BIOL 1104 1st EditionExam # 4 Study Guide LecturesEndocrine- Job-maintain ECF (extracellular fluid, ISF-interstitial fluid)-homeostasis- Plasma+cells=blood- Hormone-molecule that is carried by the blood to a target to cause an effecto Target-effector that has a receptor to a specific hormoneo 2 kinds Protein-water soluble, receptor on cell surface Steroid-fat soluble, intracellular receptor (diffuses through membrane)- Germ layers-controlled differentlyo Ectoderm-nervous and dermal tissueo Endoderm-secretory/neuroendocrine- Glands o Nervous-hypothalamus, posterior pituitary, adrenal medullao Endocrine-thyroid, anterior pituitary, parathyroid, adrenal cortex, pancreas, ovary/testes- Pituitaryo Posterior-neural-cell bodies of neurons that are in the hypothalamus produce hormones. They project into the post. pituitary. They release hormones directly into the blood here.o Anterior-endocrine-neurons in the hypothalamus release tropic hormones into a capillary system at the blood brain barrier. They turn into arteries and then back into capillaries at the anterior pituitary. This is called a portal system. These hormones cause the release of different hormones into the capillaries which thengo to their targets.- Composite glands: glands that have both neural and endocrine componentso Examples: adrenals and pituitary- Hormoneso Aldosterone-regulate K/Na o Cortisol-regulate sugar- Posterior pituitary hormoneso AVP=ADH=antidiuretic hormone: target kidney, reduce urine production by retaining water. Increase in blood osmolality causes release of ito OXY=oxytocin: smooth muscle contraction of mammary glands and uterus- Anterior pituitary hormoneso Hypothalamus->ant.pit->target->negative feedbacko GHRH (growth hormone releasing hormone)-> GH (growth hormone)->liver ->IGF1o TRH (thyroid releasing hormone)->TSH (thyroid stimulating hormone)->thyroid ->thermogenesis and thyroxine (TH) (needs iodine)o GnRH (gonadotropin releasing hormone)->LH/FSH->ovary/testes ->estrogen/testosteroneo CRH (corticotropin releasing hormone)->ACTH (adrenocorticotropin releasing hormone)->adrenal cortex->cortisolo PRH (prolactin releasing hormone)->Prolactin->breast->milk letdown- Organso Adrenals Epinephrine and norepinephrine has various targets- Fight/flight, positive feedback, direct nerve innervation Cortisol has various targets- Increase glucose and decrease inflammationo Pancreas Insulin targets liver and muscle- Decrease blood sugar by uptake and turns into glycogen Glucagon targets liver and fat cells- Increase blood sugar by release, breakdown of glycogeno Parathyroid target bone and kidney Parathyroid hormone increases blood calcium- Needed for muscle contraction, nerves, and nerves Calcitonin decreases blood calcium (rare)o Sex organs Androgens released from testes to various targets Estrogen and progesterone from ovaries to various targetsNervous system- Excitability-develop and propagate action potentials (nerves and muscles)- Terms o Voltage (V)-potential energyo Potential (mV)-voltage difference between two points o Current (I)-movement of chargeo Resistance (R)-stop charge movemento Insulator-increases resistance (lipids like myelin)o Conductor-decrease resistance (water, ions)- Resting membrane potential-voltage difference across the membrane o Due to potassium (leaky K channels)o Inside is more negative than outsideo K is more concentrated inside and Na is more concentrated outsideo -70mV- Na/K pumpo Pumps ions against their concentration to reestablish resting membrane potential (Na out and K in)- Action potentialo -70mV: All gates closed except leaky K channelso -50mV: threshold: Na gates open Positive feedback causes more Na channels to openo ~40mV: Na gates close and K gates open Positive feedback causes more K gates to open Absolute refractory period-action potentials can’t fireo -90mV: K channels are slow to close so hyperpolarizing occurso -70mV: Na/K pump has restored RMP- Parts of neuronso Dendrites receive information, cell body, axon, axon terminals, synaptic clefo Neurons make up 10% of brain. Glial cells (support cells) are the rest.o Nodes of ranvier: gaps in myelin along neurons Salutatory conduction-electricity jumps nodeso Speed due to diameter of neurons and degree of myelination Multiple sclerosis is due to a degeneration of myelin which causes misfiring of neuronso Afferent-to CNS, efferent-to effector, interneurons- Graded potentialso These occur only in the dendrites. o Amplitude modulated-amount of ion flowing in determines amount of charge buildup (determined by amount of neurotransmitter (NT))o Yields frequency of action potentialso high amplitude makes high frequency makes high NT volume- Two divisions of nervous systemo Somatic-conscious, acetylcholine, skeletal muscle, excitatory, dual innervationo Autonomic-subconscious, NE and Ach, smooth muscle, cardiac muscle, glands, reciprocal innervation Sympathetic-epinephrine and norepinephrine Parasympathetic-acetylcholineMuscles- Termso Ligament-attaches bone to boneo Tendon-attaches muscle to bone- Striated-due to sarcomereso Sarcomere-functional unit of the motor systemo Thin (actin) and thick (myosin) filaments- Somatic nervous system, acetylcholine- Myelinated- Neuromuscular junction: where nerves meet muscles- Motor unit: 1 motor neuron and all its innervated fiberso Large unit-lots of fibers-no fine movement but big force (thigh)o Small unit-few fibers-fine movement but small force (fingers)- Action potentialso Acetylcholine receptors at motor end plateo Na comes in which causes a Ca influx which causes contractiono Ach is inactivated at the synapse- Contractiono Sliding filament theory Sarcomere shortens, not the individual fibers thus causing the muscle to shorten and generate force Calcium allows actin to interact with myosin. ATP activates myosin. This causes contraction. ATP is also needed to relax the muscle.o Sarcoplasmic reticulum Stores Ca in the muscle cells ATP is needed to get Ca back into ito 1 action potential yields a long increase in Ca=twitcho Sustained contraction is called tetany. Calcium stays high.o Isotonic-force is greater than the loado Isometric-load is great than the forceo Muscle fatigue happens when there is no ATP so the muscle can’t relax which causes a cramp.Cardiovascular- Arteries maintain pressure during heart relax due to arterial elastic recoil.- Arterioles regulate pressure and veins regulate volume.-