Studied by 44 peopleHow did Gregor Mendel get into the study of heredity?
Being in charge of a monastery garden
What plant did Gregor Mendel use to preform his experiments?
Peas
What does the part of the plant that produces pollen contains what gametes?
Male Reproductive Cells; Sperm
The female portion of the flower contains what gametes?
Eggs
What is the process in which male and female reproductive cells join?
Fertilization
What type of pollination do pea flowers usually preform?
Self-Pollination
What process include sperm cells in pollen fertilizing the egg-cells in the same flower?
Self-Pollination
What type of breeding includes plants producing offspring identical to themselves?
True-Breeding
In Gregor Mendel's pea plants what traits were the basis of his experiments?
Tall vs Short and Green Seeds vs Yellow Seeds
What type of pollination was Gregor Mendel attempting to preform with the pea plants?
Cross Pollination
How did Gregor Mendel prevent self pollination in the pea plants?
By cutting away the pollen producing male reproductive structures
How did Gregor Mendel cross pollinate the pea plants?
By dusting the pollen from another plant onto the flower
What are the original pair of plants called?
The P generation
What does the P in the P generation stand for?
Parental
What are the offspring of the P generation?
The F1 genreation
What does the F in the F1 generation stand for?
First Filial
What does Fillia/us mean in Latin?
Son/Daughter
What are the offspring of crosses between parents with different traits?
Hybrids
What were the seven traits Gregor Mendel studied?
Seed Shape, Seed Color, Seed Coat Color, Pod Shape, Pod Color, Flower Position, and Plant Height
What happened to the characters of the parents after the cross in the F1 generation?
The character of one parent was expressed while the other seemed to have disappeared
What was the first conclusion Gregor Mendel reached after his set of experiments?
Biological inheritance is determined by factors that are passed from generation to the next
What do scientists today call the chemical factors that determine traits?
Genes
What are the different forms of a gene called?
Alleles
What was Gregor Mendel's second conclusion after his set of experiments?
The principal of dominence
What is the principal of dominence?
Some alleles are dominant and some are recessive
In what case will a recessive allele be expressed?
When the dominant allele isn't present
What allele was dominant in pea plant height?
Tall
What allele was recessive in pea plant height?
Short
What allele was dominant in pea plant seed color?
Yellow
What allele was recessive in pea plant seed color?
Green
How did Gregor Mendel answer the question, "Had the recessive alleles disappeared or were they still present in the F1plants?"?
He allowed all of the hybrid plants to produce an F2 generation
How did Gregor Mendel make the F2 generation?
By crossing the F1 generation with itself
What does the F in F2 stand for?
Second Filial
What discovery did the crossing of the F1 generation spark?
The traits controlled by the recessive alleles had reappeared
What is Gregor Mendel's law of segregation?
Each individual that is a diploid has a pair of alleles for a particular trait
What is Gregor Mendel's law of independent assortment?
The alleles of two (or more) different genes get sorted into gametes independently of one another
What principals can be used to predict the outcomes of genetic crosses?
The Principals of Probability
The gene combination that might result from a genetic cross can be determined by drawing a...
Punnet Square
What are organisms with two identical alleles for a particular trait?
Homozygous
What are organisms with two different alleles for a particular trait?
Heterozygous
If a pea plant has a TT allele and another has tt what is the percent that the cross will result in a tall plant?
100% Tall
If a pea plant has a TT allele and another has Tt what is the percent that the cross will result in a Tt allele?f
50% Tt
If a pea plant has a tt allele and another has Tt what is the percent that the cross will result in a short plant? What about a Tt allele?
50% Short 50% Tt
What are the cases in which some alleles are neither dominant nor recessive?
Incomplete Dominance and Co-dominance
What are the cases in which some traits are controlled by multiple alleles or multiple genes?
Multiple Alleles and Polygenic Traits
What is incomplete dominance?
The hererozygous phenotype is somwhere in betweent eh two homozygous phenotypes (Ex. Red Flower (RR) White Flower (rr) Pink Flower (Rr))
What is codominance?
Both alleles contribute to the phenotype; both alleles are expressed separately (Ex. White Chicken (CC) Black Chicken (cc) Speckled Chicken (Cc))
What are multiple alleles?
More than two possible alleles exist in a population
What are polygenic traits?
Traits that are controlled by two or more genes
What is a cell that contains both sets of homologous chromosomes?
Diploid
How are diploid chromosomecounts sometimes represented?
2N
Gametes are what type of cell?
Haploid
How many sets of chromosomes do haploid cells have?
1
How are haploid chromosome counts sometimes represented?
N
How many chromosomes do human diploid cells have?
46
How many chromosomes do human haploid cells have?
23
What is meiosis?
The process in which a diploid cell divides into four haploid cells
How is meiosis pronounced?
MY-osis
What occurs during interphase 1 of meiosis?
Cells undergo a round of DNA replication, forming duplicate chromosomes
What occurs during prophase 1 of meiosis?
Each chromosome pairs with its corresponding homologous chromosome to form a tetrad
What occurs during metaphase 1 of meiosis?
Spindle fibers attach to the chromosomes
What occurs during anaphase 1 of meiosis?
The fibers pull the homologous chromosomes toward opposite ends of the cell
What occurs during telophase 1 and cytokenisis of meiosis?
Nuclear membranes form and the cell separates into two cells
What occurs during prophase 2 of meiosis?
Meiosis 1 results in two haploid daughter cells each with half the number of chromosomes as the original cell
What occurs during metaphase 2 of meiosis?
The chromosomes line up similarly to the metaphase stage of meiosis
What occurs during anaphase 2 of meiosis?
The sister chromatids separate and move towards opposite ends of the cell
What occurs during telophase 2 and cytokenisis of meiosis?
Four haploid daughter cells result
In male animals the haploid gametes produced by meiosis are called...
Sperm
In female animals the haploid gametes produced by meiosis are called...
Eggs
What is the major difference between mitosis and meiosis
Mitosis results in the production of two genetically identical diploid cells, whereas meiosis produces four genetically different haploid cells
A diploid cell that divides by mitosis gives rise to...
Two identical diploid daughter cells
A diploid cell that divides by meiosis will divide how many times?
Twice
A diploid cell that divides by meiosis gives rise to...
Four genetically different haploid daughter cells
How do sexually producing organisms produce gametes?
Meiosis
Does asexual reproduction involve mitosis or meiosis?
Mitosis
Who discovered the principal of linkage?
Thomas Hunt Morgan
In what year was the principal of linkage first discovered?
1910
How did Thomas Hunt Morgan figure out gene linkage?
By researching fruit flies
Each chromosome is...
A group of linked genes
What sorts independently chromosomes or individual genes?
Chromosomes
What are gene maps?
A map of the relative locations of genes on a chromosome
How are gene maps produced?
Recombination Rates
What are recombination rates?
Rates that measure the frequencies of crossing over between genes
What is selective breeding?
Allowing only animals with desired characteristics to produce the next generation
How do humans use selective breeding?
By taking advantage of naturally occurring genetic variation in plants, animals, and other organisms, to pass desired traits on to the next generation of organisms
What is hypbridization?
Crossing dissimilar individuals to bring together the best of both organisms
Which is hardier hybrids or their parents?
Hybrids
What is inbreeding
The continued breeding of individuals with similar characteristics
What is inbreeding used for?
To maintain the desired characteristics of a line of organisms
What is the risk of inbreeding?
The crossing of the two genetically similar organisms can lead to a higher likelyhood of birth defects
How can breeders increase genetic variation in a population?
Inducing Mutations
What are the ultimate sources of genetic variation?
Genetic Mutations
What are mutations?
Inheritable changes in DNA
How do breeders increase the mutation rate?
By using radiation and chemicals
What is polypoidy?
Organisms having extra sets of chromosomes
Who tolerates polypoidy better animals or plants?
Plants
How are changes made to DNA?
Extracting DNA froms cells, cutting it into smaller pieces, identifying the sequence of bases in a DNA molecule, and replicating it
What is genetic engineering?
Making changes in the DNA code of a living organism
How do biologists extract DNA?
Opening cells and separating the DNA from the other cell parts
How is DNA cut into easier to understand pieces?
Using restriction enzymes the DNA is cut in specific nucleotide sequences
Note
Flashcard