Which of the following is a symptom of Down syndrome quizlet?

Which of the following is a symptom of Down syndrome?

Some common physical features of Down syndrome include: A flattened face, especially the bridge of the nose. Almond-shaped eyes that slant up. A short neck.

Which of the following are characteristics of Down syndrome quizlet?

Characteristics

  • eyes that slant upward, have oblique fissures, have epicanthic skin folds on the inner corner, and have white spots on the iris.
  • low muscle tone.
  • small stature and a short neck.
  • a flat nasal bridge.
  • single, deep creases across the center of the palms.
  • a protruding tongue.

Which of the following is the most common cause of Down syndrome quizlet?

About 95 percent of the time, Down syndrome is caused by trisomy 21 — the person has three copies of chromosome 21, instead of the usual two copies, in all cells. This is caused by abnormal cell division during the development of the sperm cell or the egg cell.

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When is Down syndrome diagnosed?

The test is usually done at 15 to 22 weeks of pregnancy. Integrated screening test. Your provider combines the results from the first trimester screening and the second trimester screening to better estimate the chances that your baby may have Down syndrome.

What are the 3 types of Down syndrome?

There are three types of Down syndrome:

  • Trisomy 21. This is by far the most common type, where every cell in the body has three copies of chromosome 21 instead of two.
  • Translocation Down syndrome. In this type, each cell has part of an extra chromosome 21, or an entirely extra one. …
  • Mosaic Down syndrome.

What causes Down syndrome quizlet?

The syndrome is caused by an extra copy of Chromosome 21, and in today’s Nature paper, researchers at the University of Massachusetts Medical School describe a way to “silence” that extra chromosome, meaning it’s still there but its genes don’t get “turned on,” they don’t function and cause problems.

Which of the following is a physical manifestation of Down syndrome quizlet?

Common physical signs of Down syndrome include1,2: Decreased or poor muscle tone. Short neck, with excess skin at the back of the neck. Flattened facial profile and nose.

What is the most common cause of Down syndrome maternal nondisjunction?

Nondisjunction of chromosome 21 is the leading cause of Down syndrome. Two risk factors for maternal nondisjunction of chromosome 21 are increased maternal age and altered recombination.

What is the most common cause of Down syndrome quizlet maternal nondisjunction?

Down syndrome is caused by a random error in cell division that results in the presence of an extra copy of chromosome 21. The type of error is called nondisjunction (pronounced non-dis-JUHNGK-shuhn).

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What is the most common cause of Down syndrome a paternal nondisjunction B maternal translocations C maternal nondisjunction D paternal translocations?

Trisomy 21 is the cause of approximately 95% of observed Down syndrome, with 88% coming from nondisjunction in the maternal gamete and 8% coming from nondisjunction in the paternal gamete.