Q201 Final Exam

How is the base sequence of a DNA molecule transcribed into the base sequence of a mRNA molecule?

sense strand

gel electrophoresis

seperates DNA fragments on their bases of electrical charge and size

overexploitation

species diversity declining due to over-use (elephants killed for tusks)

epidemic species

species that are unique to a specific geographic area (an island, nation, zone, etc.)

promoters

specific signals found in the base sequence of the DNA molecule that TELL THE RNA POLYMERASE WHICH STRAND OF DNA MOLECULE IS SUPPOSED TO BE TRANSCRIBED

DNA Fingerprinting

-STRs used to produce these Uses: Forensics/criminal cases, Paternity cases, Immigration cases, Endangered species/wildlife poaching, Purebred/thoroughbred animals

RNA polymerases role

enzymes that synthesize RNA

We find evidence of the first stone tools associated with which hominin species? What do we call the types of tools that they made?

-Homo heidelbergensis/Archaic Homo sapiens (AHS) -Acheulian tradition

transfer RNA

-acts as an adapter between the mRNA and the growing protein chain. -recognizes nucleotides triplets in the mRNA molecule and carries the correct amino acid to the ribosome

ribosomal RNA

-composed of ribosomal RNA plus proteins- consists of a large and small subunit. -PROTEIN SYNTHESIS occurs here, AMINO ACIDS JOINED TOGETHER TO MAKE PROTEIN

key characteristics of Homo habilis

-larger brain -stone tools -smaller teeth

Lamarck's thinking

-shown to be incorrect -believed in transformism, species change over time into new species -ex: giraffes necks are long because they stretched them hard to reach leaves and passed stretched necks onto their offspring

transcription

-synthesis of RNA from a DNA template *RNA molecules are complementary to the DNA* (Ex: A DNA = U RNA)

3 types of natural selection

1. stabilizing selection, an intermediate population is favored 2. directional selection, individuals at one end of the phenotypic range survive and reproduce more successfully 3. diversifying selection, individuals on both extremes of a phenotype are favored over intermediate phenotypes

Evidence for evolution

1.) Fossils 2.) Biogeography 3.) Comparative Anatomy 4.) Comparative Embryology 5.) Molecular Biology

what percent of energy goes to the next trophic level?

10%

what is the age of homo sapiens sapiens

195,000 years

hominins

7,000,000 years ago, found in Africa

To which genus did the earliest, well-known hominins belong?

Australopithecines

Evolution of the species Homo is associated with the development of which features?

Brain?

Casts

Dead organisms trapped in sediment decay & leave behind an empty "mold" that fills with minerals dissolved in water (ex: marine shells)

Semi Conservative DNA replication

Each strand of the old DNA molecule acts as a template (pattern) for the synthesis of a new, complementary DNA strand

Preserved organisms

Entire organisms/parts of organisms, including soft parts, may be buried in a medium that prevents bacteria and fungi from decomposing the organism (ex: fossilized leaves/insects in amber)

Evolution

Genetic change in a population or species across/between generations

Homo habilis, archaic Homo sapiens(Homo heidelbergensis), and modernHomo sapiens skull differences

Habilis: 630 cc 50% size of modern humans, skull is lower in the back compared to modern humans Archaic/heidelbergensis: 1200cc 90% size of modern humans, higher rounded skulls

Artificial Selection

Humans provide the selective pressure by choosing the individuals that will breed

Inherited vs acquired characteristics

Inherited: a characteristic that can be handed down genetically Acquired: a characteristic that has been produced based on personal efforts to make the change

intrasexual selection vs intersexual selection

Intra: physical combat or displays between members of the same sex as they compete for a mate Inter: individuals of one sex select their mate based upon certain characteristics

Leading strand vs. lagging strand (differences in the way in which each is replicated)

Leading: synthesized continuously in a 5' to 3' direction Lagging: synthesized as a series of fragments called Okazaki fragments, which are later joined together by DNA ligase

Two Perspectives of Evolution

Macroevolution: Change in the FORM/BEHAVIOR of organisms between generations Microevolution: Change in the GENE FREQUENCIES between generations

Petrified Organisms

Minerals dissolved in ground water seep into tissues of dead organisms, and replace organic matter

What types of tools did the Neandertals make?

Mousterian ex: spears

elongation

RNA grows LONGER. New RNA molecule peels away from DNA and DNA double helix closes up again

initiation

RNA polymerase ATTACHES TO PROMOTER and begins to SYNTHESIZE RNA, using ONE STRAND of the DNA molecule as a template

termination

RNA polymerase reaches a terminator sequence in the DNA molecule and stops making RNA. New molecule is released

differences between the Robust and Gracile australopithecines

Robust: larger temporal, shorter snout, flatter forehead, smaller front teeth, larger molars Gracile: smaller temporal, longer snout, steeper forehead, larger front teeth, smaller molars These two species split because of the dropping temperatures in Africa

Diet of the Robust australopithecines vs. Homo habilis vs. Homo erectus vs. Neandertals, and how each obtained their food.

Robust: nuts, seeds, hard fruits, scavengers Habililis: meat scavengers Erectus: scavengers but probably more hunting Neanderthals: hunter, meat

Comparative embryology

The development of different organisms, closely related organisms have similar development patterns

Molecular Biology

Universal genetic code

restriction enzyme

enzymes that recognize specific base sequences in a DNA molecule and cut the DNA molecule at a specific site within that base sequence

ecosystem

a biotic community interacting with abiotic factors in the environment

sexual selection

a form of natural selection where individuals with certain traits are more likely than other individuals to find mates

codon

a group of three adjacent nucleotides in a mRNA molecule that specifies a particular amino acid in a protein, or specifies a start or stop signal

symbiosis

a physically close association between organisms of two or more species

plasmid

a small circular DNA molecule that is SEPARATE from the chromosome of a BACTERIAL CELL, into which a piece of foreign DNA can be inserted can be inserted and undergo replication

PCR (polymerase chain reaction)

a technique used produce millions of copies of a specific section of a DNA molecule uses: amplify DNA from crime scenes, paternity cases, immigration cases

gene flow

allele frequencies in a population can change when a population gains or loses alleles when fertile individuals move into or out of a population

selection

any pressure that causes one individual to die or not reproduce, while others having a different set of characteristics do survive and reproduce

bioaccumulation vs biomagnification

bioaccumulation: accumulation of toxins in an INDIVIDUAL organism biomagnification: accumulation of toxins in the food chain

messenger RNA

carries the genetic information FROM THE DNA in the nucleus TO THE RIBSOMES

genetic drift

chance events cause allele frequencies to fluctuate unpredictably from one generation to the next

Zygomatic arch

cheekbones

Comparative Anatomy

comparison of body structures in different species (ex: wing of bird)

requirements of natural selection

competition among individuals, heritable variation, selective pressures

FOSSIL evidence for evolution

complexity increasing through time or appearing/disappearing body parts

DNA double helix

double stranded line of sugar-phosphate backbone , A PAIRS WITH T, G PAIRS WITH C. Two strands are antiparallel

trophic structure

feeding relationships between organisms

value of biodiversity

foods, genes, biological control agents, natural products

diastema

gap between two teeth (with early hominins, was the space between canine teeth and front teeth)

bottleneck effect

genetic drift resulting from a drastic reduction in population size

founder effect

genetic drift that occurs when a few individuals become isolated from a larger population and form a new population whose gene pool is not reflective of the original population

mutations

heritable change in the nucleotide sequence of a DNA molecule

Which hominin species was the first to leave Africa?

homo erectus

what type of bond holds together strands of DNA?

hydrogen

3 Different Types of Fossils

impression, petrification, preservation

sagittal crest

ridge of bone running down the center of the top of the skull, used to anchor chewing muscles

where are toxins stored?

in fat (milk has a high fat content!!!)

BIOGEOGRAPHICAL evidence for evolution

individuals will resemble their relatives more than non-relatives in similar but distant places (example: ensantina salamander)

gene

linear sequence of NUCLEOTIDES in a DNA molecule that SPECIFIES THE LINEAR SEQUENCE OF AMINO ACIDS IN A PROTEIN

biomes

major ecosystem types occuring over a broad geographic area (Tropical Rain Forest, Temperate Deciduous Forest, Chaparral, Temperate grasslands, Deserts, Arctic Tundra, Coral Reefs, Hydrothermal Vents (deep sea vents), Rivers, Streams, Lakes, Wetlands)

sexual dimorphism

males and females have different appearance or size

what do we need to make a protein?

messenger RNA (mRNA), ribosomal RNA (rRNA), transfer RNA (tRNA)

Interactions

mutualism: both organisms benefit predation/grazing/parasitism: one organism benefits, one is harmed commensalism: one organism benefits, the other is not hurt nor benefits competition: both organisms are harmed

invasive exotic species

non-native species introduced intentionally or unintentionally

introns

non-protein coding sequences

monomer

nucleotides that consist of three parts: nitrogen base, 5 carbon sugar, and a phosphate group

Darwin's theory of natural selection

occurs when individuals that are better suited to survive and reproduce do so, leaving more offspring than their competitors in the next generation. (ex: The birds prefer the taste of the red bugs, so soon there are many green bugs and few red bugs. The green bugs reproduce and make more green bugs and eventually there are no more red bugs)

what type of bond forms between amino acids in DNA synthesis?

peptide bond

nucleotides are joined together by _________ bonds

phosphodiester

services provided by living organisms

pollinate plants, producing O2, filter water

community

populations of 2 or more organisms, living and interacting in an area

evolutionary theory

predicts life originated once, began with a simple single celled organism

DNA cloning

producing large numbers of identical DNA molecules- not possible until 1970s

exons

protein coding sequences

two types of biomes found on earth

terrestrial and aquatic

foramen magnum

the hole in the base of the skull through which the spinal cord passes

gene pool

the set of alleles present in a population

ecology

the study of biotic and abiotic interactions in the environment

translation

the synthesis of a polypeptide using the genetic information encoded in an mRNA molecule

bipedal

walks on two legs- hominid trait proof of it: Pelvic bones, leg structure (knee turned outward), laetoli footprints

Scientific Definition of Theory

well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment