Biology Ch. 9

Front 1

First filial (F1) generation

Back 1

-the first generation of offspring
-when Mendel crossed 2 purple flowers with 2 white flowers

Front 2

Allele

Back 2

-each gene contributes an allele to the genotype

Front 3

Law of Segregation

Back 3

-states that alleles segregate independently of each other when forming gametes
-phenotypic expression of the alleles is not a blend of the two, but an expression of the dominant allele

Front 4

Law of Independent assortment

Back 4

-states that genes located on different chromosomes assort independently of each other

Front 5

Karyotype

Back 5

-a map of chromosomes

Front 6

Barr Body

Back 6

-In most somatic cells, one of the X chromosomes will condense, and most of its genes will become inactive.
-Formed at random, so the active allele is split evenly in most somatic cells
-in most cases, the recessive phenotype is only displayed in homozygous recessive individuals.

Front 7

Dihybrid cross

Back 7

-A cross between two parents that are heterozygous for two separate traits.
-results in a 9:3:3:1 ratio
-the two parents are genetically identical at the genes compared.

Front 8

Dihybrid

Back 8

-Offspring that is heterozygous for both traits considered.
(AaBb).

Front 9

Evolution

Back 9

-the change in a gene pool.

Front 10

Gene pool

Back 10

-the total of all alleles in a population population

Front 11

Vertebrata

Back 11

-a subphylum within the phylum chordata

Front 12

Mammalia

Back 12

-a class containing all mammals, within the phylum chordata.

Front 13

Species

Back 13

-loosely limited to, but not inclusive o, all organisms that can reproduce fertile offspring with each other.
-all organisms that normally reproduce selectively fit offspring in the wild.

Front 14

Survival of the fittest

Back 14

-predicts that one species will exploit the environment more efficiently, eventually leading to extinction of the other with the same niche.

Front 15

the "fittest" organism

Back 15

-organism that can best survive to reproduce offspring which will, in turn reproduce offspring and so on generation after generation.

Front 16

r-selection strategists

Back 16

-produce large numbers of offspring that mature rapidly with little or no parental care
-generally found in unpredictable rapidly changing environments
-growth curve is exponential.

Front 17

k-selection strategists

Back 17

-organisms that have small brood size with slow maturing offspring and strong parental care.
-tend to have a sigmoidal growth curve which levels off at the carrying capacity

Front 18

Carrying capacity

Back 18

-the maximum number of organisms that an environment can maintain

Front 19

Speciation

Back 19

-the process by which new species are formed.
-occurs when gene flow ceases between two sections of a population.

Front 20

Adaptive radiation

Back 20

-occurs when several separate species arise from a single ancestral species.

Front 21

Evolutionary bottleneck

Back 21

-when a species faces a crisis so severe as to cause a shift in allelic frequencies of the survivors of the crisis.

Front 22

Divergent evolution

Back 22

-exists when two or more species evolving from the same group maintain a similar structure from the common ancestor. (homologous structure)

Front 23

Convergent evolution

Back 23

-two species may independently evolve similar structures (analogous structure)

Front 24

Polymorphism

Back 24

-the occurrence of distinct genetic forms

Front 25

Hardy-Weinburg Equilibrium

Back 25

-statistically shows that there should be no change in the gen pool of a sexually reproducing population possessing the five following conditions:

1. large population
2. mutational equilibrium
3. immigration or emigration must not change the gene pool
4. random mating
5. no selection for the fittest organism

-no real population ever possesses all of these characteristics completely
-last two conditions are the most influential mechanisms of evolution

Front 26

Genetic drift

Back 26

-small populations-one allele may be permanently lost due to death of all members having the allele.
-not caused by selective pressure-random

Front 27

Mutational equilibrium

Back 27

-the rate of forward mutations equals the rate of back mutations

Front 28

The binomial theorem

Back 28

-predicts the genotype frequency of a gene with only two alleles in a population in Hardy-Weinberg equilibrium.

p^2 + 2pq + q^2

take the percentage of alleles and plug into this equation to find the probability that the two alleles will join together, finds the percentage of the new population with the homozygous and heterozygous members.
since there are only two alleles, P + q = 1.

Front 29

Urey-Miller Experiment

Back 29

-Experiment attempting to recreate the atmosphere of early earth that resulted in the autosynthesis of molecules such as urea, amino acids, and adenine.

Front 30

Coacervates

Back 30

-lipid or protein bilayer bubbles
-spontaneously form and grow from fat molecules suspended in water.

Front 31

Age of the oldest fossils

Back 31

3.6 bya

Front 32

Deuterostomes

Back 32

-anus develops from or near the blastopore, mouth developes on opposite end
-chordates are deuterostomes

Front 33

Chordate features

Back 33

-phylum containing human beings
-deuterostomes
-have a coelom
-possess a notochord, pharyngeal slits, a dorsal, hollow nerve chord, and a tail.

Front 34

Vertebrata

Back 34

-notochord is replaced by segmented cartilage or bone structure
-distinct brain enclosed in skull
-most chordates are vertebrates