BIOL 189: Lab 11

Explain the different types of fossils that can occur: impressions vs bones vs organism trapped in amber

-Impressions: soft mud where dead organism is buried hardens into rock around organism, space has same shape as exterior of organism -Bones: teeth/bones do not decay rapidly, minerals in waster deposited w/in spaces in bone as it breaks down -Trapped: organism are largely preserved in original state

bionomial nomenclature

-a system to specify an organism by its genus and species. every organism is given a scientific name consisting of two parts: its genus and species names -2 word naming system: Genus + Species, refers to a species by their Genus + Species classification, Capitalize Genus name + italicize both names

What is fossil formation?

-organism dies, if no fossil is formed, organism was eaten/broken down-If organism is preserved quickly, -fossil can be preserved through rapid freezing, dessication (dried out), or burial in amber (hardened tree sap) -rapid burial in sediment layers (mud/volcanic eruption), protects body from rapid decay

Genotype vs. Phenotype

An organism's genotype is the set of genes that it carries. An organism's phenotype is all of its observable characteristics

Agglutination in the well

Antigen Present

Codominance

Codominance essentially means that no allele can block or mask the expression of the other allele. For example, A and B are dominant in a sense since B is dominant to O and A is dominant to O. When one of the inherited alleles is A and the other is B, the genotype is heterozygous and the blood type is AB.

Based on allele frequencies, how could you determine whether or not a population has evolved compared to the previous population?

If starting population is different from observed, it means population is evolving

How can a pedigree tell you if it is a recessive or a dominant trait?

If the trait is dominant, one of the parents must have the trait. Dominant traits will not skip a generation. If the trait is recessive, neither parent is required to have the trait since they can be heterozygous.

artificial selection

In artificial selection, a human chooses which individuals get to breed, in an effort to select for one or more desirable traits.

What are two ways to define evolution?

In its broadest sense, one way to define evolution is "descent with modification." On the scale of a population's gene pool, evolution is a change in allele frequencies in a population over time

natural selection

In natural selection, the environment might select for the same traits, provided that those traits promote reproductive success.

incomplete dominance

Incomplete dominance is when a dominant allele, or form of a gene, does not completely mask the effects of a recessive allele, and the organism's resulting physical appearance shows a blending of both alleles.

Law of Segregation

Mendel's law that states that the pairs of homologous chromosomes separate in meiosis so that only one chromosome from each pair is present in each gamete (Anaphase 1 and 2 in Meiosis)

law of independent assortment

Mendel's second law, stating that allele pairs separate from one another during gamete formation (happens in Metaphase 1 in Meiosis 1)

Microevolution vs. Macroevolution

Microevolution happens on a small scale (within a single population), while macroevolution happens on a scale that transcends the boundaries of a single species. Despite their differences, evolution at both of these levels relies on the same, established mechanisms of evolutionary change: mutation.

Antibodies

Proteins that attach to antigens, keeping them from harming the body

Widows Peak

Widow's peak: Dominant (W) Straight for the headline : Recessive (w)

What is a dihybrid cross?

a cross that examines the inheritance of two different traits

complete dominance

a relationship in which one allele is completely dominant over another

antigen

a toxin or other foreign substance that induces an immune response in the body, especially the production of antibodies.

Scientists use relative dating and absolute dating to

estimate when a fossil organism lived.

2pq

heterozygous p2 + 2pq + q2 = 1.0

p2

homozygous dominant p2 + 2pq + q2 = 1.0

q2

homozygous recessive p2 + 2pq + q2 = 1.0

When allele and genotype frequencies are not changing between generations, the population is said to be

in Hardy-Weinberg equilibrium.

Hardy-Weinberg equation

p^2 + 2pq + q^2 = 1

How do you read a pedigree chart?

picture--->

Dominant Pedigree

shows an autosomal dominant trait inheritance; the trait is seen in every generation

The study of classification is called ______, which incorporates both taxonomy and phylogenetics.

systematics

What was the purpose of the experiment with the red and white chips?

to determine allele frequencies over several generations. The assumption that the population is in the equilibrium of calculating the allele frequencies and recording the genotypes Red: dominant allele White: recessive allele

What was the purpose of the corn experiment?

to investigate the inheritance of patterns of color and sweetness in Indian corn. The kernal color (purple or yellow) in Indian corn is controlled by the alleles P (purple) and p (yellow), with purple (P) being dominant. Carbohydrate content (starchy or sweet) is controlled by the alleles S (starchy) and s (sweet), with starchy (S) being dominant. Sweet kernels can be distinguished from starchy kernels because sweet kernels are wrinkled when they are dry, and starchy kernels are smooth

autosomal recessive

two copies of an abnormal gene must be present in order for the disease or trait to develop

How are chromosomes, genes, and alleles related?

Alleles are different forms of same gene. Genes are linearly arranged on chromosomes. Chromosomes contain genetic material of cell i.e. DNA.

homozygous vs heterozygous alleles

*homozygous* - organism containing pair of the same alleles for particular trait (bb) *heterozygous* - organism containing 2 different alleles for a trait (Bb)

how do you calculate allele frequencies?

-% of a particular allele out of all alleles in a population, to determine this take a type of allele and divide it by the total number of alleles that make up a specific population

How can you determine if a disease is autosomal l or sex-linked on a pedigree? How can you determine if a disease is dominant or recessive based on a pedigree?

-A disease can be autosomal on a pedigree if both males and females are seen expressing the phenotype, and if there are no half-filled circles. Autosomal dominant disorder needs one allele of the disease to express that trait. They are not sex-linked they appear in equal proportion. There are "no carriers" -If sex-linked, there are individuals shown as carriers, or it occurs based on XX or XY, the sex chromosomes. -If the trait is dominant, one of the parents must have the trait. Dominant traits will not skip a generation. If the trait is recessive, neither parent is required to have the trait since they can be heterozygous.

Explain Hardy-Weinberg Equilibrium to me. What conditions have to be met for this to occur?

-Allele frequencies + genotype frequencies do not change from one generation to the next due to five conditions: 1. Natural Selection does not occur. 2. Mutations do not occur (no new alleles). 3. Population is infinitely large. 4. Individuals mate randomly. 5. Individuals do not migrate

Rank the following taxonomic groups into a hierarchy, from the most inclusive group at the top to the most specific group at the bottom.

1. domain 2. kingdom 3. phylum 4. class 5. order 6. family

What is a monohybrid cross?

A cross between two individuals, both heterozygous for one gene

What is a fossil?

A fossil is the preserved remains or imprint in a rock of a plant or animal, usually one that lived a long time ago. Many of the fossils discovered so far are ancestors of organisms living today, while some fossils are the remains of organisms that still exist.

Genetic Trait: (Bent little finger)

Bent finger: Dominant (C) Straight finger:Recessive (c)

Similarities in antibodies and antigens

Both antigen and antibody are involved in triggering an immune response. Both antigens and antibodies are involved in destroying the foreign substances.

Curly Hair

Curly Hair: Dominant "A" Straight Hair: Recessive "a"

Understand beak variations in Darwin's beaks and how it is significant in terms of survival

Darwin's Finches: Darwin observed that beak shape varies among finch species. He postulated that the beak of an ancestral species had adapted over time to equip the finches to acquire different food sources.

Dimpled Cheeks

Dimples: Dominant "D" Absence of dimples: recessive "d"

hierarchial classification system

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

Dominant Trait vs Recessive Trait

Dominant traits are always expressed when the connected allele is dominant, even if only one copy of the dominant trait exists. Recessive traits are expressed only if both the connected alleles are recessive.

Freckles

Freckles: Z Dominant non: z recessive

Free Earlobe

Free Earlobe: Dominat (E) Attached Earlobes: Recessive (e)

Distinguish between relative and absolute dating of fossils

Relative dating of fossils is based upon the position of the rock layer in which a fossil is found. It allows a paleontologist to decide whether one fossil is older or younger than another. Absolute dating techniques, including radiometric dating, assign a range of dates that tell when a fossil formed

Taxonomy

Taxonomy is the method we use to identify and group organisms based on their similar morphological (physical) characteristics. It is founded on the concept that morphological similarities descend from a common evolutionary ancestor.

What is the study of fossils called?

The study of fossils is called paleontology. The total number of fossils and their placement within rocks is known as the fossil record.

Mendelian traits

These are the traits that are passed from parents to offspring by dominant and recessive alleles of a gene, determined by all the Laws of Inheritance proposed by Mendel.

Tongue rolling

Tongue Rolling: Dominant (R) Non-rolling- Recessive (r)

recessive pedigree

Two unaffected parents result in an affected child