Flashcards in Final Exam Deck (73)
What is evolution?
a change in the heritable characteristics of a population over time
What is evolution by natural selection?
a change in the allele frequency in a population over time
What are the two parts of cell theory?
1. all organisms are composed of cells
2. all cells arise from existing cells
What is a population?
a group of individuals of the same SPECIES living in the SAME AREA at the SAME TIME
What is a trait?
a distinguishing feature of an organism
What is natural selection?
the process by which individuals with certain heritable traits are better able to survive and reproduce compared to other members of the population; process by which these individuals are naturally selected
What is genetic drift?
a change in the frequency of an allele due to a random sampling
What is gene flow?
is the transfer of alleles from one population to another population through immigration of individuals.
What is sexual selection?
a type of natural selection that favors individuals who have a combination of heritable traits that are most useful in obtaining a mate
What is a mutation?
a heritable change in the genetic material of an organism
What is fitness?
ability to produce offspring relative to other individuals
What is adaptation? (noun)
heritable trait that increases fitness of a particular individual in a particular environment
What is adaptation? (verb)
an evolutionary process; alters an organism’s phenotype to enhance its ability to survive in its particular environmental niche
What is a gene?
a length of DNA that encodes for a protein
What is an allele?
a version of a gene
What is a chromosome?
a gene-carrying structure consisting of a molecule of DNA and associated with histone proteins
What is a genotype?
the genetic makeup of an individual
What is a phenotype?
the physical characteristics of an organism
What is a species? (3 parts)
an identifiable group that is distinct in
1. appearance, behavior and habitat
3. evolutionarily indépendant
What is the central dogma?
DNA is transcribed into RNA and RNA is translated into proteins which make up traits
What is transcription?
the process of making an equivalent RNA copy from a DNA sequence
What is translation?
when the genetic code is decoded to produce a specific amino acid sequence that encodes for a protein
What is DNA synthesis?
natural creation of DNA molecules
What is mitosis?
when the replicated chromosomes are divided for placement into two new daughter nuclei with identical chromosomes
What is meiosis?
replication results in 4 daughter cells each with half the number of chromosomes from the parent cell
What is the definition of a homozygous?
identical pairs (AA or aa)
What is the definition of a heterozygous?
one dominant and one recessive allele (Aa or aA)
What is gene linkage?
physical association of genes on a chromosome
What are the 5 mechanisms of genetic change?
1. Natural selection
2. Genetic Drift
3. Gene flow
5. Non-random mating