Biology B
How old is the earth?
4.6 billion years old
What is a gene pool?
A combined genetic information of all the members of a particular population.
Selective Pressure
A force that would cause natural selection.
What is Divergent Evolution? (Adaptive Radiation)
A single species evolves into many species. This often occurs after a mass extinction.
Population
All of the same species that live in the same geographic area. They will most likely mate within their population
Heterozygous
An organism that has two different alleles for a particular trait.
Homozygous
An organism that has two identical alleles for a particular trait.
Why is Biochemical comparisons different from the other methods of comparing animals?
Biochemical comparisons looks at the genotype and other types look solely at the phenotype.
What is the Molecular Evidence for Evolution?
By comparing amino acid differences in proteins of two species, relationship is determined. The differences are proportional to the length of time that has passed since the two species shared a common ancestor.
What is Behavorial Isolation?
Can interbreed but have different mating rituals.
Gamete
Cell involved in sexual reproduction
What is Convergent Evolution?
Distantly related organisms come to resemble one another. Two species have the same characteristic but if their common ancestor didn't have that characteristic then it's Convergent Evolution. Insects and Birds-Analogous structures for flight.
Homologous Chromosomes
Each chromosome from the mother has a corresponding chromosome from the dad. Contains the same type of info.
What is Embryology?
Early stages of different embryos are very similar and develop in the same order, indicating that they share a common ancestor in the past.
What is Endosymbiotic Theory?
Eukaryotic Cells formed from a symbiosis among several different Prokaryotic Cells.
Zygote
Fertilized egg by sperm
What does Meiosis create?
Gametes-sex cells
Genotype
Genetic makeup of an organism
What type of cells are Gametes?
Haploid-half
What are the three types of genetic variation that can occur in Meiosis?
Mutations, Independent Assortment, and Crossing Over
What are the four sources of genetic variation?
Mutations, Random Fertilization, Independent Assortment, and Crossing Over
What are two pieces to support Endosymbiotic Theory?
One Prok. cell has the ability to use oxygen to make ATP. Other pork. cells evolves in chloroplasts of plants and algae because of photosynthesis.
Allele
One of a number of different forms of a gene.
What was Lamark's theory of evolution?
Organisms acquire or lose traits in their lifetime, those traits are passed on to their offspring, and this process led to change in a species (evolution)
Phenotype
Physical characteristics of an organism
What is the order of the eras?
PreCambrian, Paleozoic, Mesozoic, and Cenozoic.
What are the first three organisms on earth?
Prokaryotic Cells, Eukaryotic Cells, and Multicellular organisms
What are Homologous Structures?
Similar feature that were inherited from a shared ancestor. These features have a similar structures but different functions.
What is Disruptive Selection?
Single curve splits into 2. It occurs individually at the upper and lower ends which have higher fitness levels. The middle has a lower fitness level.
What is Geographic Distribution of Living Things?
Some species have similar adaptations but aren't recently related.
What is speciation?
Speciation means that a formation of a new species.
What is Coevolution?
Species that interact can coevolve. Toxic Newt and the snake.
What are Vestigial Structures?
Structures that were functional to an ancestor but no functional to the modern organism. Won't be eliminated by natural selection that doesn't harm and organisms's ability to live long enough to reproduce.
What is Stabilizing Selection?
The center has higher fitness than individuals at either end.
Evolution
The change of the genetic makeup of a population over a period of time.
Two species have similar amino acid sequences, is their DNA similar too?
The greater the similarities in the amino acid sequence the closer they are related to evolution. But after a lot of time the two species have had time to have differences in the amino acid chain.
Why are amino acid sequences compared to a molecular clock?
The greater the time the more differences. The greater the similarities the shorter the time can be expected has passed.
What is Binomial Nomenclature?
The species name. Consists of two words written in italics, the first word is the genus, and the second word consists of the specific epithet and its lower case.
What is Darwin's theory of evolution?
There is genetic diversity within each species, some organisms have advantageous adaptations for their environment, those with advantageous adaptions live longer and reproduce, and their genes and alleles are removed from the population.
How many divisions are in Meiosis?
Two divisions
What is Geographic Isolation?
Two populations are separated by a geographic barrier.
What is Temporal Isolation?
Two species reproduce at different times.
What is Directional Selection?
When individual at one end of a distribution curve have higher fitness than individuals in the middle or at the other end.
What is reproductive Isolation?
When two populations cannot interbreed.
What are Fossil Records?
You can observe a change in species over time through the layers in the earth.
What type of RNA brings the code from the nucleus to code for other amino acids?
mRNA