Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
12 Cards in this Set
- Front
- Back
|
A trait is ________.
During cell division, chromosomes are ____ and then distributed to daughter cells. ____ are passed from parent to offspring in these ____. At one time, it was believed that traits of parents were ____ in offspring. This isn't accurate at all. The first clues to understanding inheritance came from ____ ____, an outstanding geneticist in the ____ ____. He used garden pea plants to study how traits were ________. After gathering information on more than #____ pea plants, Mendel suggested several hypotheses to explain the inheritance of traits. |
any characteristic that can be passed from parents to offspring
replicated Traits, chromosomes blended George Mendel, late 1800s passed from one generation to another 20, 000 |
|
|
The structure of the pea flower allowed Mendel to manipulate ____.
Pea plants contain both ________ within the same flower. So, he could simply allow them to ____, or alter them so that they had to ____. If a plant (or any other organism) receives the same genetic traits from both its parents, it is called a ____. So, the plants the he allowed to self-pollinate produced ____ pea plants. He altered some of the pea plants by removing the ____ from them, and transferring the ____ by hand (from one flower to another). Mendel ____ plants, producing ____. A hybrid is ________. |
fertilization
male and female gametes self-pollinate, cross-pollinate purebred purebred anthers, pollen crossbred, hybrids any organism that receives different forms of a genetic trait from each parents |
|
|
Mendel began his experiments using two ____ groups of ____ plants.
He called this generation the ____, or ____, generation. He named the second generation the ____, or ____ generation. The offspring of the F1 generation were named the ____, or ____. Mendel crossed ____ pea and ____ pea parents. Surprisingly, he found that all of the ____ peas were ____. (According to the blending theory, they would all have been ____) After allowing the ____ peas, to ____, he found that #____ were ____ and #____ were ____ (no ____) So, blending was ________ |
different, purebred
parental, P First filial, F1 second filial, F2 yellow, green F1, yellow, yellow-green F1, self-fertilize, 3/4 were yellow, 1/4 were green not going on |
|
|
Mendel repeated these crosses and observed many other traits like height, flower color, pea shape, etc... He continually found the ____ results.
The ____ generation always showed ____ ____ form of each trait. He defined each form of the trait as either ____ or ____. A dominant form appeared in the ____ generation. A recessive form did not appear in the ____ generation. In the F2 generation, he always found ____ form of each trait. #____ of the ____ generation showed the dominant trait, and #____ of the ____ showed the recessive trait. |
same
F1, only one dominant or recessive F1 F1 two 3/4, F2, 1/4, F2 |
|
|
After crossing the generations, Mendel hypothesized that each trait is controlled by a distinct "factor" (which we know today is ____)
He decided that for every ____, an organism must carry a ____ of factors-- the offspring receives ____ from each parent. Genes are ________. Most organisms have ____ copies of every gene and ____, one from each parent. The different forms of genes are called ____. pea color in pea plants is controlled by ____ gene with ____ allele -- ____ and ____. If an organism has two different alleles for a trait, ____ is expressed, or visible. A dominant allele is form of a gene that is ________. A recessive allele is a form of a gene that is ________-- it is ____ |
gene
trait, pair, one sections of chromosomes that code for a trait two, chromosomes alleles one, two, yellow and green one fully expressed even if another allele is present not fully expressed when paired with a dominant allele, hidden |
|
|
By (year)____, ____ ____ had outlined the ____ theory of ____.
This theory states that the ________. ____ genes are located on ____ chromosomes. As you work with traits and inheritance, ____ will be used to represent alleles. The allele for yellow peas, the ____ trait, is represented by a capital Y. The allele for green peas, the ____ trait, is represented by a lowercase y. (Same letter is used since ________) |
1903, Walter Sutton, chromosome, heredity
material of inheritance is carried by the genes in chromosomes specific, specific letters dominant recessive both yellow and green are alleles for the same gene |
|
|
The genetic makeup of an organism is called its ____.
The genotype includes ____ ____ in a homologous pair of chromosomes. The genotype of a purebred yellow pea plant is YY. A hybrid is written Yy. The phenotype of an organism is the ____ ____ of the trait. The genotypes YY and Yy show a ____ phenotype. The genotype yy shows a ____ phenotype. |
genotype
both genes outward expression yellow, green |
|
|
genotypes can be either ____ or ____.
An organism in which the two alleles in a gene pair are identical is called ____. An organism in which the two alleles for a particular trait are different is called ____ |
heterozygous or homozygous
homozygous heterozygous |
|
|
Law of Segregation::
Gene pairs separate when ____ form (during ____). because of ____, ____ of an organism's gametes contain #____ gene from a ____ ____, and half of the gametes contain the other gene. |
gametes, meiosis
segregation, half, one, homologous pair |
|
|
Law of Independent Assortment::
After Mendel began to study more than one ____ at a time, he noticed that traits are ____ ____. Gene pairs segregate into gametes ____ and ____ of each other. (Without independent assortment, you couldn't have your father's eyes and your mother's nose.) |
trait, inherited independently
randomly, independently |
|
|
Law of Dominance::
the ____ allele is always expressed, while the ____ allele can be ____. In pea plants, heterozygous for flower colors, the ____ purple color controls the ____. The other allele in the pair, the allele for white flowers ____ ____ affect the phenotype. A recessive allele is expressed only when ________ |
dominant, recessive, hidden
dominant, phenotype does not the organism has no copy of the corresponding dominant allele |
|
|
Scientists use ____ to predict the ____ and ____ in breeding experiments.
Scientists use a ____ ____ to make predictions about genetics. A punnett square is a ________ -- shows ____, not ____ ____. |
probability, genotypes, phenotypes
Punnett Square grid for organizing genetic information, probabilities, actual results |
