Mendelian Genetics

Question 1

Gregor Mendel

Answer 1

Gregor Mendel, the “Father of Genetics,” discovered the fundamental laws of heredity and discovered traits through experiments with pea plants in the 19th century.

Question 2

Mendel Experiments

Answer 2

Mendel performed controlled crosses with true-breeding pea plants, ensuring consistent traits by maintaining controlled variables like water, sun, and soil conditions.

Question 3

Alleles

Answer 3

Different form of the same gene, expressed as a letter

Question 4

Dominant alleles

Answer 4

Expressed as a capital letter, and will always express itself when present

Question 5

Recessive allele

Answer 5

Expressed as a lower case, and isn’t always expressed as a trait, it’s inactive but still present

Question 6

Law of Dominance

Answer 6

The Law of Dominance states that dominant alleles always express their traits, while recessive alleles remain hidden unless both alleles are recessive (e.g., tall “T” dominates over short “t”).

Question 7

What is a genotype

Answer 7

The combination of a given gene

Question 8

What is a phenotype

Answer 8

The appearance of a the gene/ trait

Question 9

What is the law of segregation

Answer 9

The Law of Segregation states that alleles separate during gametogenesis, with each parent passing only one allele to their gamete cells, which recombine at fertilization to determine the offspring’s traits.

Question 10

Homozygous alleles

Answer 10

Homozygous alleles refer to traits where both alleles are the same, either both dominant (e.g., TT) or both recessive (e.g., tt).

Homozygous dominant: two dominant alleles, AA

Homozygous recessive; two recessive alleles, aa

Question 11

Heterozygous alleles

Answer 11

Heterozygous alleles refer to traits expressed with both a recessive and dominant allele, Aa

Question 12

Law of independent assortment

Answer 12

Allele are inherited independently of each other because of mixing up the alleles through cross over and random separation

Question 13

Beyond Mendelian Genetics (exceptions to his principal)

Answer 13

Mendels principle states that only the dominant alleles in a heterozygous genotype would be expressed, while the recessive wouldnt (only one allele would be expressed). However the explanation includes..

Codominance
Incomplete Dominance
Multiple Alleles
Polygenic Traits

And the expectation mentioned above involve heterozygous geno type but both alleles are expressed

Question 14

Incomplete dominance

Answer 14

The heterozygous genotype produces a phenotype that falls between the dominant trait and recessive trait

Question 15

Codominance

Answer 15

Neither allele of a geno is dominant over the other, they are both expressed equally

Question 16

Mendelian laws (law of inheritance)

Answer 16

1) law of segregation
2) law of independent assortment
3) law of complete dominance