Chromosome Structure and Numbers
A Grade 12 Biology worksheet on chromosome structure, karyotypes, and numerical chromosomal abnormalities.
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Chromosome Structure and Numbers
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Read each question carefully and provide your best answer. Diagrams may be helpful for some questions.
1. Which of the following best describes the function of a telomere?
To facilitate crossing over during meiosis
To protect the ends of chromosomes from degradation
To serve as the attachment point for spindle fibers
To condense chromatin into a compact structure
2. A human karyotype typically displays:
The protein sequence of all genes
The complete set of chromosomes arranged by size and shape
The number of homologous chromosomes in a gamete
The genetic mutations present in an individual
3. The constricted region of a chromosome where sister chromatids are joined is called the .
4. A cell with an abnormal number of chromosomes is described as .
5. Down syndrome is a common example of , specifically trisomy 21.
6. Referring to the image, briefly describe the primary components of a eukaryotic chromosome during metaphase.
7. Explain the difference between autosomes and sex chromosomes in humans. How many of each are present in a normal human diploid cell?
8. All species have the same number of chromosomes.
True
False
9. Polyploidy is a condition where an organism has an extra set or sets of chromosomes.
True
False
Match the term on the left with its definition on the right.
10. Diploid
a. The process of forming gametes.
11. Haploid
b. Having two sets of chromosomes.
12. Nondisjunction
c. Having one set of chromosomes.
13. Gametogenesis
d. Failure of chromosomes to separate properly during cell division.