Biology MCQs
Topic Notes: Biology
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
101
Which type of cells in multicellular organisms undergo the process of mitosis?
Answer:
somatic cells
Mitosis is the process of cell division that results in two genetically identical daughter cells. In multicellular organisms, this process occurs in somatic cells, which are all the non-reproductive cells of the body, to facilitate growth, tissue repair, and asexual reproduction.
102
During the M phase of the cell cycle, into how many daughter cells does the parent cell divide via mitosis?
Answer:
two daughter cells
Mitosis is a type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus. This process is essential for growth, tissue repair, and asexual reproduction in eukaryotic organisms.
103
Which biological process serves as the fundamental mechanism for the development of a multicellular organism from a single fertilized cell?
Answer:
mitosis
Mitosis is the process of cell division that results in two genetically identical daughter cells. It is the essential mechanism for growth, tissue repair, and the development of a complex multicellular body from a single-celled zygote, ensuring that every cell contains the same genetic information.
104
What is the term for a form of reproduction where a single parent produces genetically identical offspring through simple cell division?
Answer:
asexual reproduction
Asexual reproduction involves a single parent organism producing offspring without the fusion of gametes. This process relies on mitotic cell division, resulting in progeny that are genetically identical clones of the parent organism.
105
During cell division, chromatin condenses into which highly ordered structures?
Answer:
chromosomes
Chromatin consists of DNA and proteins that exist in a loose, thread-like state during interphase. As a cell prepares for division, this chromatin undergoes significant condensation and coiling to form distinct, compact structures known as chromosomes, which facilitate the equal segregation of genetic material into daughter cells.
106
Which type of cell is characterized by the formation of a cell plate during cytokinesis?
Answer:
plant cells
During plant cell division, the rigid cell wall prevents the cell from pinching inward. Instead, vesicles derived from the Golgi apparatus align at the equator of the cell to form a cell plate, which eventually develops into the new cell wall separating the two daughter cells.
107
What is the initial observable indicator of cytokinesis in animal cells?
Answer:
cytokinesis
The formation of a cleavage furrow is the first visible sign of cytokinesis in animal cells. This process involves the contraction of an actin-myosin ring at the cell equator, which pinches the plasma membrane inward, eventually dividing the cytoplasm into two distinct daughter cells.
108
By what mechanism does the nucleus divide during binary fission in unicellular eukaryotes?
Answer:
mitosis
In unicellular eukaryotes, binary fission involves the replication of the genetic material followed by the division of the nucleus through mitosis. This ensures that each daughter cell receives an identical set of chromosomes, maintaining genetic continuity between the parent and the offspring.