BIO 130 Test 2 Flashcards
(127 cards)
What is the process where homologous chromosomes pair up during prophase 1 of meiosis
Synapsis
Genetic process that occurs during meiosis when homologous chromosomes exchange genetic material
Crossing Over
A process that restructures part of a genome by exchanging genetic material between DNA molecules
Recombination
A breeding experiment that involved reversing the sexes of parents in a cross to determine the role of parental sex in inheritance
Reciprocal cross
Parental Generation, 1st generation, 2nd generation
P, F1, F2
A genetic theory that explains how phenotypic traits are passed down through generations
Particulate Inheritance
Pairs of alleles, or genes are separated into reproductive cells during meiosis
Principle of segregation
trait or gene that is most influential
Dominant
Trait or gene that is less strong, only shows through if it is homozygous
Recessive
two or more traits are fully expressed and neither is dominant or recessive
Codominant
A genetic phenomenon where a heterozygote phenotype is more extreme than either of its parents phenotypes
Overdominant
Different genes and their corresponding trait are separated independently during the development of reproductive cells
Principles of Independent assortment
A characteristic that is determine by genes located on the sex chromosome
Sex-linked trait
A genetic phenomenon where a single DNA variant, or gene, affects multiple traits that may seem unrelated.
Pleiotropy
A genetic phenomenon where the expression of one gene is modified by the expression of one or more other genes.
Epistasis
What are the three purposes of mitosis we discussed in class?
Growth, repair, and asexual reproduction
Why is it important to have regulation checkpoints in the cell cycle?
They act at control mechanisms to make sure the cell is fully grown and ready to divide into two cells
What is the evolutionary explanation for sexual reproduction?
Provides genetic diversity within a population
In what two ways does meiosis increase genetic variation?
Crossing over and Independent Assortment
What are the characteristics of a good model organism for genetic studies?
-a large natural population with a wide range of genetic variations
-a short generation time allowing for rapid observations of new mutations
-easily identifiable phenotypic traits linked to genetic variations
-well established genetic tools for manipulating and analyzing the genome
-a species with a high level of genetic diversity that is also convenient to study in a laboratory setting
Explain Mendel’s model of particulate inheritance
Genetic traits are passed from parent to offspring as discrete units called “particles” meaning that traits are not blended together but inherited as distinct entities
Cell cycle and phases
A series of events that a cell goes through to divide into two new daughter cells
-G1
-S
-G2
-Interphase
-Prophase
-Metaphase
-Anaphase
-Telophase
-Cytokinesis
Mitosis
A process where a single cell divides into two genetically identical daughter cells
Meiosis
A type of cell division that occurs in sexually reproducing organisms to produce gametes, or sex cells like eggs and sperm