Genetics Section 1 Flashcards
the passing of traits from parent to offspring
heredity
a genetically determined characteristic (e.g., blue eyes)
trait
a priest who lived in a monastery in 19th century and is known as Father of Genetics
Mendel
What question did Mendel have about his garden?
why pea plants have different characteristics (small, tall)
why did Mendel use pea plants?
grew quickly
many different kinds available
able to self pollinate
what is the opening of the pollen tube called
stigma
what part of plant contains the pollen tube
style
what part of the plant contains the pollen
stamens
what part of the plant contains the egg
ovule
explain pollination and fertilization in pea plants
pollination - pollen reaches the stigma
the pollen releases the sperm to travel down the style
fertilization- egg and sperm join
what was mendel’s first experiment
2 PUREBRED pea plants (one purple one white), cut off anthers to prevent self pollination, took pollen from 1 plant and pollinated the other. Each time the offspring showed the dominant trait. Offspring were all purple (1st generation). Trait that appeared the most is called DOMINANT. Trait that appeared less was RECESSIVE.
what is meant by purebred?
an offspring of many generations that have the same trait (e.g., PP or pp)
Another name for the P generation is ___
parent
Explain self pollination
a self pollinating plant has both male and female reproductive structures in one plant. Anthers (male) can fertilized the ovary (female) through the stigma on the same plant.
Explain cross pollination
pollen from one plant fertilizes the ovary of a flower on another plant by way of wind, insect ( bee)
what did Mendel find when he crossed purebred short plants with purebred tall plants?
he found all tall plants in the F1 generation
when Mendel crossed the offspring (F1 generation) with one another, was the trait for shortness lost? Explain.
No because the F1 generation were carriers for the short trait
Explain Mendel’s 2nd experiment
Mendel allowed the first generation plants from the first experiment to self pollinate (these are purple). The recessive trait appeared in 1 out of 4 offspring (3 purple, 1 white). These offspring are called the second generation or F2.Mendel discovered that each offspring had 2 sets of instructions, each parent donates 1 set.
Through Mendel’s experiments, what conclusions did he come to?
he said that the individual factors or sets of genetic info must control the inheritance of traits in peas. These factors that control each trait come in pairs, one from each parent. One factor can hide the other.
If a trait is dominant, what does it mean and show the different ways it is represented.
a trait that shows up in the organism when the allele is present TT or Tt
if a trait is recessive, what does this mean and show how it is represented
a trait that does not show up when the dominant trait is present tt
Mendel studied 7 different traits in pea plants. Under what conditions would the recessive form of 1 of these traits appear?
if both parents carried the recessive trait.
what is a hybrid?
an organism that has 2 different alleles for a trait Tt
