4. Distinguish between the following pairs
(a) Cytokinesis and Karyokinesis
(b) DNA and RNA
(c) Nucleosome and Nucleotide
(d) Centrosome and Centromere
(e) Haploid and Diploid
Answers
Answer:
Karyokinesis is the process of division of the nucleus of a cell during the phase of division (mitosis or meiosis). Cytokinesis is the process of division of cytoplasm of the cell. Cytokinesisdivides cytoplasm and organelles including nuclei into its daughter cells
Chromosomes contain tightly packed DNA molecules while in case of chromatids, the DNA molecules are unwound. A chromosome is made up of a single, double-stranded DNA molecule while a chromatid comprises of two DNA strands joining collectively by their centromere. The chromatids contain a substance called chromatin.
Explanation:
Chromosomal DNA is packaged inside microscopic nuclei with the help of histones. These are positively-charged proteins that strongly adhere to negatively-charged DNA and form complexes called nucleosomes. ... Nucleosomes fold up to form a 30-nanometer chromatin fiber, which forms loops averaging 300 nanometers in length.
Answer:
(a) Cytokinesis is the the division of the cytoplasm during the M phase of the cell cycle.
Karyokinesis is the division of the nucleus during the M phase of the cell cycle.
(b) DNA stands for Deoxyribonucleic acid.RNA stands for ribonucleic acid. DNA contains the sugar deoxyribose, while RNA contains the sugar ribose. ... DNA is a double-stranded molecule, while RNA is a single-stranded molecule. DNA is stable under alkaline conditions, while RNA is not stable. DNA and RNA perform different functions in humans
(c) Nucleosome:The nucleosome is the fundamental subunit of chromatin. Each nucleosome is composed of a little less than two turns of DNA wrapped around a set of eight proteins called histones, which are known as a histone octamer.
Nucleotide :A nucleotide is one of the structural components, or building blocks, of DNA and RNA. A nucleotide consists of a base (one of four chemicals: adenine, thymine, guanine, and cytosine) plus a molecule of sugar and one of phosphoric acid.
(d) The centromere is a part of a chromosome that links the sister chromatids or dyads. The spindle fibers attach to it during mitosis.
Centrosome is the organelle where all the cell microtubules get organized.They occur only in animal cells.
(e) Diploid cells contain two complete sets (2n) of chromosomes. Haploid cells have half the number of chromosomes (n) ....