Free Chromosomes MCQs with Answers
633 Chromosomes MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Chromosomes are DNA-protein structures that carry genes and become visible during cell division. Coverage includes chromatin, centromeres, sister chromatids, homologous chromosomes, chromosome number, and the distinction between diploid and haploid cells, with links to DNA replication, mitosis and meiosis.
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- A. 23
- B. 44
- C. 46
- D. 92
Explanation: Human body cells are diploid with 46 chromosomes, which is 23 homologous pairs made up of 22 pairs of autosomes and one pair of sex…
Correct answer: 46- A. telomere
- B. centromere
- C. centriole
- D. chromomere
Explanation: The centromere holds sister chromatids together and carries the kinetochore, the protein structure the spindle microtubules attach to…
Correct answer: centromere- A. histones
- B. collagens
- C. tubulins
- D. keratins
Explanation: Histones are small positively charged proteins that bind the negatively charged phosphate backbone of DNA, forming nucleosomes that…
Correct answer: histones- A. the complete set of genes in a gamete
- B. the sequence of bases in one chromosome
- C. a display of all the chromosomes of a cell arranged in pairs by size and shape
- D. the number of chromatids in a chromosome
Explanation: Chromosomes are photographed at metaphase, when they are most condensed, then cut out and arranged in numbered pairs, which makes an…
Correct answer: a display of all the chromosomes of a cell arranged in pairs by size and shape- A. 22
- B. 23
- C. 21
- D. 44
Explanation: Twenty two pairs are autosomes, which carry the genes for body characters and are identical in appearance in both sexes, and the remaining…
Correct answer: 22- A. Nucleus
- B. Mitochondria
- C. Chloroplast
- D. Ribosome
Explanation: Mitochondria are called the powerhouse because they produce ATP through oxidative phosphorylation.
Correct answer: Mitochondria- A. To protect the ends of chromosomes
- B. To hold sister chromatids together
- C. To carry genetic information
- D. To initiate DNA replication
Explanation: The centromere joins the two sister chromatids and carries the kinetochore, the protein plate that the spindle microtubules attach to…
Correct answer: To hold sister chromatids together- A. Two identical double helical DNA molecules
- B. Two different double helical DNA molecules
- C. A double helical DNA molecule distributed in both chromatids
- D. Histone chains wrapped around DNA core
Explanation: Replication is semi conservative and highly accurate, so the two sister chromatids each hold a complete double helix and the two are…
Correct answer: Two identical double helical DNA molecules- A. Energy production and storage
- B. Protein synthesis and regulation
- C. Storage of genetic information
- D. Lipid metabolism and transport
Explanation: A chromosome is DNA packaged with histones, and its role is to hold the hereditary information and pass it on accurately when the cell…
Correct answer: Storage of genetic information- A. Hormones
- B. Elastin
- C. Histone
- D. Nucleosome
Explanation: Histones are small positively charged proteins that the negatively charged DNA winds around, condensing roughly two metres of DNA into a…
Correct answer: Histone- A. 23
- B. 46
- C. 0
- D. None of These
Explanation: Tetrads form in prophase I of meiosis when homologous chromosomes pair and undergo crossing over.
Correct answer: 0- A. Identified barr bodies
- B. Detected sex linkage
- C. Pointed out mutational changes
- D. Gave the number of human chromosomes
Explanation: Tjio and Levan established in 1956 that the normal human diploid chromosome number is 46, correcting the earlier accepted count of 48.
Correct answer: Gave the number of human chromosomes- A. Structural of gene
- B. Functional unit of RNA
- C. Functional unit gene
- D. Replication unit of gene
Explanation: A cistron is the functional unit of a gene, specifically a DNA segment that codes for one polypeptide or functional RNA product.
Correct answer: Functional unit gene- A. Bands
- B. Loops
- C. Both bands and loops
- D. All of the above
Explanation: Balbiani's giant polytene chromosomes in Chironomus larvae show a characteristic pattern of dark transverse bands and expanded regions or…
Correct answer: Both bands and loops- A. 10
- B. 12
- C. 06
- D. 09
Explanation: In the traditional solenoid model of the 30 nm chromatin fibre, six nucleosomes are arranged in one helical turn.
Correct answer: 06- A. One half of chromosome
- B. Haploid chromosome
- C. Complete chromosome
- D. Duplicate chromosome
Explanation: After DNA replication, a chromosome consists of two identical sister chromatids joined at the centromere, so one chromatid forms one half…
Correct answer: One half of chromosome- A. Lampbrush chromosome
- B. Hetero chromosome
- C. Supernumerary chromosome
- D. Polytene chromosome
Explanation: A polytene chromosome is a giant chromosome formed by repeated DNA replication without cell division, producing many aligned chromonemata…
Correct answer: Polytene chromosome- A. Acrocentric
- B. Telocentric
- C. Submetacentric
- D. Acentric
Explanation: The human Y chromosome is generally classified as acrocentric because its centromere lies close to one end, producing one very short arm…
Correct answer: Acrocentric- A. Telocentric
- B. Submetacentric
- C. Acrocentric
- D. Acentric
Explanation: The human X chromosome is classified as submetacentric because its centromere is slightly away from the middle, giving arms of unequal…
Correct answer: Submetacentric- A. Heterosomes
- B. Replosomes
- C. Androsomes
- D. Autosomes
Explanation: Autosomes are homologous chromosome pairs found in both males and females and are not the sex chromosomes.
Correct answer: AutosomesChromosomes MCQs: common questions
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There are 633 Chromosomes MCQs in the Biology bank, shown 20 to a page with the correct answer and an explanation on each.
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Yes. Each Chromosomes question shows the correct option and a written explanation of why it is correct, so a wrong answer teaches you something rather than just being marked wrong.
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