Down Syndrome,or Trisomy 21,in Humans Is Caused by an Extra

question 45

Essay

Down syndrome,or trisomy 21,in humans is caused by an extra copy of the relatively small,acrocentric chromosome #21.Including only chromosome #21,the X chromosome (medium in size and somewhat metacentric),and the Y chromosome (small and acrocentric),draw one possible array of chromosomes in the four sperm cells produced by the complete meiosis of one primary spermatocyte.For the purposes of this question,assume that males with Down syndrome produce normal ratios of sperm cells.(More than one answer is possible.)

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Definitions:

Lighter

A portable device used to generate a flame for the purpose of lighting something, such as a cigarette or candle.

Darker

Having very little light, not bright, or closer to black in color.

Gestalt Grouping

principles that describe how humans naturally organize visual elements into groups or unified wholes.

Rows

Linear arrangements of objects or data, often found in tables, lists, or seating arrangements.