Meiosis: specialized cell division that yields 4 nonidentical, haploid gametes in sexually reproducing diploid organisms Only occurs specialized (diploid) cells like testes & ovaries in humans to make sperm and egg Involves two rounds of division (meiosis 1 &...
Sexual Life Cycle: alteration of halving and doubling chromosome count in each generation In sexual reproduction two parents produce offspring with a unique combination of genes. In eu. results in gamete formation Increases genetic variation bcuz random mutations can...
Disruptions to cell cycle or inability to carry out apoptosis can lead to cancer Cancer Cells Cancer: unregulated/out of control cell division, results from genetic changes affecting genes whose proteins regulate the cell cycle Normal cells become cancer cells by the...
Internal Regulation of the Cell Cycle Functional Limitations Surface-to-volume ratio: when surface area is small compared to volume → cell growth stops or cell division begins Genome-to-volume ratio: ability of genome to function is limited by by finite amount of...
G2 of Interphase Prophase (condensation) Prometaphase The last part of interphase: - A nuclear envelope encloses the nucleus. - Nucleoli usually present in nucleus - Two centrosomes have formed by duplication - Each centrosomes contain two centrioles -...
Cell Cycle: is a highly regulated series of events for the growth and reproduction of eukaryotic cells Three stages: Interphase, Mitosis, & Cytokinesis Smaller cells better because easier to coordinate chromosomes and microtubules with less ATP DNA content doubles...
A change/mutation in the structure of a receptor protein or signaling molecule affects the activity of the signaling pathway and can alter the cellular response Chemicals that interfere with any component of the signaling pathway may activate or inhibit it: toxins,...
Cell undergoes programmed cell death where cell components are orderly disposed of Cell shrinks and then lysosomes’ hydrolytic proteins (proteases, amylases [carbs], nucleases, etc.) fragment DNA and organelles that are packaged vesicles digested by white blood cells...
After the ligand binds, the intracellular domain of the receptor protein changes shape, initiating transduction of the signal by converting it into a form that causes cell response Main Idea: molecules interact with each other to relay/amplify signal SECOND MESSENGERS...
Signaling Molecules: small molecules that bind to larger receptors of specific target cells Hydrophilic ligands: cannot cross membrane and bind to membrane receptors Ex: proteins that are both large and polar...
The addition of a phosphate group to one or more sites on the protein, which alters the activity of the protein Usually exchanges hydroxyl R group with phosphate Switches proteins on → increases potential energy and ability for chemical work Protein phosphorylation...