Patterns of Inheritance II Chapter 21

Question 1

Draw a picture of a recessive hereditary chart

Answer 1

two unaffected parents have an affected child

Question 2

Draw a picture of a dominant hereditary chart

Answer 2

two affected parents have an unaffected child

Question 3

Autosomal recessive. Caused by defective chloride ion channel which prevents chloride ions, sodium ions, and water from passing through the membrane. Leads to build up of thick mucus in bronchial tubes and pancreatic ducts.

Answer 3

Cystic fibrosis

Question 4

Autosomal dominant. Caused by a mutation in which multiple copies of glutamic acid cause clumping inside neurons. Symptoms begin later in life and include uncontrolled movements, dementia and speech impairment

Answer 4

Huntington disease

Question 5

Autosomal recessive. Caused by the lack of a lysosome enzyme. The lack of this enzyme allows lipids to build up in the brain and cause developmental and sensory defects.

Answer 5

Tay-Sachs disease

Question 6

Autosomal dominant. Caused by a defect in the production of an elastic connective tissue called fibrillin. Causes defects in body structures such as eyes, limb bones, and blood vessel walls

Answer 6

Marfan syndrome

Question 7

___________ traits, such as skin color and height, are governed by several sets of alleles. The result is a continuous variation of phenotypes.

Answer 7

polygenic

Question 8

______________ traits are subject to environmental influences. Examples include schizophrenia, autism (not mentioned in the book), allergies and alcoholism.

Answer 8

multifactorial

Question 9

__________ occurs when a single, mutant gene affects two or more distinct and seemingly unrelated traits. An example is Marfan Syndrome, in which symptoms include long limbs, weakened aorta and poor eyesight.

Answer 9

pleiotropy

Question 10

Inheritance of altered or defective genes responsible for many human diseases.

Answer 10

Genetic Disorders

Question 11

An individual who carries the allele for a recessive trait but does not express it because it is paired with a dominant allele.

Answer 11

Carriers

Question 12

Two affected parents can have unaffected children if both are heterozygotes
Usually does not skip generations
More individuals are affected in general

Answer 12

Autosomal dominant

Question 13

Two unaffected parents can have affected offspring if both heterozygous
If parents are both affected, they can only have affected children
Affected individuals can skip generations
Not many individuals are affected in total

Answer 13

Autosomal Recessive

Question 14

Two alleles being dominant in heterozygotes is an example of what?

Answer 14

Co-dominance

Question 15

A gene can having several possible alleles (instead of only 2)

Answer 15

Multiple-Allele Inheritance

Question 16

Located on the x sex-chromosome
can be either dominant or recessive

Answer 16

x-linked inheritance