorionic villi sampling

Amniocentesis can be used to determine whether or not an unborn child will:

down syndrom

"The sum total of the genetically inherited changes in the individuals who are members of a population" is a description of:

evolution

Angelman syndrome is a rare form of mental retardation that can be more or less severe depending on the gender of the parent from whom it is inherited. This unusual kind of inheritance pattern is known as:

genome imprinting ## CORRECT --> When genes have a different effect depending on the gender of the parent from whom they were inherited, it is referred to as genome imprinting. Diabetes, psoriasis, and Prader-Willi syndrome are other examples of this phenomenon.

If there were a gene for intelligence and the effect of that gene was altered by the inheritance of another gene, the latter gene would be referred to as a:

modifying gene ## CORRECT --> Modifying genes alter the effect of companion genes in the phenotype of an individual. A real life example is a gene that modifies the effect of a dominant cataract allele.

A chromatid is:

one of the strands or arms of a chromosome. ## CORRECT --> When a chromosome becomes visible just before cell replication, it has two or more chromatids that come together at a centromere. At other times, chromosomes are long, thin, thread-like structures that appear as an essentially undifferentiated mass.

The fact that monozygotic twins do not have identical phenotypes despite the fact that they may look alike is an indication that:

phenotypes are a result of both the genotype and environmental influences. While monozygotic twins are identical in genetic makeup, what happens to them as individuals after conception and birth can alter their phenotypes.

A karyotype is a:

picture of an individual's chromosomes arranged in a standardized way. ## CORRECT --> Karyotypes allow us to quickly see if an individual has any gross chromosomal abnormalities. For instance, this technique can be used to identify the genetically inherited condition known as Down`s syndrome.

If medical researchers discovered that there is a single human gene responsible for all of the various forms of physical deterioration commonly associated with diabetes, it would be referred to as:

pleiotropy## CORRECT --> Pleiotropy is a genetic inheritance pattern in which a single gene causes or affects an entire series of traits.