Gen Bio Definitions and Notes Answered PDF

Gen Bio Definitions and Notes Answered Lesson 1: Biomolecules ❖ Level of Biological Organization Atoms Molecules Macromolecules (Proteins) Cell Organelles (parts of the cell) ❖ Carbohydrates Short-term energy storage Found...

Gen Bio Definitions and Notes Answered Lesson 1: Biomolecules ❖ Level of Biological Organization Atoms Molecules Macromolecules (Proteins) Cell Organelles (parts of the cell) ❖ Carbohydrates Short-term energy storage Found in plants Monosaccharides - subunit of sugar Glycosidic bond ❖ Sugars Glucose - bread Fructose - fruits Galactose - dairy Raffinose - beans, cabbages, and whole grains Starch - wheat,rice,potatoes ❖ Lipids Fatty acids - subunit of Lipids Ester bond Amphiphilic Polar head - hydrophilic Nonpolar tails - hydrophobic Nonaponifiable Lipids - cannot be disintegrated through hydrolysis  Saponifiable Lipids - can undergo hydrolysis Nonpolar lipids (triglycerides) - fuel/energy storage Polar lipids - used in membranes Simple Lipids - esters of fatty acids with alcohols Fats Waxes Complex lipids Phospholipids - nitrogen-containing bases Glycolipids - contains fatty acid, sphingosine, and carbs Sterols - head contains planar steroid ring (cholesterol) Other complex lipids - amino lipids Fatty Acids - carboxylic acids Saturated - lack of carbon double bonds (butter) higher melting point Unsaturated - more than one double bond (margarine as trans-fat) ❖ Nucleic Acids Nucleotides - subunit Phosphodiester and Hydrogen bond Transfer genetic information Protein synthesizer ❖ Proteins Amino acid - subunit of proteins Peptide bond Structural - make-up the physical body of an organism Functional (enzymes) - what cell uses to build things Types of Protein Structures Primary - amino acid sequence Secondary - helix  Tertiary - coiling of polypeptide Quaternary - two or more polypeptide Lesson 2: Photosynthesis ❖ Law of thermodynamics Zeroeth law - two systems in equilibrium with a third system are in thermal equilibrium First law - conservation of energy (cannot be created nor destroyed) Second law - entropy of isolated system always increases Third law - entropy approaches constant as temperature approaches zero ❖ ❖ Energy Currency ATP Adenosine Triphosphate Supplies energy for cellular functions.  Energy is released when a phosphate group is removed. ADP Adenosine Diphosphate The “spent” form of ATP. Converts back to ATP when a phosphate group is added (recharging process) ❖ Energy in Biomolecules Carbohydrates: 1 glucose molecule yields up to 36 ATP. Fats/Lipids: 1 triglyceride yields up to 146 ATP. Proteins: Yields 36 ATP but are not a primary energy source. ❖ Coupled Reactions: organic reaction involving 2 chemical species joined with help of metal catalyst ❖ Photosynthesis: Converts light energy into chemical energy. Inputs CO2 (from stomata), H2O (from roots), and light energy. Chlorophyll a and Chlorophyll b absorb red and blue light; green light is reflected. ❖ Light Reactions (in Thylakoid) Photophosphorylation: ATP synthesis powered by light through chemiosmotic mechanism Electrons flow through the Z-scheme, converting light (then electrical) to chemical energy (as reduced NADPH and ATP). Chloroplasts - the site of photosynthesis Chlorophyll a – main photosynthetic pigment Chlorophyll b – accessory pigment When pigment absorbs light, it goes from a ground state into an excited state (unstable) ❖ Dark Reactions (Calvin Cycle in Stroma)  Light-independent reaction; uses ATP and NADPH. Fixes carbon into sugar molecules. ❖ ATP Synthase: Occur in Mitochondria Enzyme that synthesizes ATP from ADP and inorganic phosphate. ATPase: Removes phosphate groups. ATP Synthetase: addition of phosphate\ ❖ Proton Motive Force Movement of protons and electrons in the mitochondrial membrane generates ATP through movement Uses respiratory chain complexes for efficient ATP production. Lesson 3: Respiration ❖ Cellular Respiration Converts chemical energy (food) into ATP. Involves oxygen consumption and CO2 release. ❖ Coenzymes in Respiration NAD+: Energy carrier; becomes NADH after picking up electrons and H+. FAD+: Becomes FADH2 after reduction. ❖ Processes Glycolysis: Occurs in the cytoplasm. Anaerobic (no oxygen required). Yields 2 ATP, 2 NADH, and 2 pyruvates. ❖ Krebs Cycle (Citric Acid Cycle): Occurs in the mitochondrial matrix.  Aerobic process. Produces 6 NADH, 2 FADH2, 4 CO2, and 2 ATP per glucose molecule. ❖ Electron Transport Chain (ETC): Occurs in the inner mitochondrial membrane. Produces 34 ATP and H2O. ❖ Fermentation: Occurs when oxygen is unavailable. Produces 2 ATP per glucose molecule. Types: Lactic Acid Fermentation: In muscles; causes fatigue. Alcoholic Fermentation: In yeast; produces ethanol. Lesson 4: Reproduction ❖ Asexual Reproduction: Involves one parent; offspring are genetically identical (clones). Examples: Fission (e.g., Paramecium) - division into equal parts Fragmentation and regeneration (e.g., starfish) - two or more parts capable of becoming individual Budding (e.g., Hydra) - outgrowth from its parent and then detaches itself Sporulation (e.g., Rhizopus fungi)- aggregation of cells surrounded by spore ❖ Sexual Reproduction: Involves two parents; offspring have genetic variation. Types of gamete union: Isogamy: Fusion of similar gametes (e.g., Chlamydomonas).  Heterogamy/Oogamy: Fusion of dissimilar gametes, e.g., egg and sperm (e.g., humans). ❖ Special Terms Hermaphrodite Both male and female reproductive tissues Bisexual reproduction - union of gametes from genetically diff parents Parthenogenesis - development of unfertilized gamete ❖ ❖ ❖ Stages of Development: Gametogenesis: Formation of gametes (haploid cells). [terminated by death] Fertilization: Formation of a diploid zygote. Cleavage: Mitotic divisions form a blastula.  Gastrulation: Formation of germ layers (ectoderm, mesoderm, endoderm). Totiponent cell - a cell that can differentiate to become any kind of cell Organogenesis: Development of organ systems. ❖ Human Reproductive Systems: Male: Includes testis (sperm production), epididymis (storage), vas deferens (transport), scrotum - supports and temperature regulator Urethra - urinary bladder Seminal vesicle - secretes fluid that forms part of the semen Prostate gland - secretes fluid that provide alkalinity Cowper’s gland - paired glands Female: Includes ovaries (egg production), fallopian tubes (fertilization site), uterus (embryo development), and vagina (entryway). Ovaries - release oocytes Endometrial lining - embryo implants and develop ❖ Menstrual Cycle Ovarian Cycle Follicular Phase: Follicles mature, estrogen thickens the uterine lining. Ovulation: The release of a mature oocyte from the ovary. Luteal Phase: TCorpus luteum secretes progesterone to prepare the uterus to gestation Uterine Cycle  Secretory Phase: Corresponds to the luteal phase of the ovaries. The endometrium undergoes final changes before it can receive the embryo during implantation. Menstrual Phase: Occurs during days 1-5 of the cycle Proliferative Phase: Occurs during days 8-14, The endometrium heals and thickens due to estrogen secretion. ❖ Stages of Development Fertilization: Occurs in the fallopian tube, resulting in the formation of a unicellular zygote. Cleavage: Takes place in the fallopian tube after fertilization, where the zygote begins to divide. Morula and Blastocyst: Morula: A mass of 16-32 cells. Blastula: A stage with over 60 cells. Blastocyst: Composed of an inner cell mass (which becomes the embryo) and the trophoectoderm (which forms the placenta). ❖ Implantation: The blastocyst implants itself in the endometrium, signaling the start of pregnancy. ❖ Gestation: Refers to the carrying of the embryo in the female reproductive tract, specifically the uterus, which lasts up to 9 months. Human Embryo: The first two months of gestation. Human Fetus: The period from months 3-9 of gestation. ❖ Differentiation and Growth Growth: A stage of development characterized by an increase in the size of an individual. Monozygotic Twins: Identical twins that result from the splitting of a single zygote during the first cleavage stage.  Dizygotic Twins: Fraternal twins that result from the fertilization of two separate eggs, developing almost simultaneously. ❖ Types of Contraception ❖ Parts of a Flower Sepals: The outermost whorl of the flower; collectively called the calyx. Petals: Located inside the sepals, may be brightly colored; collectively called the corolla.  Stamen: The male reproductive structure of the flower, which produces microspores (pollen). Anther: Part of the stamen that contains the microsporangia (where pollen grains develop). Filament: The stalk of the anther. Pistil or Carpel: The innermost whorl of the flower, the female reproductive structure. Stigma: The part where the pollen grain attaches during pollination. Style: The stalk that connects the stigma to the ovary. Ovary: Contains one or more ovules; later becomes the fruit. Ovule: Contains the female sporangium and eventually becomes the seed. Types of Flowers Based on Reproductive Whorls Complete Flower: A flower with sepals, petals, stamens, and carpels. Incomplete Flower: A flower that lacks one or more of these whorls. Monoecious Plant: A plant with both male (staminate) and female (carpellate) flowers on the same individual. Dioecious Plant: A plant with either male or female flowers, but not both, on the same individual. Perfect/Bisexual Flower: A flower that has both stamens and carpels. Imperfect/Unisexual Flower: A flower with either only stamens (staminate) or only carpels (carpellate). Life Cycles of Plants Gametophyte: Haploid stage that produces gametes. Sporophyte: Diploid stage that produces spores called sporangia Haplontic Life Cycle The dominant stage is the haploid (gametophyte), and the only diploid stage is the fertilized egg cell. An example is the green alga Chara. Haplodiplontic Life Cycle  Includes both multicellular diploid (sporophyte) and haploid (gametophyte) generations. Moss is an example. Diplontic Life Cycle Found in flowering plants and most animals, where the organism is diploid throughout most of its life cycle, except for the gametes. ❖ Development in Flowering Plants Gametogenesis: Formation of male and female gametes. Pollination: Pollen reaches the stigma. Double Fertilization: One sperm fertilizes the egg; another forms the endosperm. Embryo Development: The zygote forms the embryo, which is nourished by the endosperm. Seed Germination: Seeds absorb water and start to grow. Mature Plant: Seedling grows into a mature plant.