Chapter 5: Genes, Environment-Lifestyle, and Common Diseases

Chapter 5: Genes, Environment-Lifestyle, and Common Diseases

 

Complete Chapter Questions With Answers

 

Sample Questions Are Posted Below

 

MULTIPLE CHOICE

 

1. The data reporting that sickle cell disease affects approximately 1 in 600 American blacks is an example of which concept?

a.	Incidence	c.	Ratio
b.	Prevalence	d.	Risk

 

 

ANS:  B

Prevalence rate is the proportion of the population affected by a disease at a specific point in time. Thus both the incidence rate and the length of the survival period in affected individuals determine prevalence. The incidence rate is the number of new cases of a disease reported during a specific period (typically 1 year), divided by the number of individuals in the population. A numerical expression representing a part of a larger whole or proportion is considered a ratio. Any factor that increases the chance of disease or injury is considered a risk.

 

PTS:   1                    REF:   Page 165

 

2. The ratio of the disease among the exposed population to the disease rate in an unexposed population is referred to as what type of risk?

a.	Attributable	c.	Causal
b.	Contingency	d.	Relative

 

 

ANS:  D

A common measure of the effect of a specific risk factor is the relative risk. Assuming a factor is the cause of a disease, attributable risk is the amount of risk that is due to that factor. A future event or circumstance that is possible but cannot be predicted with certainty is a contingency risk. The probability of the outcome is termed a causal risk factor.

 

PTS:   1                    REF:   Page 165

 

3. Empirical risks for most multifactorial diseases are based on:

a.	Chromosomal testing	c.	Liability thresholds
b.	Direct observation	d.	Relative risks

 

 

ANS:  B

For most multifactorial diseases, empirical risks (i.e., risks based on direct observation of data) have been derived. The other options are not the basis for determining the empirical risk of most multifactorial diseases.

 

PTS:   1                    REF:   Page 167

 

4. What is the cause of familial hypercholesterolemia (FH)?

a.	Diet high in saturated fats
b.	Increased production of cholesterol by the liver
c.	Reduction in the number of low-density lipoprotein (LDL) receptors on cell surfaces
d.	Abnormal function of lipoprotein receptors circulating in the blood

 

 

ANS:  C

A reduction in the number of functional LDL receptors on cell surfaces causes FH. Lacking the normal number of LDL receptors, cellular cholesterol uptake is reduced and circulating cholesterol levels increase (see Box 5-3). The other options are not the basis for developing familial FH.

 

PTS:   1                    REF:   Page 173 | Box 5-3

 

5. Which risk factor for hypertension is influenced by genetic factors and lifestyle?

a.	Sodium intake	c.	Psychosocial stress
b.	Physical inactivity	d.	Obesity

 

 

ANS:  D

The most important environmental risk factors for hypertension are increased sodium intake, decreased physical activity, psychosocial stress, and obesity. However, obesity is, itself, influenced by genes and the environment.