Heredity And Environment Unit Exam

When a zygote splits, the two identical, independent clusters that develop become:

• Dizygotic twins

• Monzygotic twins

• Fraternal twins

• Trizygotic twins

In scientific research, the best way to separate the effects of genes and the environment is to study:

• Dizygotic twins

• Adopted children and their biological parents

• Adopted children and their adoptive parents

• Monozygotic twins raised in different environments

Most of the known genetic disorders are:

• Dominant

• Recessive

• Seriously disabling

• Sex-linked

Genes are segments of molecules of:

• Genotype

• Deoxyribonucleic acid (DNA)

• Karyotype

• Phenotype

The potential for genetic diversity is humans is so great because:

• There are approximately 8 million possible combinations of chromosomes

• When the sperm and ovum unite, genetic combinations not present in either parent can be formed

• Just before a chromosome pair divides during the formation of gametes, genes cross over, producing recombinations

• All of the above reasons

Polygenic complexity is most apparent in _______ characteristics.

• Physical

• Psychological

• Recessive gene

• Dominant gene

Babies born with trisomy-21 (Down syndrome) are often

• Born to older parents

• Unusually aggressive

• Abnormally tall by adolescence

• Blind

Some genetic diseases are recessive, so the child cannot inherit the condition unless both parents

• Have Kleinfelter syndrome

• Carry the same recessive gene

• Have XO chromosome

• Have the disease

Dizygotic twins result when:  

• A single egg is fertilized by a sperm and then splits

• A single egg is fertilized by two different sperm

• Two eggs are fertilized by two different sperm

• Either a single egg is fertilized by one sperm or two eggs are fertilized by two different sperm

Molecules of DNA that in humans are organized into twenty-three complementary pairs are called:

• Zygotes

• Genes

• Chromosomes

• Ova

If an ovum is fertilized by a sperm bearing a Y chromosome:

• A female will develop

• Cell division will result

• A male will develop

• Spontaneous abortion will occur

Most human traits are...

• Polygenic

• Multifactorial

• Determined by dominant-recessive patterns

• Both a. and b.

The genes that influence height and skin color interact according to the _______ pattern.

• Nonadditive

• Additive

• Dominant-recessive

• X-linked

X-linked recessive genes explain why some traits seem to be passed from

• Mother to son

• Father to son

• Mother to daughter

• Father to daughter

According the text, the effects of environment on genetic inheritance include

• Direct effects, such as nutrition, climate, and medical care

• Indirect effects, such as the individual’s broad economic, political, and cultural context

• Irreversible effects, such as those due to brain injury

• Everything that can interact with the person’s genetic inheritance at every point in life

The personality trait of inhibition (shyness) seems to be partly genetic. A child who inherits the genes for shyness will be shy

• Under most circumstances

• Only if shyness is the dominant gene

• If the environment does not encourage greater sociability

• If he or she is raised by biological rather than adoptive parents

Laurie and Brad, who both have a history of alcoholism in their families, are concerned that the child they hope to have will inherit a genetic predisposition to alcoholism. Based on information presented in the text, what advice should you offer them?

• “Stop worrying, alcoholism is only weakly genetic.”

• “It is almost certain that your child will become alcoholic.”

• “Social influences, such as the family and peer environment, play a critical role in determining whether alcoholism is expressed.”

• “Wait to have children until you are both middle aged, in order to see if the two of you become alcoholic.”

Genetically, Claude’s potential height is 6’0. Because he did not receive a balanced diet, however, he grew to only 5’9”. Claude’s actual height is an example of a

• Phenotype

• Genotype

• Dominant gene

• Recessive gene

Winona inherited a gene from her mother that, regardless of her father’s contribution to her genotype, will be expressed in her phenotype. Evidently, the gene Winona received from her mother is a(n) _______ gene

• X-linked

• Dominant

• Recessive

• Polygenic

The female will determine the sex of the child. 

• True

• False

Sickle cell anemia involves abnormal blood cells

• True

• False

The only cure for club foot is surgery when the child is first born

• True

• False

The birth defect Turner Syndrome is the lack of the 2^nd X chromosome and only occurs in females

• True

• False

Congenital heart defects occur when the heart forms abnormally after the baby is born.

• True

• False

Tourette children often display tics that can be abrupt and repeated movement

• True

• False

An incomplete formed spinal cord, which cause partial paralysis is known as...

• Down Syndrome

• Spina Bifida

• Cystic Fibrosis

• PKU

Choose one of the following birth defect Spina Bifida or Cystic Fibrosis and explain the following: v      Explain the disease v      How it impacts a child’s life       What are the treatments

Do you think a genetic counselor should tell a couple whether or not they should have children?  Why or why not? 

Imagine you are an adopted child who has received no information about your biological parents.  From you observable characteristics what could you determine about your biological parents?  Explain your reasoning. 

Name five prenatal hazards:

Which is more serious and which is more common: dominant genetic disorders or recessive geneteic disorders?

How can environent influence genetic physical traits, such as height, and psychological traits, such as shyness?

What would you do if you knew you were the carrier of a gene for a serious disease?

"Once there was a king, who had a beautiful, large pure diamond.  There was no other diamond like it in the world.   One day, it became deeply scratched.  The king called his best diamond cutters, “I’ll promise you a great reward if you can remove the imperfection from my jewel.”  But they could not.  The king was very upset. Many months later, a man came to the king.  He promised to make the diamond even more beautiful than it ever had been.  Impressed by the man’s confidence, the king consented.  He watched as the man engraved an exquisite rosebud around the blemish and used the scratch to make its stem". Why can this story be equated with birth defects?         Why should people focus of the abilities of the person?