Question

i. chromosomes and phenotype (7.1)
a. ______ copies of each autosomal gene affect phenotype

1. most human traits are result of ____________ genes
2. many human genetic ____________ also caused by autosomal genes

a. chance of having disorder can be ____________
b. use same principles as ____________ did
b. disorders caused by ____________ alleles

1. some disorders caused by recessive alleles on autosomes
2. must have ____ copies of __________ allele to have disorder

a. disorders often appear in offspring of parents who are ____________
b. __________ __________ - recessive disorder that affects sweat glands and mucus glands.

1. a person who is heterozygous for disease is called a ____________ - does not show disease symptoms

heterozygous parent (cc), carrier
c c

Explanation:

This question is about genetics, specifically autosomal genes and genetic disorders. In biology (a subfield of Natural Science), we study how genes on autosomes affect phenotype and cause disorders. For part A, humans have two copies of each autosomal gene (since autosomes are in pairs), most traits are polygenic (multiple genes), and many genetic disorders are from autosomal genes. The chance of a disorder can be predicted, using Mendel's principles. For part B, recessive alleles cause some disorders; you need two copies of the recessive allele. Parents are often carriers (heterozygous), like in cystic fibrosis (a recessive disorder affecting glands). A heterozygous person is a carrier.

Answer:

A.

1. Two copies of each autosomal gene affect phenotype.
2. Most human traits are result of polygenic genes.
3. Many human genetic disorders also caused by autosomal genes.

a. Chance of having disorder can be predicted.
b. Use same principles as Mendel did.

B.

1. Disorders Caused by Recessive Alleles.
2. Must have two copies of recessive allele to have disorder.

a. Disorders often appear in offspring of parents who are carriers (heterozygous).
b. Cystic Fibrosis - recessive disorder that affects sweat glands and mucus glands.

1. A person who is heterozygous for disease is called a carrier - does not show disease symptoms.