Unit 1 COLLEGE biology (introductory) (copy)

for ivy tech heheh

gene expression

The process of turning on a gene to produce RNA and protein, leads to speciation

why gene expression is necessary

if there is no gene expression, will make every gene (protein) all the time, using lots of resources + space

transcription (DNA to RNA)

where most gene regulation occurs in prokaryotes

simultaneously

when does transcription and translation happen in prokaryotic cells

repressors

 proteins that suppress transcription of a gene in response to an external stimulus

activators

proteins that increase the transcription of a gene in response to an external stimulus, multiple of these= enhancers

inducers

small molecules that either activate or repress transcription depending on the needs of the cell and the availability of substrate

operons

Proteins that are needed for a specific function are encoded together in blocks

Jacob and Monod

 the first to show the organization of bacterial genes into operons through the lac operon

transcription factors

 proteins encoded by regulatory genes

RNA polymerase

makes mRNA strand

operator

regulatory region located between the RNA polymerase binding site of the promoter and the transcriptional start site of the first structural gene

sequence of an operon

promoter, operator, structural genes (in that order)

the 3 regulators

activator, repressor, inducer

constitutively expressed

Gene products that are needed consistently are ________ in prokaryotes.

enhancers

regions that help increase or enhance the transcription of a distant gene, made up of activators

splicing

when original DNA or RNA sequence is split up to only leave what needs to be turned into a protein

exons

The regions of DNA or RNA that code for protein

introns

a segment that doesn’t code for a protein + interrupts sequence

miRNA (microRNA)

short single-stranded RNA molecules that are only 21–24 nucleotides in length.  Like transcription factors and RBPs, mature miRNAs recognize a specific sequence and bind to the RNA to degrade the target mRNA.  They rapidly destroy the RNA molecule.

poly-A tail

long chain of adenine nucleotides added to mRNA to increase stability

5’ cap

placed on 5’ end of mRNA to keep it from degrading when attached to poly-A tail (mRNA)

3’ cap

placed on 3’ end of poly-A tail to keep from degrading when attached to mRNA (POLY-A TAIL)

5’ end

phosphate

3’ end

sugar

RNA stability

the rate an RNA molecule decays at, it’s lifespan

nuclear pore complex

holes in the nucleus that mRNA can come out of

RNA splicing, RNA shuttling, RNA stability

the 3 versions of post-transcriptional control, if only one of these is not completed a protein can’t be synthesized

histones

the proteins DNA wraps around to make chromatin

nucleosome

DNA wrapped around a histone to control what parts of DNA can be accessed by proteins.

epigenetic regulation

regulation due to histones making DNA accessible or inaccessible in eukaryotes

sympatric speciation

when speciation happens even though they are not geographically seperated

allopatric speciation

speciation caused by a geographical barrier

promoter

where RNA polymerase and the transcription factors bind

DNA bending protein

 brings an enhancer into contact with transcription factors so it can increase transcription

pea plant

Pisum Sativum, what Mendel used

trait

a variation in the physical appearance of a heritable characteristic

law of segregation

each gamete only gets one copy of a gene

blending theory of inheritance

What Lamarck believed (the giraffe guy)

continuous variation

like polygenic traits, have a continuous number of phenotypes

discontinuous variation

monohybrid traits, dihybrid traits, non-polygenic traits; limited number of phenotypes

model system

models that represent biological circumstances to run experiments on

incomplete dominance

traits mix, neither is completely expressed

codominance

spots, both traits are present

autosomes

non-sex chromosomes

hemizygous

when you only have 1 copy of a chromosome (males are hemizygous for x chromosomes)

wild type

the most common geno/phenotype found in the wild, usually abbreviated with a +

variants

any other geno/phenotype that is not most commonly found in the wild (like albinism)

pleiotropic gene

a gene that affects multiple characteristics. inherited like single trait alleles

multifactorial characteristics

Characteristics that are influenced by environmental as well as genes

H.M.S Beagle

the ship Darwin traveled the world on

convergent evolution

what makes vestigial structures, two organisms with similar traits but evolved seperately

human economic pressures

One of the foundational concepts of natural selection was an essay on ________.

divergent evolution

2 species that evolved similar traits due to a common ancestor

evidence for evolution

fossil record, embryology, comparative anatomy, biogeography, molecular biology

microevolution

change of alleles over generations

macroevolution

creation of new species

population genetics

The field of biology that studies allele frequencies in populations and how they change over time

adaptive evolution

increasing the frequency of beneficial traits

frequency-dependent selection

there are 3 different lizards. Like a game of rock-paper-scissors, orange beats blue, blue beats yellow, and yellow beats orange in the competition for females. THE FREQUENCY OF ONE TRAIT IS DEPENDENT ON ANOTHER.

sexual dimorphisms

differences between males and females of a species

handicap principle

some sexual adaptations can put members of species at risk. (like a bright tail) this is the idea that the more risk, the more fit an individual is, since they can handle that risk

good genes hypothesis

the idea that males have ornamental sexual traits because it corresponds with better genes

honest signal

the idea that ornamental sexual traits on males mean they are actually superior and are not a “trick”

perfect organism

natural selection will never create a ______.

bottleneck effect

type of genetic drift where lots of alleles are taken out by a catastrophic event

founder effect

type of genetic drift where a small group separates and creates own population with their set of alleles

gene flow

flow of alleles in and out of a population due to migration

phylogeny

the evolutionary history and relationship of an organism or group of organisms

phylogenetic tree

taxonomy

domain, kingdom, phylum, class, order, family, genus, species

binomial nomenclature

the two-word scientific name of a species. ex: *Canis lupus*

taxon

the names of each level of taxonomy (domain, kingdom, etc)

unrooted phylogenetic tree

shows relationships but not time

rooted phylogenetic tree

shows relationships and time

carriers

2 parents can never both be _____.

biosphere

collection of all ecosystems

order of the biosphere

organism, populations, communites, ecosystems, biosphere (OPCEB)

Order (Property of Life)

made of cells

Regulation (Property of Life)

the way body temp, blood pressure, energy usage, etc. is regulated

Homeostasis (Property of Life)

variables in body have to be at a “set point”

Order, Stimuli, Reproduction, Growth, Regulation, Homeostasis, Energy processing (OSRGRHE)

The properties of life

community

a group of organisms interacting together

ecosystem

a community and the abiotic (nonliving) factors that impact them

population

a group of organisms of the same species

alpha diversity

diversity within a particular area, community or ecosystem, compare total # of taxa in each area

beta diversity

diversity between ecosystems; compare # of taxa unique to each area

gamma diversity

a measurement of the overall diversity for different ecosystems within a region

capitalized genus + lowercase species

format of binomial nomenclature

animal

heterotroph (eats for energy), eukaryotic + mulitcellular, most are able to move + produce sexually

exctant

died off, extinct

body plan

a group of structural characteristics used to identify a taxon

parazoa

a taxonomic subkingdom within the kingdom Animalia; the sponges

Eumetazoa

a taxonomic subkingdom, within kingdom Animalia; all animals except the sponges

epithelial tissue

one of the four basic types of animal tissue, which line the cavities and surfaces of structures throughout the body, and also form many glands

metamorphasis

a change in the form and often habits of an animal after the embryonic stage during normal development

hox gene

genes responsible for determining the general body plan, such as the number of body segments of an animal

blastula

a 6-32-celled hollow structure that is formed after a zygote undergoes cell division

radial symmetry (body plan)

bilateral symmetry (body plan)