Cell Division Quiz: Cytokinesis In Plants & Animals

Cytokinesis refers to the division of the cytoplasm during cell division. In animal cells, cytokinesis occurs through cleavage, where a contractile ring made of actin and myosin filaments forms around the equator of the cell. The ring contracts, pinching the cell membrane inward until it completely separates into two daughter cells. In contrast, plant cells undergo cytokinesis through the formation of a cell plate, which eventually develops into a new cell wall between the two daughter cells. Therefore, the correct answer is animal cells.

Chromatids are the correct answer because they are the two identical halves of a replicated chromosome that are held together by a centromere. During cell division, each chromatid separates and becomes an individual chromosome in the daughter cells. Therefore, chromatids are the chromosomes that are made of identical halves.

Sperms develop via meiotic division, which is a type of cell division that involves two rounds of division. In the first round, called meiosis I, the cell undergoes DNA replication and then divides into two daughter cells with half the number of chromosomes. In the second round, called meiosis II, each of the daughter cells divides again to produce four haploid cells, which eventually develop into sperms. Meiotic division is necessary for sexual reproduction as it ensures genetic diversity by producing gametes with different combinations of genetic material.

The term "kinesis" in the word cytokinesis refers to movement. Cytokinesis is the process of cell division, specifically the division of the cytoplasm. During this process, the cytoplasm of the parent cell divides into two daughter cells. The term "kinesis" indicates that this division involves movement, as the cytoplasm actively moves and separates into two distinct parts.

Higher plant cells show cell plate cytokinesis. In higher plants, cytokinesis occurs through the formation of a cell plate, which is a structure that forms in the middle of the dividing cell. This cell plate gradually expands outwards, separating the two daughter cells. This process is different from animal cells, where cytokinesis occurs through the formation of a cleavage furrow. Lower plant cells may also undergo cell plate cytokinesis, but it is not specified in the given options. Therefore, the correct answer is higher plant cells.

Cytokinesis is a part of the M-phase of cell division. The M-phase, also known as the mitotic phase, includes both mitosis and cytokinesis. Mitosis is the process of dividing the genetic material of a cell into two identical daughter cells, while cytokinesis is the physical separation of the cytoplasm and other cellular components into two distinct cells. Therefore, the correct answer is M - Phase.

During plant cell division, cell plates are formed when vesicles fuse together. Vesicles are small membrane-bound sacs that contain materials needed for cell division. These vesicles carry cell wall components to the middle of the dividing cell. As the vesicles fuse together, they create a structure called the cell plate, which eventually develops into the new cell wall that separates the two daughter cells. This process allows for the formation of a complete cell wall and the successful completion of plant cell division.

The phragmoplast in plant cell division is formed by the middle part of the spindle in the plant cells. The spindle is a structure made up of microtubules that helps in separating the chromosomes during cell division. The phragmoplast is formed towards the end of cell division and is responsible for the formation of the cell plate, which eventually develops into the cell wall. Therefore, the middle part of the spindle plays a crucial role in the formation of the phragmoplast in plant cell division.

In eukaryotic cells, protein synthesis begins with transcription, where the DNA sequence is copied into mRNA. After transcription, the mRNA undergoes RNA processing, which includes the removal of introns and the addition of a 5' cap and a poly-A tail. Finally, translation occurs, where the mRNA is used as a template to synthesize a protein. Therefore, the correct sequence of events in protein synthesis in eukaryotic cells is transcription, RNA processing, and then translation.

Microfilaments play an active role in animal meiosis. During meiosis, microfilaments are involved in various processes such as chromosome movement, spindle formation, and cytokinesis. They help in the separation of homologous chromosomes during meiosis I and sister chromatids during meiosis II, ensuring the formation of haploid gametes. Microfilaments also aid in the formation of the contractile ring during cytokinesis, which leads to the division of the cytoplasm and the formation of two daughter cells. Therefore, microfilaments are essential for the successful completion of animal meiosis.