Unit-1: Cell Theory and Kingdoms of Life Flashcards
What are the two main types of cells?
Prokaryotic and Eukaryotic cells
Who proposed the five-kingdom classification system?
Robert Whittaker
What are the five kingdoms in the biological classification system?
Monera, Protista, Fungi, Plantae, and Animalia.
What phases make up the cell cycle?
G1 phase, S phase, G2 phase, and M phase (mitosis).
What is the process of cell division in eukaryotic cells called?
Mitosis
What is the significance of the S phase in the cell cycle?
It is the phase where DNA synthesis occurs, resulting in the duplication of chromosomes.
Q: What is meiosis?
A: A type of cell division that reduces the chromosome number by half, resulting in haploid gametes.
Q: What occurs during prophase I of meiosis?
A: Homologous chromosomes pair up and exchange genetic material through crossing over.
Q: What is the role of microtubules during mitosis?
A: They help in the movement and separation of chromosomes to ensure accurate distribution to daughter cells.
Q: How does meiosis contribute to genetic diversity?
A: Through processes like crossing over and the independent assortment of chromosomes during meiosis I.
Q: What can result from disruptions in the cell cycle?
A: Uncontrolled cell division, which can lead to cancer.
Q: What are biological macromolecules, and why are they important?
A: They are large molecules essential for life, playing key roles in cellular functions and processes.
Q: What is the difference between haploid and diploid cells?
A: Haploid cells contain one set of chromosomes (n), while diploid cells contain two sets (2n).
Q: What is the function of the Golgi apparatus in eukaryotic cells?
A: It is involved in the modification, sorting, and packaging of proteins and lipids for secretion or delivery to other organelles.
Q: What is the significance of the cell theory?
A: It states that all living organisms are composed of cells, and cells are the basic unit of life.
Q: What is the primary difference between prokaryotic and eukaryotic cells?
A: Prokaryotic cells lack a true nucleus and membrane-bound organelles, while eukaryotic cells have a defined nucleus and complex structures.
Q: What is the role of sister chromatids during cell division?
A: Sister chromatids are identical copies of a chromosome that are separated during mitosis and meiosis to ensure each daughter cell receives the correct genetic material.
Q: How does crossing over contribute to genetic diversity?
A: Crossing over allows homologous chromosomes to exchange genetic material during prophase I of meiosis, leading to new combinations of alleles in gametes.
Q: What are gametes, and how are they formed?
A: Gametes are haploid cells (sperm and egg) formed through meiosis, which reduces the chromosome number by half.
Q: What is the significance of chiasmata during meiosis?
A: Chiasmata are points where homologous chromosomes exchange genetic material, facilitating genetic variation in the resulting gametes.
Q: What are the five kingdoms of living organisms?
A: The five kingdoms are Monera, Protista, Fungi, Plantae, and Animalia, each classified based on their characteristics and evolutionary relationships.
Q: How does the cell cycle ensure proper cell division?
A: The cell cycle includes checkpoints that regulate the progression through phases like G1, S, G2, and M, ensuring accurate duplication and distribution of chromosomes.
Q: What is the role of microtubules in mitosis?
A: Microtubules form the spindle apparatus that helps align and separate chromosomes during mitosis, ensuring each daughter cell receives the correct number of chromosomes.
Q: What is the origin of cancer related to the cell cycle?
A: Cancer can arise from mutations that disrupt the regulation of the cell cycle, leading to uncontrolled cell division and the formation of tumors.
Q: Who proposed the classification of living organisms into five kingdoms?
A: Robert Whittaker proposed this classification system, which distinguishes organisms based on their cellular structure and nutritional modes.
Q: What is the difference between haploid and diploid cells?
A: Haploid cells contain one set of chromosomes (n), while diploid cells contain two sets (2n), which is typical for somatic cells in eukaryotes.
Q: What are biological macromolecules, and what roles do they play in cells?
A: Biological macromolecules, such as proteins, nucleic acids, carbohydrates, and lipids, are essential for various cellular functions, including structure, energy storage, and genetic information.
Q: What is the process of mitosis, and why is it important?
A: Mitosis is the process of cell division that results in two genetically identical daughter cells, crucial for growth, repair, and asexual reproduction in organisms.
Q: How do Archaea differ from Bacteria?
A: Archaea are a distinct group of prokaryotic organisms that often thrive in extreme environments and have unique biochemical and genetic characteristics compared to Bacteria.
Q: What is the significance of the cell theory in biology?
A: The cell theory states that all living organisms are composed of cells, which are the basic units of life, emphasizing the importance of cells in the study of biology.
