Chapter 9 Flashcards
(56 cards)
The transmission of traits from one generation to the next is known as?
Heredity
The scientific study of heredity is known as?
Genetics
When did the study of genetics begin and with who?
1860s and Gregor Mendel
A heritable feature that varies among individuals within a population, such as flower color in pea plants or eye color in humans
Character
A variant of a character found within a population, such as purple flowers in pea plants or blue eyes in people
Trait
What did Mendel view as the most important advantage of experimenting on pea plants?
Mendel could strictly control the pea plants reproduction
***To ensure accurate results, Mendel covered a flower with a small bag so that no pollen from the other plants could reach the carpel (egg producing organ)
When he wanted to fertilize one plant with pollen from a different plant, he pollinated the plants by hand to always to be sure of the parentage
The offspring of parents of two different species of or two different varieties of one species; the offspring of two parents that differ in one more inherited traits; an individual that is heterozygous for one or more paired genes
Hybrids
The cross-fertilization of two different varieties of an organism or of two different species; also called hybridization
Cross
The parent individuals from which offspring are derived in studies of inheritance. Purebred parents are also called this.
P generation
The offspring of two parental individuals.
What the hybrid offspring is known as.
F1 Generation
Imagine you have 2 purebred dogs, one male and one female. Use the correct genetic names to describe the next two possible generations.
The purebred parents are the P generation. Their puppies are the generation. If those puppies are bred with each other, they would produce the generation.
An alternative version of a gene
Allele
Genes come in different versions called _______. What term describes the condition where the two copies are identical? What term describes the condition where the two copies are different?
Alleles; homozygous; heterozygous
If two plants have the same genotype, must they have the same phenotype?
Yes
If two plants have the same phenotype, must they have the same genotype?
No. One could be homozygous for the dominant allele, whereas the other is heterozygous.
You carry two alleles for every trait. Where did these alleles come from?
One is from your father through his sperm and one is from your mother through her egg.
A mating of individuals that are heterozygous for the character being followed
Monohybrid Cross
A mating of individuals differing at two genetic loci
Dihybrid cross
A general rule of inheritance that states that when gametes form during meiosis, each pair of alleles for a particular character segregates independently of each other pair
Independent Assortment
If you mate a chocolate Lab with a black Lab of unknown genotype and you end up with a litter of three black puppies, do you know for certain the genotype of the black parent?
No. It could be BB and would always produce black puppies or it could be Bb and just happened to have three black puppies in a row. Breeding more puppies would increase confidence in the result.
A man and a woman who are both carriers of cystic fibrosis have three children without cystic fibrosis. If the couple has a fourth child, what is the probability that the child will have the disorder?
1/4 (The genotypes and phenotypes of their other children are irrelevant.)
Peter is a 28-year-old man whose father died of Huntington’s disease. Peter’s mother shows no signs of the disease. What is the probability that Peter has inherited Huntington’s disease?
50%
What do the terms gene and allele have in common?
Both could refer to the same DNA sequence
