Mitosis and Meiosis Overview

Mitosis and Meiosis

• Mitosis is a cell division process that produces two genetically identical diploid daughter cells from a single diploid parent cell
• Mitosis purposes include growth, repair, and asexual reproduction
• In mitosis, the number of chromosomes remains the same in the parent and daughter cells
• Key structures involved in mitosis include chromosomes, sister chromatids, centromeres, kinetochores, centrosomes, mitotic spindle, kinetochore microtubules, and non-kinetochore microtubules
• The cell cycle consists of interphase (G1, S, G2) and the mitotic phase (mitosis and cytokinesis) and each stage has distinct events
• Checkpoints (G1, G2, and M) regulate the cell cycle ensuring proper cell division
• Growth factors, density dependence, and anchorage dependence regulate cell cycle. Hypothetical scenarios related to these processes can be considered.
• Meiosis is a type of cell division that produces four genetically diverse haploid gametes from a single diploid parent cell
• Meiosis is crucial for sexual reproduction, resulting in genetic variation among offspring.
• Meiosis I and II involve different stages of division, resulting in changes in ploidy levels
• Important meiotic terms include homologous chromosomes, sister chromatids, non-sister chromatids, tetrads, chiasmata, and crossing over
• The phenomenon of independent assortment during meiosis contributes to genetic variability among offspring

The Immune System

• Innate immunity and adaptive immunity are two categories of immunity.
• Innate immunity blocks pathogens from entering the body and triggers rapid responses upon pathogen recognition.
• Adaptive immunity develops through a process involving major cell types and comparing primary and secondary immune responses.
• The lymphatic system plays a vital role in the immune response containing major organs and structures.
• Antigen receptors (B and T cells) are essential in adaptive immunity, and their function is determined by their specific shape.
• Pathogens, antigens, and epitopes are related and distinct.
• Antibody-antigen interactions, clonal selection, and proliferation are important in the adaptive immune responses.
• Cell-mediated and humoral responses are distinct components of adaptive immunity
• White blood cells (leukocytes) play different roles in both innate and adaptive immunity, often categorized accordingly
• Macrophages, though initially part of innate immunity, also function in adaptive immunity
• Vaccines work by stimulating a secondary adaptive immune response.

Viruses

• Viruses are distinct from cells as they lack certain cellular structures.
• Viruses possess nucleotide genomes, protein capsids, and potentially phospholipid envelopes, depending on the type of virus.
• Viruses are obligate intracellular parasites and rely on host cells for replication.
• The lytic and lysogenic cycles differ for phages, while animal viruses with envelopes exhibit a different life cycle compared to phages.
• Retroviruses have a unique replication mechanism differing from other types of viruses due to their reverse transcription and unique genome.
• Overall, viruses show considerable genetic variation in their genomes.

Overall Learning Outcomes

• The role of vaccines in human health, relationship to adaptive immunity, and the danger factors of viruses such as measles are important concepts.

This quiz explores the processes of mitosis and meiosis, detailing the stages of the cell cycle and the key structures involved. Understand the purposes of cell division, including growth, repair, and reproduction. Test your knowledge on the differences between mitosis and meiosis and the regulation of the cell cycle.