Mendel's Law of Inheritance

Question 1

Inheritance

Answer 1

the principles regarding how traits are passed on to offspring.

[https://youtu.be/OhYOfTczCk4?si=_kcFcVxp5ohnlfle](https://youtu.be/OhYO

Question 2

Punnett Square

Answer 2

A chart used to make predictions about the likelihood of a trait being passed from parent to offspring.

Question 3

The Law of Dominance

Mendals 3rd law

Answer 3

Mendel found that for 2 alleles for a gene, the dominanent trait is always expressed or shown by the organism if it is present, because it masks the recessive allele.

The recessive allele is only expressed when both alleles are recessive.

Question 4

alleles

Answer 4

a specific copy of a gene

Question 5

genotype

Answer 5

the genetic makeup of an individual.

example

the mom and dad both have 23 pairs of chromosomes for a total of 46 chromosomes.

each parent contributes 23 chromosomes , therfore the offspring inherit two coppies of each gene, one from each parent.

Question 6

homozygous

Answer 6

If a chromosome conatiains 2 alleles that are the same, the genotype is homozygous.

Question 7

heterozygous

Answer 7

a genotype inwhich the chromosome contains two different alleles.

Question 8

phenotype

Answer 8

the expression of the genes for that trait.

alleles that are present and visible in an organism determine the phenotype.

example:

visible traits ; eye color ,hair color, seed color

unseen traits; blood type

Question 9

Meisosis

Answer 9

traits are passed from parents to offspring through gametes (eggs or sperm)

each gamete has passes 1 chromosme from their pair of chromosomes and one copy of a gene.

Question 10

Meiosis

Answer 10

Both the sperm cell and the egg cell each carry 23 chromosomes. Chromosomes are threadlike structures consisting of tightly wound DNA molecules. The sperm and egg cells combine to form a zygote during fertilization, which carries all 46 chromosomes.

The zygote then starts cell division. It divides into two cells, then into four cells, and then into eight cells, and so forth. Eventually, after many rounds of cell division and growth, it becomes a baby. Generally, when cells divide, they copy the exact chromosome number and then split them into the new cells. Therefore, all the daughter cells have the same chromosome number as their parent cell.

As the zygote at the beginning of its development contains 46 chromosomes, all of its daughter cells (which make up the human body cells) will also have 46 chromosomes. Therefore, after two rounds of cell division following fertilization (which generates four cells), each cell will contain 46 chromosomes.

Question 12

Punnet square

Answer 12

Question 13

Recessive allele

Answer 13

lowercase letter

these traits are masked or hidden if dominant alleles are present

example

pp is a recessive allele

Pp the phenotype of the P will show because it is dominant

Question 14

Dominant allele

Answer 14

uppercase letter

refers to the most powerful trait or the allele of that trait

P is dominant

Pp this has a recessive allele p and dominant allele P. The phonotype of P will show because it is dominant

Question 15

non-Medelian inheritance

Answer 15

Inheritance of traits that do not follow Mendellian patterns of inheritance

Question 16

A pea plant has a dominant homozygous genotype. which of the following letters best represents this genotype?

A. WW
B. Ww
C. ww
D.WX

Answer 16

A. WW

Question 17

Pea plants have seeds that are either green or yellow. Green seeds are dominant to yellow seeds. Two pea plants that are heterozygous for seed color are crossed. What percentage of their offspring will have green seeds?

Question 19

Which of the following best describes the expression of alleles?

A. Heritable trait
B. Genotype
C. Phenotype
D. P generation

Answer 19

C. Phenotype

Question 20

Use a Punnet square to show the likely phenotypes of crossing two heterozygous tall pea plants. The allele for tall plants is dominant,

Answer 20

IT is a 3:1 ratio

75 % are dominant tall

25% are recessive short

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