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Biology Test Three Flashcards

0
Q

Population

A

Group of organisms of the same species living together in the same geographic area.

Formed by a new allele making genetic changes in a species, thus making or changing a species to have an advantage.

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1
Q

Natural selection/ Adaptive evolution

A

Darwin

Environment selects favorable traits to have species be more adaptive and have higher reproduction rate.

Differential survival and reproduction of individuals in response to environmental pressure that leads to change in allele frequencies In a population over time.

Leads to adaptation
Acts on the phenotypes of organisms

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2
Q

Descent of modification

A

Darwin’s idea of natural selection was original contribution to this theory.

Combines the ideas that all living things are related sharing common ancestors in distant past and that organisms have changed over time.

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3
Q

Evolution

A

Change in allele frequencies in a population over time.

It’s the gradual change of species over time.

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4
Q

Nonadaptive evolution

A

Any change in allele frequency that does not by itself lead a population to become more adaptive to its environment

Caused by mutations.

Caused by genetic drift

Caused by gene flow

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5
Q

Mutations

A

Cause of Nonadaptive evolution

Introduces new alleles into a population.

Change in a gene frequency

Results in evolution.

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6
Q

Genetic drift

A

Cause of Nonadaptive evolution

Change in allele frequencies between generations that occurs purely by chance.

Completely random

Decreases the genetic diversity of a population

Two types: founder effect, bottleneck effect

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7
Q

Founder effect

A

Type of genetic drift

Small number of individuals or founders leave one population and establish a new population .
May have lower genetic diversity than original population.

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8
Q

Bottle neck effect

A

Type of genetic drift

Occurs when a population is suddenly reduced to a small number of individuals and alleles are lost from the population As a result

Less genetic diversity or extremely poor gene pool.

Can occur from natural causes

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9
Q

Gene flow

A

Cause of Nonadaptive evolution

Movement of alleles from one population to another

May increase genetic diversity of a population

Aka migration

Ex. Pollen being blown to a new destination.

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10
Q

Fit

A

Organisms fitness

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11
Q

Fitness

A

Relative ability of an organism to survive and reproduce in a particular environment.

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12
Q

Gene pool

A

Each population of any organism has its own particular collection of alleles.

Total collection of allele in a population.

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13
Q

Allele frequency

A

Within the gene pool

Relative proportion of an allele in a population.

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14
Q

Genetic diversity importance

A

Diverse gene pool gives a pop. More flexibility to survive in a changing environment

Improve evolutionary success.

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15
Q

Tiktaalik roseae

A

Between 4-9 ft long

Had fins, scales, a mobile neck, jointed wrist, finger like bones, flat skull, flexible neck, long sturdy ribs.

It was a predatory fish with sharp teeth.

Intermediate or transitional fossil between figs and tretrapods

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16
Q

Fossils

A

Preserved remains or impressions of a once living organism that provides a record of past life on earth.

Direct evidence of evolution.

17
Q

Ways fossils are formed

A

Frozen, trapped, buried, leave imprint

18
Q

Two kinds of fossil dating

A

Relative-determine age of fossil from its position relative to layer of rock or fossils of known age.
Deeper down they are buried, the older they are.

Radiometric- the rock layers formed from volcanic eruptions. Can be directly dated using Radiometric dating.
Used as a geological clock.
Ratio of radioactive elements of uranium and lead in the rock determine the age.

19
Q

Fossil record

A

Group of fossils arranged in order of age providing evidence of changes in species over time.

20
Q

Homology

And the three forms

A

Anatomical genetic DNA,or developmental similarity among organisms due to common ancestry.

3 forms:
Anatomical- number, order, and structure of the forelimb bones.
Embryological- similar e structures in vertebrates are evidence that all vertebrates share common ancestor.
DNA- closely related species have similar DNA inherited from ancestors.

21
Q

Biological species concept

A

Defines a species as a population whose members can interbreed and produce fertile offspring.

22
Q

Taxonomy

A

The process by which scientists systematically identify the name and classify organisms on the basis of a shared trait.

23
Q

Taxonomists

A

Scientists who identify, name, and classify organisms.

24
Q

Scientific name

A

Written in italics

Genus is first and uppercase

Species is second and lower case

25
Q

Classification of species

A 
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
26
Q

Modern system of classification

A

Bacteria
Archaea
Eukarya- encompasses multicellular and unicellular organisms that are grouped together by their similar DNA sequences

Kingdom- Plants, animals, fungi, Protists within eukarya domain.

27
Q

Reproductively isolated species

A

Members of different species cannot breed with each other

Occurs as a result of mechanisms that prevent mating including the gene flow between members of different species.

28
Q

Factors that cause isolated species

A

Ecological- two species live in dif environments become isolated and never encounter one another
Temporal- mating fertility or behavior at dif times
Mechanical- mating organs are incompatible
Gametic-gametes of two species cannot unite.

29
Q

Speciation

A

Genetic divergence of population of the same species when a barrier prevents gene flow between them, leading over time to reproductive isolation and the formation of new species.

Barrier can be river, mountain, hill, ocean.

30
Q

Extinction

A

Elimination of all individuals in a species

May occur over time or a sudden mass die off

31
Q

Two massive extinctions

A

Permian- occurred 290mil years ago. 95% of species died off.

Cretaceous- occurred 65mil years ago. 60% of other species and dinosaurs died off.

32
Q

Three domains of life

A

Bacteria, archaea, and eukarya.

Three fundamental branch points in the trunk of the evolutionary tree.

33
Q

Prokaryotes

A

Unicellular organisms that lack internal membrane bound organelles.
No nucleus
Single circular DNA molecule floats freely in cytoplasm.

Bacteria and archaea

34
Q

Bacteria

A

Domain of prokaryotes

Some are
autotrophs- self feeders and harmless and beneficial. Ex. Cyanobacteria.
Heterotrophic- obtain food by consuming materials. Important de composers.
Disease causing pathogens by producing toxins. Staff bacteria is bad.

35
Q

Domains of archaea

A

Domain of prokaryotic life.

Known as extremophiles since they live in harsh environments.
Many are anaerobic- no oxygen and rely on sulfur in their metabolism. Ex. Methanogens.

36
Q

Eukaryotes

A

In the eukarya domain.
Have membrane enclosed nucleus and organelles.
Contains plants, fungi, animal, and Protists

37
Q

Plant diversity

A

Multicellular eukaryotes that carry out photosynthesis. Has cell wall and is adapted to living on land.
Land plants evolved first from water dwelling algae.
Vascular plant- plant with tissue that transports water and nutrients thorough plant body.

Evolution:
bryophytes-made transition from water to land. Non vascular and don’t produce seeds. Moss
Fern-first true vascular plant. No seeds. Can stand upright reproduces by spores.
Gymnosperm-vascular. Cell walls provide support. Grows tall. Naked seeds. Pine
Angiosperm- flowering plants. Vascular. Have seeds contained in fruit. Rose, Lilly, maple

38
Q

Animal diversity

A

Multicellular eukaryotic organism. Heterotrophs. Body is symmetrical.

Vertebrae: bony backbone CHORDATES.

Invertebrate: animal lacking backbone.
Insects and Arthropods.

39
Q

Fungi

A

Unicellular or multicellular eukaryotic organism.
Obtains nutrients by secreting digestive enzymes onto organic matter or dead organisms and absorbing digested product.
Decomposers- digest and use organic molecules in dead organisms as fuel.

40
Q

Protist

A

Eukaryotes. Cannot be classified as plant, animal, or fungus.

Usually unicellular.

Include photosynthetic plantlike algae and animal like protozoans.

Lack adaptations to live on land such as roots stems and leaves.

41
Q

Mitochondrial DNA

A

DNA in the mitochondria. Solely inherited from mothers.

Located in the mitochondria of our cells.
Powerful tool by which to track human ancestry back hundreds of Generations.
Used to construct an evolutionary tree of humanity.

There is a mitochondrial eve that we all can trace back to.

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