Science chapter 5 Flashcards
Genetics
what is the definition of genetics?
The passing of genetic traits from parents to offspring.
Where and what year was Gregor Mendel born?
Austria, 1822
What is Gregor Mendel’s nickname?
“Father of Genetics”
What did Gregor Mendel study?
Pea Plants
What are the five reasons that Gregor Mendel studied pea plants?
- They could cross-pollinate
- They could self-pollinate
- They grew quickly
- They had many different observable characteristics
- They could grow true breeding plants
Explain what happened in Gregor Mendel’s experiment with pea plants.
This is short answer #1
Gregor noticed that tall pea plants always had tall offspring, and vice versa. He wondered what would happen if he combined tall with short. To his surprise, all of the offspring (F1) were tall. This is where he realized that some traits were dominant (Law of Dominance). He wondered what would happen if he combined the F1 generation (look tall but carry short gene) to create more offspring. The result was that in the F2 generation, there was always a 3:1 ratio between the dominant and recessive trait.
What was the ratio that Mendel noted was always there between the dominant and recessive trait?
A 3 to 1 ratio.
What is the definition of alleles?
A variation of a gene in letter form.
If you have two alleles that are the same for a particular trait you are what?
You are said to be homozygous (or pure)
If you have two alleles that are different for a particular trait you are what?
You are said to be heterozygous (or hybrid)
What is the definition of probability?
The chance of something happening.
What is the difference between phenotype and genotype.
A phenotype is the way that genes appear in real life, or physical appearance like blue eyes and blond hair (qualitative). A genotype is the letter combination that gives you certain traits like BB, bb, and Bb
What are three rules of incomplete dominance?
- The traits blend or mix together to form a new trait (ex. blue and yellow = green).
- Neither trait dominates over the other.
- There are no lower case letters allowed.
What is one example of a plant that has incomplete dominance?
A Japanese four o’clock flower
What is the big difference between incomplete dominance and co-dominance?
The two traits are both visible in the phenotype instead of the two traits mixing together in the phenotype.
What is the word that you would use to describe the color of an animal if both colors are visible?
Roan
What is the definition of multiple alleles?
More than two possible alleles can control a trait.