BSC 101 Exam 2- Illinois State University

ethical considerations of bioprospecting

Microevolution

the change in allele frequencies that occur over time within a population. Due to mutation, selection, gene flow, and genetic drift.

Macroevolution

major evolutionary change.

Natural Selection

the process whereby organisms better adapted to their environment tend to survive and produce more offspring. For example, treefrogs are sometimes eaten by snakes and birds.

Mutation

A Mutation occurs when a DNA gene is damaged or changed in such a way as to alter the genetic message carried by that gene. For example, sickle cell anemia is caused by a substitution in the beta-hemoglobin gene, which alters a single amino acid in the protein produced.

Genetic Drift

he change in the frequency of an existing gene variant (allele) in a population due to random sampling of organisms. For example, population of rabbits can have brown fur and white fur with brown fur being the dominant allele. By random chance, the offspring may all be brown and this could reduce or eliminate the allele for white fur.

Gene Flow

the movement and exchange of genes or alleles from one population of species to another. For example, a bee carrying pollen from one flower population to another, or a caribou from one herd mating with members of another herd.

Allele

different versions of genes

Gene

DNA-encoded instructions for a particular trait

Genotype

Genetic make-up for one gene, consisting of both alleles

Phenotype

observable traits expressed by an organism

Allele Frequencies

a measure of the relative frequency of an allele on a genetic locus in a population.

Allopatric Speciation

1. Populations become geographically separated.

2. Gene flow is interrupted

3. Genetic and phenotypic changes accumulate.

4. Reproduction becomes less and less likely, and eventually, impossible.

Sympatric

Occurs when the two groups of one species that ends up diverging are not geographically isolated from each other.

Assembling Phylogenies

To build a phylogenetic tree such as the one to the right, biologists collect data about the characters of each organism they are interested in. Characters are heritable traits that can be compared across organisms, such as physical characteristics (morphology), genetic sequences, and behavioral traits.

Lines of Evidence supporting Evolution

1. Fossil evidence

*transitional forms

2. Morphological homology

-Tetrapod forearm example

-Vestigial traits

3. Molecular homology

4. Distribution of organisms/fossil in time and space

5. Chronology

Describe DNA structure

DNA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C).

"The Central Dogma"

process of DNA to RNA to Protein.

Transcription: copying of DNA code to RNA, one nucleotide at a time so it is complementary to the DNA

Translation: RNA gets translated into protein

>every 3 RNA bases codes for an amino acid

implications of genetic code being universal

The information is contained in the specific sequence of nucleotides, and the genetic code is the way in which an organism uses the order of nucleotides to direct its development. It's the same among plants, animals, bacteria and fungi -- that's why it's called "universal

Gene expression

the process of turning on a gene to produce RNA and protein

-all cells have the same complete genome

>each cell controls which genes in the genome are expressed and when

Gel electrophoresis

separates DNA strands based on length

ex: paternity tests

Polymerase Chain Reaction (PCR)

takes a few copies of DNA and makes millions of copies

ex: used when only one or a few copies of DNA are available for DNA analysis

Molecular Cloning

short strands of DNA are cloned

Reproductive Cloning

used to make a clone or copy of entire multicellular organism

ex: dolly (first born cloned sheep)

Gene Therapy

used to treat genetic disorders resulting in a missing or dysfunctional gene/protein

Production of Vaccines, Antibiotics, Hormones

use molecular cloning to produce a gene product such as: H1N1 flu vaccine, penicillin and many other antibiotics, human insulin, human growth hormone

Transgenic Plants & Animals

Transgenic plants are plants that have been genetically engineered, a breeding approach that uses recombinant DNA techniques to create plants with new characteristics.

Commensalism

interaction between two species where one benefits and the other does not benefit or is not harmed

ex: bird in tree

Parasitism

when one species benefits, and other is negatively affected

ex: brown bird lays eggs in other bird's nest, then other bird takes care of baby

Mutualism

mutually benefits both parties.

ex: The oxpecker is a bird that has a mutualistic relationship with a rhino or a zebra.

Predation

predator, when one feeds off other

ex: bear eats fish

examples of keystone species

a species on which other species in an ecosystem largely depend, such that if it were removed the ecosystem would change drastically.

ex: wolves in Yellowstone

energy flow

food chains

what limits the length of food chains?

energy limits the length of food chains. Energy is lost at each level.

importance of photosynthesis for ecosystems

Photosynthesis is the process by which all energy in the ecosystem is made.

biomagnification

the concentration of toxins in an organism as a result of its ingesting other plants or animals in which the toxins are more widely disbursed.

ex: mercury in a snapping turtle

rates of human population growth throughout history

increasing significantly as time goes on

consequences of exponential human population growth

-insufficient resources

-unequal distribution of resources

-starvation

-rapid spread of disease

-less effective sanitation

-declining life expectancy

plausible solutions to slow the rate of human population growth

reduce carbon footprint, spread awareness, etc

water cycle

evaporation, sublimation, condensation, precipitation, subsurface flow, surface runoff, ice/snowmelt, stream flow

carbon cycle

short term cycle: through photosynthesis and respiration, animals eat the plants, take in carbon, die and goes back into the air

long term cycle: carbon that is in soil and fossilized carbon, through air gas sea exchange it goes through

greenhouse effect

heat/light/radiation travels from sun to earth, a lot is radiated back, some is bounced back to earth. Gives us climate sustainable for life. Heat is getting trapped causing global warming.

global warming vs climate change

global warming is the average increase in temperature, while climate change is seeing these affects in different areas

climate change being human-induced

Industrial Age

behaviors we can do to help reduce rate of climate change

dont drive as much, decrease carbon footprint, less electricity use, etc

explain why climate change is really not a debate

the increase has dramatically risen than previous years

misconceptions about climate change

"its getting warmer everywhere"

"its natural"

different types of biodiversity

genetic, chemical, ecosystem, species

ethical considerations of bioprospecting

why does biodiversity decrease towards the poles?

more energy being put into area, less livable area