Lsci Notes (Faye Tsang) 2 PDF

Lecture 9  Lecture 10 ReproductionI rapid cell division after fertilization Clearage > - /little gene expression & protein synthesis...

Lecture 9  Lecture 10 ReproductionI rapid cell division after fertilization Clearage > - /little gene expression & protein synthesis ball ofcells no hollow Sex differentiation- internal genitalia Gastrulation If ↑- boy > Gonadal medulla - Wolffian duct > - testis deferens * stula 7 Three-layered embryo >as - Millerian duct > regresses - Ectoderm mesoderm & dodee , If girl - > Gonadal cortex > - ovary outen layer Millerian duct > - oriduct Wolffian duit regresses Sex determination& differentiation Leydig cell > - testosterone SRY protein > - H-Y entigen > - testis formation - - SRT gene Sertoni cell > AMH(anti-millerian hormone) - - Lex-determining RegionY * FSH &4*  external - genitalia Genital tubercle Girl ↓ Boy shala Genital tubercle E glanspenis clitoris Urethafold scrotum " labia Labioscrotal scrolling major bipotentiethralgroe weeks shaft  **E to birth ( Human spermatogenesis Oogenesis (prior Spermatogonium D & ⑭ Orgonium ↓ replicate Startfrom ↓ replicate ↓ puberty primary Voyte @x2 before &x Primaryspermatoryte ↓ birth Secondaysperutoyte 2n o of of time fertilization If no , Then- stopi r i # polan body Mature oocyte FSH : Stimulates follicle development the in * orany CH = Stimulate Ovulation to happen Site of secretion Pituitary gland Target Ovary : : organ stimulated by developing follicle yellow body(Corpus Intern Estradio ploestrogen) - , * the endometrium -A thickening Progesterone - stimulated by corpus Interm. level very low Menstruation : (no fertilization , corpus Interm degenerate, less estradio/ progesterone) Trophoblast > - part of placenta. Oxytocin + Prostaglandins => stimulate contraction of uterus  Lecture 7 Cell communication I # Extracellular fluid ] high + [Na A ⑭ Grat binding of Nat > - Phosphorylation by ATP ③ Change in Protein shape > - lower its affinity for Nat ① higher affinity > - K+ - > kind # phosphate group > - release of ⑤ Return to origKt inal shape, > - affinity for lower , release * Cycle continue , [Nat-kt ATPase] - out 3 Nat 2K+ - pumps , pumps in - against the electrochemical gradient  Generation of Action Potentials Resting potential > - both k+ & Not channels (voltagegated)closed Action potentialgenerated -> Nat channels open > - flow into the well Rising phase > - threshold is crossed > membrane - potential +x Falling phase- > Nat inactivated , +open , + flows out Undershoot > - permeability fokt is higher than westing , channel closed voltage-gated it Physical signal - light , mechanical pressure , temperature Chemical signal - used in cell-cell communication neurotransmitters hormones - e g.. prostaglandis , ,  of Types signal Local Signaling > - direct contact canimal cells) Ocell junctions E [ animal cells plant cells ② cell-cell communication protein binds to another P protein 88 ⑮D & 8 E ligand-receptor binding Local regulators > very close short distances > diffusion - - , ① for long distance # ter (secrete targetcell near) y ne erohormone eastream cell same starget & secrete  Classes of hormone = three types Polypeptides 1) , ames-> water-soluble (polar 2) Steroid , other large > - lipid-soluble (non-polar) - Q ① exocytosis diffuse across cell membrane kinds to transport protein ⑪ ~ ③ ~ diffuse through the membrane 8/ cell-surface receptors kinds to receptors inthe ~ nucleus of targetcells/ receptors in cytoplasm  Lecture 8 Cell communication II Three stages - cell signalling Transduction Reception - > > - Response ↑ ↑ ↑ ③a molecules specifircese are target ell detects Binding of signaling A molecules leads to alternation of receptor ① a signaling & + that bird to the Initiate receptor. a signal transduction pathway lusually multi-step H This process is highly specific molecules (between signaling (ligand) & receptor Three types of membrane receptors