Chapter 6A Flashcards
What kind of plants did Mendel use in his experiments?
Pea plants (7 straits on photo)
This is the study of the inheritance, or the passing of traits from parents to offspring
Generics
In Mendel’s experiment, was the F1 generation produced from a purebred cross or a hybrid cross?
Purebred cross
Used only tall plants with history of being tall for pollen (sperm) and only short plants for pistols (eggs)
How are alleles for dominant traits represented?
?
An organism with the genotype Aa is
a. hybrid recessive.
b. purebred recessive.
c. hybrid.
d. purebred dominant.
?
(True or False) A cross between a pea plant purebred for inflated pods and a pea plant purebred for constricted pods would produce only inflated-pod offspring.
?
Red apples is an example of a
a. phenotype. c. hybrid characteristic.
b. dominant trait. d. genotype.
?
The allele for arched feet is dominant over the allele for flat feet. Write the genotype of someone who has flat feet.
?
What is the difference between purebred and hybrid?
.
Explain the difference between dominant
alleles and recessive alleles.
?
Explain the relationship between genotype and phenotype.
Phenotype is an organisms physical characteristics (tall, shirt, green, round)
Genotype is an organism’s genes (factors)
Units of heredity are called genes.
Genes
He was a Catholic monk and scientist. He experimented with pea plants to investigate how organisms inherit their traits. He studied 7 different traits….
Gregor Mendel
Mating organisms to test how they inherit traits is called a _____?
Cross
Mendel used tall and short pea plants that were always tall or short. Then he crossed them
Bonus Question?
In plants, the pollen contains the male sperm, and the pistil contains the female egg
Bonus question?
F1 abbreviation
First offspring generation, or “filial,” derived from the Latin word filius, which means “son.”
Mendel Pea Plants
F1 and F2 photo
Purebred cross: T mated a t and only created Tt, all plants were tall because T is dominate
Hybrid cross: Then he mated Tt with Tt, and result was TT, Tt, tT and tt, so 3/4th were tall
Mendel made theories after pea plant experiment. One theory was that the traits he was studying were controlled by _____?
factors.
One factor for each trait was supplied by the pollen, and another factor for each trait was supplied by the egg. Thus, each offspring had two factors for each trait, one from each parent. Sort of like “genes”
Why was Mendel’s theory about “factors” not quite accurate?
He said each parent supplied one “factor”. Truth is diploid organism have two genes (factors) for each trait, one from each parent.
The different forms (factors) of a gene for a particular trait are called _____?
Alleles
T and t are the two alleles for plant height gene
If an organism’s two alleles for a trait are the same, (T, T) or (t, t), the organism is _____ for that trait.
Purebred
If a two alleles for a trait are NOT the same (T,t) then that organism is a _____ for this trait.
Hybrid
Mendel’s other theory suggested each allele for a trait was either dominant or recessive. When a plant had two dominant alleles for a trait, the plant showed the ______ trait. When both alleles in the set were recessive, the plant showed the ______ trait.
Dominant trait (T,T)
Recessive trait (t,t)
The way a plant or any organism looks is called its _______. (Tall, short, yellow, round are all physical characteristics)
Phenotype = physical characteristics
The specific factors (genes) an organism contains are called its ______.
You cant tell by looking at physical characteristics (phenotype)
Genotype
When mating two hybrid organisms, (T,t) with a (T,t), the offspring can have three results:
purebred dominant
hybrid
purebred recessive
Who was called the father of genetics?
Mendel
100 years after his “single trait theory”, scientists learned about genes and DNA.
Examples of Dominant/ Recessive Traits in Humans
Dominant: dimples, roll tongue, unattached earlobes, long eye lashes, cleft chin, thick lips, arched feet, widows peak, farsighted, nearsighted
Recessive: lacks dimples, cannot roll tongue, attached earlobes, short eyelashes, smooth chin, thin lips, flat feet, straight hairline, normal signt
Dominate or recessive
If a person has two dominant alleles for simples he is _____. If he has one dominant allele and one recessive allele, he is _____ for dimples
Purebred
Hybrid
True or False: Recessive traits (t,t) are exhibited only when dominant alleles are not present. As a result, a person without dimples has only recessive alleles.
True
