Explain the structure and function of the cell nucleus. Include the terms nuclear envelope, nucleoli, chromatin,
chromosomes, autosomes, and sex chromosomes. What will be an ideal response?
ANSWER: The largest organelle is the nucleus. It is enclosed by a double membrane called the nuclear
envelope. Within the nucleus, dense regions known as nucleoli synthesize ribosomes. Dark
strands of chromatin are seen throughout the nucleus. As a cell prepares to divide, the chromatin condenses to form the chromosomes. In humans, there are 23 pairs of
chromosomes (46 chromosomes) in most cells Certain cells, such as sperm and eggs, carry
only one copy of each chromosome and have 23 unpaired chromosomes. Human males have
one pair of chromosomes that are not completely matched. Members of this pair are known
as sex chromosomes. There are two types of human sex chromosomes: X and Y. Males carry
an X chromosome and a Y chromosome, and females carry two X chromosomes. All other
chromosomes are known as autosomes.
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What will be an ideal response?
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