5.6

Question 1

1. How does the law of segregation account for genetic variation?
2. How does independent assortment result in genetic variation?
3. What is nondisjunction and how does it contribute to genetic variation?
4. How does fertilization in sexually reproducing organisms lead to genetic variation?
5. What effect does chromosomal inheritance have on genetic variation and human disorders?

Answer 1

1. The segregation of parental alleles into gametes provides opportunity for more varied combinations of alleles when fertilization occurs.
2. The assortment of genes independently into gametes provides more possible gene combinations when fertilization occurs.
3. Nondisjunction is the failure of chromosomes to fully separate during the formation of gametes. This results in too many or too few chromosomes in the sex cells.
4. Random fertilization leads to genetic variation in offspring of sexually reproducing organisms.
5. Certain human genetic disorders can be attributed to chromosomal inheritance and can result in genetically varied offspring.

Question 2

• The law of segregation explains the…

Answer 2

separation of alleles during gamete formation.

Question 3

Independent assortment suggests that genes for two or more traits will be…

Answer 3

sorted into gametes independently; genes are not linked.

• Inheritance of each gene is random and not connected to inheritance of any other gene.

Question 4

• Mutated alleles can be inherited.
• Chromosomes can carry mutated alleles.
• The law of segregation and independent assortment explain how mutated alleles can be randomly distributed into gametes.
  Mutations contribute to genetic diversity in offspring.
  Mutations can manifest as genetic disorders when the variations negatively affect the functioning of the offspring.

Question 5

Nondisjunction is the…

Answer 5

failure of chromosomes to fully separate during the formation of gametes.
* This results in too many or too few chromosomes in the sex cells.

Question 6

What’s a gamete?

Answer 6

It’s an one of the two haploid cells that fuse during fertilization to form a diploid zygote.

Question 7

• Each gamete carries only one allele for each gene therefore each gamete receives only one…

Answer 7

parental allele

Question 8

Segregation of parental alleles into gametes provides opportunity for more…

Answer 8

varied combinations of alleles when fertilization occurs.

Question 9

Assortment of genes independently into gametes provides more…

Answer 9

possible gene combinations when fertilization occurs.

* Ex. pea color and pea shape

Question 10

• Random fertilization refers to the concept that…

Answer 10

any of the genetically unique sperm created by a male can join with any of the genetically unique eggs created by a female.

This will produce offspring with a genetically unique combination of chromosomes.

Question 11

1. How can chromosomal inheritance show patterns of transmission of genes from parents to offspring?
2. How can human genetic disorders be based on chromosomal inheritance?
3. How can we use visual representations to analyze changes or disruptions in chromosomal inheritance?

Question 12

How can some genetic diseases come about?

Answer 12

A single mutated allele or specific chromosomal change that can be passed from parent expression

Question 13

How can patterns of gene transmission be analyzed?

Answer 13

It can be analyzed by parent to offspring inheritance

Question 14

What is true about mutations and mis-formations in gametes?

Answer 14

It can be a result of passiing down faulty traits from the parent(s), but it can also be a result of a new mutation of misformation that wasn’t found in either of the parents