Biology Test Chapter 10,11,12

Front 1

Bottleneck Effect:

Back 1

an event in which a population’s size is greatly reduced. When this happens, genetic drift may have a substantial effect on the population. In other words, when the population size is radically reduced, gene frequencies in the population are likely to change just by random chance and many genes may be lost from the population, reducing the population’s genetic variation.

Front 2

Genetic Drift:

Back 2

random changes in the gene frequencies of a population from generation to generation. This happens as a result of sampling error—some genotypes just happen to reproduce more than other genotypes, not because they are “better,” but just because they got lucky. This process causes gene frequencies in a population to drift around over time. Some genes may even “drift out” of a population (i.e., just by chance, some gene may reach a frequency of zero). In general, genetic drift has the effect of decreasing genetic variation within a population.

Front 3

Founder Effect

Back 3

changes in gene frequencies that usually accompany starting a new population from a small number of individuals. The newly founded population is likely to have quite different gene frequencies than the source population because of sampling error (i.e., genetic drift). The newly founded population is also likely to have a less genetic variation than the source population.

Front 4

Speciation:

Back 4

Changes in related organisms to the point where they are different enough to be considered separate species. This occurs when populations of one species are separated and adapt to their new environment or conditions (physiological, geographic, or behavioral).

Front 5

Allopatric speciation:

Back 5

Speciation that occurs when two or more populations of a species are geographically isolated from one another sufficiently that they do not interbreed.
gene flow: The movement of genes into or through a population by interbreeding or by migration and interbreeding.

Front 6

Non-random mating:

Back 6

individuals are more likely to mate with close relatives (e.g. their neighbors) than with distant relatives. This is common in the Amish community.
• Ellis Van Crevald Syndrome – Have symptoms of; Shortened Limbs, Malformed Heart and six fingers per hand

Front 7

Punctuated Equilibrium:

Back 7

hypothesis that suggests that much of evolutionary history is characterized by stasis punctuated by relatively rapid character change as a lineage splits. Available fossil evidence has highlighted several lineages that seem to follow this pattern of evolution.

Front 8

Gradualism Equilibrium:

Back 8

The Darwinian view of natural selection leading to slow, continuous evolution over long spans of time with occasional speciation is called gradualism.

Front 9

Convergent Evolution:

Back 9

: causes structures in different species to have similar form due to similar environmental pressures.

Front 10

Divergent Evolution

Back 10

causes structures in related species to have different form/function due to different environmental pressures

Front 11

Homologous Structures:

Back 11

The structures shared by a set of related species because they have been inherited, with or without modification, from their common ancestor. For example, the bones that support a bat's wing are similar to those of a human arm.
• Human Arms and Seal Flipper are homologous structures derived from a common ancestral structure.

Front 12

analogous structures

Back 12

Structures in different species that look alike or perform similar functions (e.g., the wings of butterflies and the wings of birds) that have evolved convergently but do not develop from similar groups of being born from the division of the zygote ((the earliest stage, in which joined egg and sperm have not yet divided), and that have not evolved from similar structures known to be shared by common ancestors. Contrast with homologous structures.

Front 13

Natural Selection:

Back 13

A process in which some individuals have genetically-based traits that improve survival or reproduction and and thus have more offspring surviving to reproductive age than other individuals. Because the offspring also carry the genes for these traits, this process causes the genes for advantageous traits to become more common in populations and the genes for disadvantageous traits to become less common in populations.

Front 14

stabilizing selection:

Back 14

A form of selection that tends to keep the form of a population constant. Individuals with the mean value for a character have high fitness (The success of an individual (or allele or genotype in a population in surviving and reproducing, measured by that individual's genetic contribution to the next generation and subsequent generations.; those with extreme values have low fitness).

Front 15

Directional Selection:

Back 15

favors one extreme phenotype

Front 16

disruptive selection:

Back 16

Selection favoring forms that deviate in either direction from the population average. Selection favors forms that are larger or smaller than average, but works against the average forms between the extremes.

Front 17

Balanced Polymorphism

Back 17

- A situation in which it is beneficial for a population to maintain two different alleles creating different phenotypes within the population. It’s also a change of shape. Examples such as Sickle Cell Anemia.

Front 18

Preadaptation:

Back 18

A characteristic evolved by an ancestral species or population that serves an adaptive though different function in a descendant species or population.

Front 19

adaptation:

Back 19

Any heritable characteristic of an organism that improves its ability to survive and reproduce in its environment. Also used to describe the process of genetic change within a population, as influenced by natural selection.

Front 20

Microevolution:

Back 20

evolution within a species or population. An increase in a particular gene’s frequency in a population due to natural selection is an example of microevolution.

Front 21

Macroevolution:

Back 21

can be defined simply as evolution above the species level, and its subject matter includes the origins and fates of major novelties such as tetrapod limbs and insect wings, the waxing and waning of multi-species lineages over long time-scales, and the impact of continental drift and other physical processes on the evolutionary process.

Front 22

adaptive radiation:

Back 22

The diversification, over evolutionary time, of a species or group of species into several different species or subspecies that are typically adapted to different ecological niches (The ecological role of a species; the set of resources it consumes and habitats it occupies.) (for example, Darwin's finches). The term can also be applied to larger groups of organisms, as in "the adaptive radiation of mammals."

Front 23

Quantitative Variation:

Back 23

Measured in degrees

Front 24

Discrete Variation:

Back 24

Control by 1 gene.

Front 25

Index fossils:

Back 25

(or zone fossils) are fossils used to define and identify geologic periods (or faunal stages). They work on the premise that, although different sediments may look different depending on the conditions under which they were laid down, they may include the remains of the same species of fossil. If the species concerned were short-lived (in geological terms, lasting a few hundred thousand years), then it is certain that the sediments in question were deposited within that narrow time period.

Front 26

Radioactive Dating:

Back 26

A method of determining the date at which an igneous rock solidified based upon the rate of decay of radioactive atoms within the rock.

Front 27

half-life:

Back 27

The amount of time it takes for one-half of the atoms of a radioactive material to decay to a stable form. For example, the half-life of carbon-14 is 5,730 years.A 19th-century scientist considered a father of modern geology. Lyell proposed that the geology of Earth is shaped by gradual processes, such as erosion and sedimentation. Lyell's ideas, expressed in his landmark work, Principles of Geology, greatly influenced the young Charles Darwin. Darwin and Lyell later became close friends. While Lyell initially opposed the idea of evolution, he came to accept it after Darwin published On the Origin of Species.

Front 28

Cuvier -

Back 28

At the beginning of the nineteenth century, the great French geologist and naturalist Baron Georges Cuvier proposed what came to be known as the Catastrophe theory or Catastrophism. Catastrophism is the theory that Earth has been affected by sudden, short-lived, violent events that were sometimes worldwide in scope.

Front 29

Lyell:

Back 29

Charles Lyell was the popularizer of uniformitarianism which is the idea that the earth is always changing in a slow pace.

Front 30

Lamarck, Jean:

Back 30

An 18th-century naturalist, zoologist, and botanist noted for his study and classification of invertebrates, as well as his evolutionary theories. He traveled extensively throughout Europe and was elected to the Academy of Sciences, where he introduced the principles of heredity and acquired characteristics which is the hereditary mechanism by which changes in physiology acquired over the life of an organism (such as muscle enlarged through use) are transmitted to offspring.

Front 31

Charles Darwin:

Back 31

He believed in evolution through natural selection

Front 32

acquired trait:

Back 32

A phenotypic characteristic, acquired during growth and development, that is not genetically based and therefore cannot be passed on to the next generation (for example, the large muscles of a weightlifter).

Front 33

vestigial:

Back 33

Any structures that have been greatly reduced in size and function over evolutionary time to the extent that they now appear to have little or no current function.
• Examples of vestigial structures in humans include wisdom teeth, the coccyx and the vermiform appendix.
• A whale’s pelvis is evidence of its evolution from four legged land-dwelling mammals.
• Eyes on a fish are not needed because they can’t see.

Front 34

Similarities of Developmental patterns:

Back 34

The human embryo and the chicken embryo have similar embryo’s each having a bony tail and simliar gill pouches which are simliar to those of a fish.

Front 35

Evidence for Evolution:

Back 35

In the 150 years since Darwin proposed the theory of evolution by natural selection, a mountain of evidence has accumulated to support the theory. A greatly expanded fossil record since Darwin's time, the discovery of DNA and the process of genetic replication, an understanding of radioactive decay, observations of natural selection in the wild and in laboratories, and evidence in the genomes of many different organisms, including humans, have all bolstered the validity of the theory of evolution.
• Peppered Moth
• Homologous Structures
• Fossil Record
• Vestigal Structures
• Preadaptation
• DNA
• Radioactive Dating

Front 36

Parts of the Theory of Evolution which are difficult to prove:

Back 36

The start of evolution

Front 37

What is the difference between gradualism and punctated equilbria

Back 37

1. Gradualism is the hypothesis that evolution occurs at a constant rate. Punctuated equilibria is the hypothesis that evolution occurs at an irregular rate.

Front 38

What did Stanley Miller and harold Urey demostrate

Back 38

2. They used an apparatus to simulate the conditions on the early Earth. The flask contains water and represents the ocean. Heating causes water to evaporate and move up a glass tube to the vessel representing the atmosphere. It contains a mixture of hydrogen gas, methane, ammonia, and water vapor. Sparks discharged into the mixture mimic the effects of lighting, stimulating reactions among the gases. Cold water circulates over the tubing, causing water vapor to condense, simulating rain. Thus, the products of any reaction in the “atmosphere” are carried back into the “ocean” where they can continue to react. Miller could remove samples for analysis through the valve.

Front 39

Arrange the following vertebrates in order of evolution, starting form the oldest to the most recent: bony fishes, amphibians, birds, mammals, dinosaurs, reptiles, jawless fishes, fish with jaws

Back 39

3. Jawless fishes, jawed fishes, bony fishes, amphibians, reptiles, dinosaurs, mammals, birds

Front 40

Give two examples of how natural selection has changed two species.

Back 40

At first giraffes were born with alleles for varying neck lengths. Some had short necks and some long. Giraffes with longer necks could reach for leaves in tall trees. They were getting better at getting food, but the short necks didn’t get enough food and the longer necks got more offspring. Since there were more longer neck offspring it became more common and short necks became rare.
With the increase of factories in England pale tree trunks were blackened by
heavy pollution from factories. Maybe moths sitting on soot darkened bark escaped being eaten by birds because it was hard for the birds to see the now dark moths against the dark background. Light colored moths however were easy to see and were eaten. When they reproduced dark moths produced dark moths. Vice versa.

Front 41

What are vestigial structures and what do they show.

Back 41

5. They show the remnants of an organism’s evolutionary past.

Front 42

Explain Darwin's discoveries with the Galapagos finches.

Back 42

6. In my book notes

Front 43

What is radioactive dating.Describe it's proccess

Back 43

7. In notes

Front 44

What are vestigial structures and homologous structures? Name an example of each.

Back 44

8. Already said in study guide

Front 45

Describe directional selection, stabilizing selection and disruptive selection

Back 45

9. Already in notes

Front 46

Evolution of ? began the production of oxygen.

Back 46

10. Cyanobacteria – photosynthetic eubacteria thought to be the first organisms to release oxygen.

Front 47

Be able to describe the concept of natural selection

Back 47

11. In notes

Front 48

Name one method of dating fossils

Back 48

12. Already in notes

Front 49

What are fossils

Back 49

13. Tracks of dinosaurs, footprints of human ancestors, insects trapped in sticky tree sap, impressions of leaves or skin and animals buried in tar are all fossils. For fossils to form very special conditions are needed. The dead animal must be buried in sediment. (Solid fragments of inorganic or organic material that come from the weathering of rock and are carried and buried by wind, water, or ice) Burial is in ocean floor, in swamps, in mud, or in tar pits. Calcium in the bone or in the shell is slowly replaced by other, harder minerals. Usually skin or muscle is not fossilized.

Front 50

Why is the ozone layer improtant to the survival of life on land?

Back 50

14. Ozone which is a gas that has the remarkable and very fortunate property of absorbing ultraviolet radiation. In the upper atmosphere, ozone acted like a great shield blocking out ultraviolet radiation. This made the Earth’s surface a safe place to live.

Front 51

Why are transitional species crucial evidence of evolution

Back 51

15. Because then they show how new species evolved from existing species, which was one of Darwin’s main arguments.

Front 52

Describe the steps the scientists used to determine whether organic molecules that make up living things could form under conditions found on early Earth.

Back 52

16. Methods- Mix molecules found in early atmosphere. Stimulate reactions with heat and electricity. Collect and analyze products of reactions.
Key Assumptions – Experiment matches conditions on early Earth, in temperature and chemical composition. Experiment has not been contaminated by bacteria which could also produce organic molecules.
Results - Complex mixture of organic molecules forms; contains amino acids.
Conclusions – Organic molecules could have formed on early Earth before life existed. Experiments steps in question 2.

Front 53

If you start with a population of 10 fast zebras and 90 slow zebras how will fast zebras become more abundant.

Back 53

17. Over a period of time the slow zebras will die off. Look at question 4.

Front 54

How do environmental conditions lead to ecologicial races, divergence, and eventually a new species

Back 54

18. Ecological races - are populations of the same species that differ genetically because they have adapted to different living conditions.
Divergence - The accumulation of differences between species or populations. Eventually races can accumulate so many diffrences that biologists consider them separate species. Examples are the Dusky seaside sparrow, Gulf seaside sparrow, Cape Sable seaside sparrow and seaside sparrow.

Front 55

Sickle Cell Anemia

Back 55

Look in textbook pg 183

Front 56

Heterotroph Theory

Back 56

In Favorites on the internet

Front 57

Other evidence for evolution besides fossils

Back 57

In notes.