Phys Anth

Sex linked traits

(X); A trait associated with a gene that is carried only by one parent. More common in males.

Turner syndrome

(XO); A chromosomal disorder in which a female is born with only one X chromosome (45 chromosomes w/ only 1 sex chromosome).

Super females

(xxx, xxxx); also none as trisomy X is characterized by the presence of an extra X chromosome in each female cell, infertile and cognitive issues.

Kleinfelter

(xxy, xxxy); A genetic condition in which a male is born with an extra copy of the X chromosome.

Super males

(xyy, xyyyy); The phenotypic manifestation of an extra Y chromosome, infertile and cognitive issues.

The PTC-tasting locus has two alleles, T and t, where T is dominant and is the tasting allele. If the genotype frequencies are TT = 0.49, Tt =.42, and tt = 0.09, what proportion of this population are tasters?

0.91

Each amino acid is coded for by _______ chemical bases.

3

The DNA molecule is made up of ____ chemical bases.

4

Sex chromosomes

A chromosome involved with determining the sex of an organism, typically one of two kinds.

Biological Species Concept

A definition of species that focuses on reproductive capabilities whereby organisms from different populations are considered to be in the same species if they naturally interbreed and produce fertile offspring.

Breeding populations

A group of organisms that tend to choose mates form within the group

Achondroplasia

A hereditary condition in which the growth of long bones by ossification of cartilage is compromised, resulting in short limbs and occasional small skull size.

Hardy-Weinberg-Castle Equilibrium

A mathematical statement whereby, in the absence of non random mating and evolutionary forces, genotype and allele frequencies will remain the same from one generation to the next. Equation: (P^2 + 2pq + q^2 = 1); Assumptions: no mutation, random mating, no gene flow, very large population size, and no natural selection.

Natural selection

A mechanism for evolutionary change favoring the survival and reproduction of some organisms over others because of their biological characteristics.

Mutation

A mechanism for evolutionary change resulting from a random change in the genetic code the ultimate source of all genetic variation. Mutations must occur in sex cells to cause evolutionary change.

Gene flow

A mechanism for evolutionary change resulting from the movement of genes from one population to another.

Genetic drift

A mechanism for evolutionary change resulting from the random fluctuations of gene frequencies from one generation to the next.

Point mutation

A mistake in the DNA. Occurs when an enzyme mistakenly replaces a correct nucleotide instead of an incorrectly paired base.

Tay Sachs Disease

A rare, inherited disorder that destroys nerve cells in the brain and spinal cord.

Exons

A section of DNA that codes for the amino acids that make up proteins. It is contrasted with an intron.

Introns

A section of DNA that does NOT code for the amino acids that make up proteins. It is contracted with an exon.

Derived Traits

A trait that has changed from an ancestral state. The large human brain is a derived trait relative to the common ancestor of humans and apes.

Primitive Traits

A trait that has not changed from an ancestral trait

Founder effect

A type of genetic drift caused by the formation of a new population by a small number of individuals.

Assume two alleles, A and a, at a given locus. If the frequency of the A allele is 0.6 and the frequency of the a allele is 0.4, the expected genotype frequencies are:

AA = 0.36, Aa = 0.48, aa = 0.16

Autosomal chromosomes

An autosome is any of the numbered chromosomes, as opposed to the sex chromosomes. Humans have 22 pairs of autosomes and one pair of sex chromosomes (the X chromosome and the Y chromosome).

You often hear arguments about whether evolution is a fact or a theory. Which is it?

Both

Homologous

Chromosomal pairing at meiosis and having the same structural features and pattern of genes. Homologous chromosomes are chromosome pairs (one from each parent) that are similar in length, gene position, and centromere location. The position of the genes on each homologous chromosome is the same, however the genes may contain different alleles.

Charles Darwin

Darwin's revolutionary insights: 1) All life is related and can be diagrammed as Tree of Life 2) Populations vary, parents vary, and this variation is inherited. This is what makes evolution possible 3) Some variation is more advantageous in a particular environment, and these individuals out-survive and out-reproduce other individuals. 4) Through time, this advantageous variation dominates and creates a new species slightly, although definitely, different

Genotype Ratio

Describes the number of times a Genotype would appear in the offspring after a test cross. Ex: TT Tt Tt tt Genotype ratio 1:2:1 (TT= 25% Tt= 50% tt = 25%)

You visit a random mating population and find that the observed genotype frequencies are not what would be expected under Hardy-Weinberg equilibrium. What does this suggest?

Evolution has occurred.

Logical deductions of natural selection

Fact 1. More are born than needed to replace the parents Fact 2. natural populations are stable or grow very slowly. Deduction 1: There must be competition to survive Fact 3. There is variation in the parents in the population Fact 4. these variations are inherited by the offspring Deduction 2: some variations are better suited for the environment Fact 5. species reflect this adaptation. Deduction 3: species have an origin and an end

Species are always defined by reproductive isolation.

False

The fact that humans have five digits is not an example of a primitve trait.

False

The following are correct DNA and messenger RNA sequences ACG TAA CTG GCC DNA UGC AUU GUG CGG MRNA

False

Law of Unit Inheritance

Genes come in pairs and are inherited as distinct units or discrete particles, one from each parent (either dominant or recessive); this denies blending inheritance.

Imagine you see the frequency of a harmful allele increase slightly over time in an isolated population. What could be responsible for this contradictory observation?

Genetic drift

___________ first demonstrated the principles of genetic inheritance.

Gregor Mendel

Bottleneck effect

Happens when a group experiences a sizable population decrease (such as an earthquake) which will impact the genetic frequencies of future generations.

Homozygote

Having two identical alleles of a particular gene or genes and so breeding true for the corresponding characteristic. Example: If you inherit the same allele for a trait from both your parents, your genotype is homozygous for the trait. So BB or bb

Jean Baptiste Chevalier de Lamarck

He developed the concept of the Inheritance of Acquired Characteristics. He posited that changes in the environment created needs in organisms, which altered behavior, which in turn caused bodily changes. He believed that changes an organism underwent during life were inherited by the organism's offspring. In this way organisms slowly changed through time to become well adapted to their environments.

Alfred Wallace

He is best known for independently conceiving the theory of evolution through natural selection; his paper on the subject was jointly published with some of Charles Darwin's writings in 1858. This prompted Darwin to publish his own ideas in On the Origin of Species.

Gregor Mendel

His experiments resulted in the formulation of two generalizations that later became known as the laws of heredity. His observations also led him to coin two terms still used in present-day genetics: dominance, for a trait that shows up in an offspring; and recessiveness, for a trait masked by a dominant gene. He was able to establish the mathematical basis of the inheritance of characters. His experiments were with pea plants.

_________ genes encode a sequence of 60 amino acids that regulate embryonic development.

Homeobox

Inheritance of Acquired Characteristics

Hypothesis that physiological changes acquired over the life of an organism (such as the enlargement of muscle through repeated use) may be transmitted to offspring.

Convergent evolution

Independent evolution of a trait in rather distinct evolutionary lines. The development of flight in birds and certain insects is an example of convergent evolution.

__________ believed that the environment affected the future evolution of organisms through differences in the use and disuse of body parts.

Lamarck

Laws of Inheritance

Law of Segregation and Law of independent assortment

Macroevolution

Long-term evolutionary change. The study of macroevolution focuses on biological evolution over many generations and on the origin of higher taxonomic categories, such as species.

Inbreeding

Mating between biologically related individuals.

Since most parents of achondroplastic dwarfs are normal, and since the achondroplastic allele is dominant, this means that

Most dwarfs are the result of a mutation.

Where is DNA found in a cell?

Mostly in the nucleus, with a small amount in the mitochondria

Mechanisms of Evolution

Mutation, Gene Flow, Natural Selection, and Genetic Drift.

Assume the frequency of an allele has changed from 0.30 to 0.58 in a single generation in the population you are studying. This change is not likely to have been caused by mutation. Why?

Mutations occur less often than this.

Species

Often defined as a group of individuals that actually or potentially interbreed in nature. In this sense, a species is the biggest gene pool possible under natural conditions.

Non-random mating

Patterns of mate choice that influence the distributions of genotype and phenotype frequencies.

Positive/negative assertive mating

Positive: unusual propensity for similar phenotypes to mate. Negative: unusual tendency for unlike phenotypes to mate.

Protein synthesis

Process of creating protein molecules with the help of RNA (Know this process! pg 38)

DNA regulates the process of protein synthesis with the help of

RNA

Holistic

Refers to the viewpoint that all aspects of existence are interrelated and important in understanding human variation and evolution

Given that humans and apes share over 98 percent of their genetic material, it seems likely that their anatomical differences involve differences in __________ genes.

Regulatory

Microevolution

Short term evolutionary change. The study of microevolution focuses on changes in allele frequencies from generation to the next.

Homology

Similarity due to descent from a common ancestor

Homoplasy

Similarity due to independent evolution

Law of Segregation

States that sex cells contain one of each pair of alleles. This demonstrates that both parents contribute equally to the production of offspring.

Law of Independent Assortment

States that the segregation of any pair of chromosomes does not influence the segregation of any other pair of chromosomes. In other words, chromosomes from different pairs are inherited independently.

In DNA, the base A pairs with the base

T

Alleles

The alternative form of a gene or DNA sequence that occurs at a given locus. Some loci have only one allele, some have two, and some have alternative forms. Alleles occur in pairs, one on each chromosome.

Thomas Robert Malthus

The central theme of Malthus' work was that population growth would always overpower food supply growth, creating perpetual states of hunger, disease, and struggle. The natural, ever-present struggle for survival caught the attention of Darwin, and he extended Malthus' principle to the evolutionary scheme.

Gene pool

The collective genetic information contained within a population of sexually reproducing organisms.

Meiosis

The creation of sex cells by replication of chromosomes followed by cell division. Each sex cell contains 50% of an individual's chromosomes (one from each pair).

Adaptive Radiation

The formation of many new species following the availability of new environments or the development of a new adaptation.

Cladogenesis

The formation of one of more new species from another over time.

Which of the following statements regarding the sickle cell allele is true?

The frequency of the sickle cell allele is higher in malarial regions than in non-malarial regions.

Genotype

The genetic endowment of an individual from the two alleles present at a given locus.

Reproductive Isolation

The genetic isolation of populations that may render them incapable of producing fertile offspring.

DNA

The molecule that provides the genetic code for biological structures and the means to translate this code.

Phenotype

The observable appearance of a given genotype in the organism. The phenotype is determined by the relationship of the two alleles at a given locus, the number of loci, and often environmental influences as well.

Uniformitarianism

The observation that the geologic processes that operate in the world today also operated in the past

Mitosis

The process of replication of chromosomes in body cells. Each cell produces two identical copies.

Adaptation

The process of successful interaction between a population and an environment. Cultural or biological traits that offer an advantage in a given environment are adaptations.

Taxonomic classification

The science of describing and classifying organisms.

Anthropology

The science that investigates human biological and cultural variation and evolution

Which of the following is a characteristic of genetic drift?

The smaller the population, the greater its effect.

Anagenesis

The transformation of a single species over time.

Evolution

The transformation of species of organic life over time.

The ABO blood group has three alleles (A, B, O) where A and B are codominant and O is recessive. How can a woman with type A blood and a man with type B blood have a child with type O blood?

The woman must have genotype AO and the man must have genotype BO.

Aneuploidy

The wrong chromosome count or abnormal chromosome number (because spindle fibers breaking during meiosis).

Simple Mendelian Traits

These are traits with 2 phenotypes and are biologically determined through genetics. Examples include: widow's peak, chin cleft and dimples.

Complex Traits

Traits that are the result of numerous factors, both genetic and environmental; they also form a continuous distribution.

A major discovery with the human genome and decoding other genomes is that life shares a lot of genes and that relatively few are needed for humans

True

Convergent evolution is when have the independent evolution of similar traits in distantly related species, such as fins on sharks and whales.

True

Darwin and Alfred Russel Wallace share credit for independent invention of the mechanism of natural selection, although Darwin had developed it first.

True

Genetic drift will probably be involved in speciation once gene flow is stopped.

True

Natural selection is a force of evolution that often ultimately creates a new species.

True

There are two alleles for the PTC-tasting locus in humans: T, which codes for tasting, and t, which codes for non-tasting. T is dominant and t is recessive. Imagine two parents that are tasters have a child that is a non-taster. Given this information, you know that the genotypes of the parents had to have been

Tt and Tt.

The view that the stratigraphy is the result of natural geological process that were at work in the past and are still at work today is _________.

Uniformitarianism

Addition

When a base pair is added to the sequence.

Deletion

When a base pair is deleted or taken away from the sequence.

Exogamy

When one marries someone OUTSIDE one's own social group or community.

Endogamy

When one marries someone WITHIN one's own social group or community.

Frameshift

When there is either an addition or deletion of one or two base pairs (which then puts the next region out of proper reading frame).

Lineage effect

When villages grow, fission occurs. This results in a type of non random splitting that increases the effects of genetic drift.

Gene

a DNA sequence that codes for a functional polypeptide or RNA product.

The alternative forms of a gene found at a given locus are known as

alleles.

Prior to the development of evolutionary thinking, the dominant view of biological variation focused on

an unchanging natural world.

A polymorphism is defined as a genetic trait where there

are at least two alleles having frequencies greater than 0.01

One difference between anthropology and many other social sciences, such as sociology, is that anthropology is concerned with human _____________ as well as human behavior.

biology

Alleles are _________ if both of their effects are shown in the phenotype.

codominant

Genetic drift acts to __________ variation within populations and _________ variation between populations.

decrease / increase

DNA consists of coding sections (known as ________) and non-coding sections (known as _________).

exons / introns

The probability of survival and reproduction of an organism is known as its

fitness

The relationship between sickle cell allele frequencies and malaria provides an excellent example of selection _____ ___ ___________

for the heterozygote.

Linnaeus

formalized the modern system of naming organisms called binomial nomenclature. He is known by the epithet "father of modern taxonomy".

Heritability is a measure of the proportion of total variation that is related to ___________ variation.

genetic

The total DNA sequence of an organism is known as its

genome

The shape of a DNA molecule is a

helix

Natural selection can act to __________ variation between populations.

increase or decrease

Assume a locus where there is an occasional mutation from the A allele to the B allele. Under these circumstances, the frequency of the B allele will

increase over time.

Some of those who disagree with evolutionary theory claim that some biological structures are too complex to have evolved naturally, a view known as

intelligent design creationism.

Cultural Relativism

is the idea that a person's beliefs, values, and practices should be understood based on that person's own culture, rather than be judged against the criteria of another.

Chromosomes

long strands of DNA sequences

Darwin's development of natural selection was influenced by the writings of the economist Thomas Malthus, who noted that

many organisms will not survive to adulthood

Hemophilia is caused by a recessive allele found on the X chromosome. As such, hemophilia will be

more common in men than women.

Mutations

must occur in sex cells to have an evolutionary impact.

The study of evolution of the peppered moth provides an excellent example of

natural selection.

Phenotype Ratio

pertains to the relative number of offspring manifesting a particular trait or combination of traits. It can be determined by doing a test cross and identifying the frequency of a trait or trait combinations that will be expressed based on the genotypes of the offspring. Ex: given that T=t & t= short TT Tt Tt tt Phenotype ratio is 3:1 (75% tall 25%) short.

Traits that are due, in part, to multiple loci are known as _________ traits.

polygenic

Each parent contributes one allele at each locus to his or her offspring. This is known as Mendel's Law of

segregation

Natural selection often removes one allele and increases the frequency of another allele. _____________________, however, can result in a balance of allele frequencies without removing any alleles from the population.

selection for the heterozygote

Babies born too small or too large are less likely to survive than those born closer to an average weight. This is an example of ___________ selection.

stabilizing

Gene frequency

the ratio of a particular allele to the total of all other alleles of the same gene in a given population.

Hardy-Weinberg equilibrium states that

under certain conditions, allele frequencies will remain constant over time.

Selection against a recessive homozygote will

will gradually decrease the frequency of the recessive allele.