Author Question: What usually causes Down syndrome? A. Maternal infection during early pregnancy B. Fertilization ... (Read 82 times)

Arii_bell

  • Hero Member
  • *****
  • Posts: 596
What usually causes Down syndrome?
 
  A. Maternal infection during early pregnancy
  B. Fertilization of an ovum containing an abnormal number of chromosomes
  C. An interaction of hereditary and environmental factors
  D. An abnormal gene transmitted by Mendelian inheritance

Question 2

A __________ is a set of HLA genes on one chromosome.
 
  A. karyotype
  B. haplotype
  C. plasmid
  D. polar body



nmyers

  • Sr. Member
  • ****
  • Posts: 336
Answer to Question 1

B

Answer to Question 2

B



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.

Did you know?

Oliver Wendell Holmes is credited with introducing the words "anesthesia" and "anesthetic" into the English language in 1846.

Did you know?

There are 20 feet of blood vessels in each square inch of human skin.

Did you know?

Alcohol acts as a diuretic. Eight ounces of water is needed to metabolize just 1 ounce of alcohol.

Did you know?

The immune system needs 9.5 hours of sleep in total darkness to recharge completely.

For a complete list of videos, visit our video library