metabolic pathways consist of an ordered set of chemical reactions that are catalyzed by enzymes 1 many pathways are universal among living organisms 2 Each pathway contains multiple intermediate products and there are small molecular differences between the intermediaries 3 Each step within the pathway or the conversion from one intermediate to the next is catalyzed by an enzyme each enzyme conducts a single chemical reactions but coordination of many enzymes can produce variety of outcomes 4 Each pathway is regulated to ensure the optimal use of resources and to maintain the health of the cell if there is plenty of ATP respiration pathway which produces ATP will slow down homeostasis many metabolic processes are reversible methods of pathway regulation 1 changing amount of enzymes in pathway usually too slow enzyme levels are usually altered by controlling amount of mRNA produced from the gene that encodes enzyme 2 increasing or decreasing activity of enzyme due to binding of a small regulatory compound 6 general mechanisms can regulate rate of each step in pathway 1 Substrate availability if concentration increases rate of reaction will increase substrates must collide with enzymes to initiate binding so collisions occur most often with more concentration used as forms of drugs 2 Competitive inhibition inhibitor competes with substrate for active site and if it binds first substrate is blocked from entering and enzyme is inhibited often 3 Noncompetitive control substances bind to a site away from active site which can either enhance or inhibit enzyme s function by changing shape of active site 4 Feedback inhibition when a product inhibits an earlier step in the pathway like the enzyme that was directly involved in making that product 5 Modification of the enzyme can cause change in shape of active site which can either increase or decrease enzyme activity ex adding phosphate group 6 Changing enzyme concentrations turning genes for enzymes on and off substances that inhibit enzymes in a central pathway can have deadly effects for cell or organism ex cyanide and arsenic are inhibitors of cell respiration carb and protein 4 kcal g lipid 9 kcal g solving obesity problem medical approaches surgical options and some drugs behavior change support groups healthy cooking classes societal change building parks and bike lanes taxing snack foods and sugary sodas changing school lunches expanding P E classes somatic cells consist of all the non reproductive cells in an organism go through the process of mitosis type of cell division that results in 2 identical daughter cells meiosis type of cell division that prepares an organism for sexual reproduction germ cells found in ovaries and testes go through meiosis to produce gametes animals are sperm and egg cells differentiation certain genes found in cell s nucleus are turned on or off mitosis and meiosis are the processes by which cells divide and grow chromosomes in prokaryotic cells located in cytoplasm eukaryotic cells located in nucleus chromosomes made up of DNA and proteins genes info stored in DNA as segments called genes histone protein molecules proteins that associate with DNA in a very precise way 1 couple with DNA at regularly spaced intervals 2 help wind DNA into organized compact structure called chromosome homologue each member of a chromosome pair chromatin combo of DNA and proteins that fill eukaryotic nucleus humans have 46 chromosomes haploid cells contain only one copy of each chromosome can combine and form a diploid zygote 5 major stages of development of cell cycle 1 G1 chromosomes condense 2 synthesis S DNA is duplicated 3 G2 DNA integrity is checked and repaired 4 mitosis M chromosome sets separate equally 5 cytokinesis division of parental cell into 2 daughter cells start 1 again stages G1 S and G2 interphase which is very similar in almost every type of cell after chromosome has replicated two copies remain attached at a point called the centromere IN CLASS glucose and insulin levels mirroring each other insulin slightly under glucose levels diabetes projected to double or triple by 2050 so levels 1 in 3 adults occurs in about 8 3 of Americans hormones insulin abnormally high blood glucose frequent thirst hunger and urination fatigue weight loss blurred vision impaired cognitive function long term damage to multiple organ systems diabetes mellitus variable disorder of carb metabolism caused by a variety of factors and usually characterized by inadequate production or utilization of insulin not only about getting glucose but getting glucose in bloodstream and making sure sufficient ATP is made from that glucose after digestive process complete 20 30 min is how long you will be able to keep going healthcare cost in US 245 billion digested carbs e g glucose diffuse into blood vessels in small intestine after cleared from digestive system insulin a hormone C254 H377 N65 O76 S6 hexamer insulin chemical released by a cell or organ in one part of an organism that affects cells in other parts of the organism often active at very low concentration they move actions somewhere other than where they reside produced in beta cells in pancreas regulates many metabolic processes glycogen medium term energy storage molecule insulin stimulates removal of glucose from blood and its storage as glycogen lowering blood sugar insulin released by beta cells when high blood glucose glucagon stimulates conversion of glycogen into glucose raising blood sugar glucagon released by alpha cells when low blood glucose Type 2 diabetes 95 of humans with diabetes reduced insulin sensitivity or production exercise diet drugs affecting insulin sensitivity production insulin replacement therapy Risk factors overweight fat distribution inactivity genetics race age prior gestational diabetes Type 1 diabetes 5 humans with diabetes no insulin production at all insulin replacement theory caused by autoimmune destruction of beta cells of pancreas
View Full Document