Bio Unit 5 Endocrine and Nervous System PDF

Unit 5 Endocrine and Nervous Systems Endocrine System: secretes hormones which regulate a variety of metabolic processes -​ Ductless glands which secrete hormones -​ Ductless: do not have a tube/vessel for which the hormone passes -​ Can get away without ducts because generally secrete hormon...

Unit 5 Endocrine and Nervous Systems Endocrine System: secretes hormones which regulate a variety of metabolic processes -​ Ductless glands which secrete hormones -​ Ductless: do not have a tube/vessel for which the hormone passes -​ Can get away without ducts because generally secrete hormone into the lymphatic system and circulatory system -​ Straight to target organ Endocrine Glands: -​ Head -​ Hypothalamus -​ Pituitary gland -​ Pineal gland, melatonin -​ Neck -​ Thyroid -​ Parathyroid: 4 little glands -​ Thoracic -​ Thymus -​ Abdominal -​ Pancreas: endocrine and exocrine (have tubes/ducts where their secretory products/enzymes are release), insulin and glucagon -​ Adrenal glands: on top of each kidney, 2 in one, inner and outer parts -​ Gonads -​ Ovary, estrogen, progesterone -​ Testicles, testosterone -​ Placenta only during pregnancy Hormone: chemical messengers that influence the metabolism of recipient cells Peptide Hormones: activate enzyme systems, require a “second messenger,” oxytocin and epinephrine, protein Steroid Hormones: testosterone, estrogen, lipid, cell membrane is a phospholipid, can enter cells, activate certain DNA, transcription and translation Hypothalamus and Pituitary Glands: -​ Underside of the brain -​ Pituitary: secrete hormones that affect every aspect of our biology, diversified functions, “master gland” -​ Hormones  -​ TSH: thyroid stimulating, pituitary hormone, secreted into the blood, stimulates the thyroid to secrete its hormones -​ *Trophic means secreted by one gland, to stimulate change in another gland -​ ACTH: adrenocorticotropic hormone, stimulates the adrenal glands, the cortex (outer cortex) -​ FSH and LH: follicle stimulating hormone stimulated one follicle to begin to develop and mature, luteinizing hormone about 2 weeks in to cycle spikes and causes the follicle to rupture and release the egg (ovulation), important in reproductive system, in males it plays a role in maturation and sperm production -​ Somatotropic/Growth Hormone: controls our overall growth and development -​ PRL Prolactin: stimulates the production of milk in the mammary glands, oxytocin in that causes the smooth muscle contractions which release the milk -​ Endorphins: natural pain killers, something that we perceive that something is wrong in our body, the pain is acute initially and then the pain might subside from the endorphin release, trauma=athletics -​ MSH Melanocyte Stimulating hormone: cells in skin that produce melanin, under hormonal control, as exposed to more UV releases MSH to release more melanin Effect of Growth Hormone: -​ Controls every aspect of human growth and development -​ Bone and muscle -​ Excess: can stimulate more -​ Makes bone denser and increases muscle mass -​ Hypothalamus: below, region of the brain below the thalamus, sensory info arrives and is then channeled to the correct center for analyzing, controls most aspects of pituitary and when it releases hormones, controls homeostasis (body temp, oxygen content), -​ Oxytocin effects are to stimulate smooth muscle contraction, during labor, uterine muscles, -​ ADH (antidiuretic) conserves water and controls urine, are produced in hypothalamus but stored in pituitary -​ Releasing factor hormones, which controls when pituitary releases hormones and which ones to release, sense of hunger, thirst Thyroid Gland:  -​ Located in the throat region -​ Parathyroid gland -​ Thyroxine (T4), metabolism, 4 atoms of iodine per molecule, 90% of total secretion -​ Triiodothyronine (T3), metabolism, 3 atoms of iodine per molecule, 9-10% secretion -​ Calcitonin -​ Require iodine to produce hormones -​ Speed up metabolism -​ Without iodine, cannot produce hormones -​ Low iodine => goiter -​ Calcitonin Hormone: controls calcium balance in the body, lower calcium levels in the blood, increases the uptake of calcium from the blood, stores -​ Parathyroid hormone: increases calcium level, breaks down calcium and releases it into the blood, raises calcium levels, it stimulated when there are low calcium levels -​ To break down and rebuild it again for bones -​ Calcium has an electrolyte as an ion (for contracting muscles, secretion of the neurotransmitters by nerve cells, stimulates ) -​ If excess calcium it stores it in the bone Parathyroid Gland: -​ Secrete parathyroid hormones -​ To raise blood calcium levels from the dissolving bone matrix Calcium Balance: -​ Negative feedback loop to maintain homeostasis -​ Calcium rises and is rich in calcium => calcitonin is secreted into the bone matrix levels fall -​ If fall below critical point then parathyroid will be be released by dissolving the bone matrix Adrenal Gland: -​ Located on top of each kidney -​ Positive feedback response -​ 2 glands in one -​ Outer is called cortex -​ Inner part is call the medulla -​ Allow to monitor stress in short and long term Adrenal Cortex: -​ Glucocorticoids (cortisol): inhibits aspects of the immune system (suppresses it), the inflammation response produces vasodilation and allows antigens to flow around capillaries, stimulates the liver to break down proteins and fats and convert them to glucose.  -​ Mineralocorticoids (aldosterone): an antidiuretic, stimulated kidney to release less urine, release potassium, retain more water, higher blood pressure -​ Sex hormones -​ Long term stress response Adrenal Medulla: -​ Epinephrine and norepinephrine: adrenaline, produced by many of the nerve cells, hormone and neurotransmitter, releases epinephrine and then -​ Short term stress response Pancreas: -​ Exocrine and endocrine gland -​ Insulin: lowers blood glucose levels, both are absorbed from the circulatory system and can be stored inside cells in the body -​ Glucagon: raises blood glucose levels -​ Negative feedback loop Testes: -​ Testosterone: responsible for inducing the secondary sexual characteristics Ovaries: -​ Estrogen: responsible for inducing the secondary sexual characteristics -​ Progesterone: briefly in the cycle and extended during pregnancy Thymus Gland: -​ Located in the chest -​ Produces T-Cells -​ Thymosin -​ Large during childhood and then it decreases in size as humans get older -​ Atrophies and activates less t cells as older -​ This makes it easier for old people to get sick Pineal Gland: -​ Located in the center of the brain -​ Secretes melatonin -​ Regulates sleep cycles -​ Circadian rhythm Digestive Hormones: -​ Gastrin: stimulates cells to produce gastric juice -​ Secretin: from small intestine, stimulates pancreas to secrete pancreatic juice -​ Cholecystokinin: produced by small intestine, stimulates secretion of pancreatic juice and releases and flow of bile from gallbladder Vertebrate Nervous System: -​ Nervous system controls responses to the external environment and coordinates functions of internal organs -​ nerve= bundle of nerve cells -​ Central Nervous System (CNS) -​ Brain -​ Spinal cord -​ Peripheral Nervous System (PNS) -​ 12 pairs of cranial nerves plus 31 pairs of spinal nerves -​ Sensory (afferent division) -​ Somatic sensory neurons => sensory information from skin, muscles, joints -​ Visceral sensory neurons => sensory information from internal organs -​ Motor (efferent division) -​ Somatic => voluntary, conducts impulses from CNS to skeletal muscles -​ Autonomic => involuntary, conducts impulses to cardiac muscles, smooth muscles and glands -​ Sympathetic Division: fight or flight response, speeds up -​ Parasympathetic System: rest response Neuron: -​ A nerve cell/fiber -​ Structure -​ Axon: cytoplasmic extensions, carry impulses away from the nerve cell body -​ Dendrite: cytoplasmic extensions, carry impulse towards the nerve cell body -​ impulse from dendrite to nerve cell body to axon, then into axon terminals synaptic end bulbs where the neurotransmitters are stored, never really touches another nerve cell a synapse gap -​ Myelin Sheath: fatty sheath, insulates, function to speed the nerve impulse up, myelinated axon, can skip to other nodes -​ Schwann cell: glial cells, support the nervous system, secreted the myelin sheath -​ Nodes of Ranvier: a gap in the myelin sheath that doesn’t cover the axon membrane, speeds up the rate that the impulse is transmitted -​ Telodendria: reaching to the next dendrite or skeletal muscle (basically the same as the axon terminal) Nerve Impulse: -​ Sodium/Potassium pump -​ Active transport: involves ATP, high energy molecule, 3 phosphate groups -​ At rest, sodium is active transported out of the nerve cell, potassium is actively transported into the cell  -​ This is to set up a concentration gradient: the process of particles, which are sometimes called solutes, moving through a solution or gas from an area with a higher number of particles to an area with a lower number of particles. -​ Used to generate nerve impulse -​ Charged Gradient: -70mv resting membrane potential, the charge difference is what generates the impulse more on inside than outside, a combination of an electrical potential difference and a concentration gradient -​ The difference in sodium and potassium creates enough potential energy to produce a nerve impulse 1.​ Depolarization -​ A neurotransmitter needs to attach to the -​ Resting state -​ Action potential is synonymous with nerve impulse -​ 2.​ repolarization -​ Potassium rushes out to return cell to resting state Neurotransmitters: 1.​ Acetylcholine: neuromuscular function, 2.​ Biogenic amines (from amino acids) a.​ Tyrosine i.​ Epinephrine ii.​ Norepinephrine iii.​ Dopamine iv.​ Serotonin b.​ GABA (gamma-aminobutyric acid): within the brain, inhibitory c.​ Glycine (CNS but outside of the brain), inhibitory 3.​ Nitric Oxide (NO): formed on demand, can diffuse from one nerve cell to another, Dopamine: -​ Reward -​ Motivation -​ Pleasure -​ Motor function -​ Parkinson’s disease Serotonin: -​ Sleep -​ Memory function Reflex Arc: -​ Unaware bc it hasn’t reached the brain yet -​ 1.​ Sensory receptor: arrival of stimulus and activation of receptor, ouch 2.​ Sensory neuron: carries information to the spinal cord 3.​ Interneuron (association neuron): may or not be involved, nerve cell that synapses with the sensory and motor neuron 4.​ Motor neuron: nerve cell that carries info back to a skeletal muscle to contract 5.​ Effector: the muscle that carries out the effect, the contraction Brain Structure and Function: 1.​ Cerebrum: most recent ⅞ of the brain, interpretation of the information, cognition, association a.​ Cerebral hemispheres b.​ Ventricles: chambers filled with cerebrospinal fluid giving glucose c.​ Meninges: 3 membranes, cerebrospinal fluid is through that d.​ Cerebrospinal fluid e.​ Functional Regions: higher order thinking skill in the cerebrum, primary cortex (vision, getting basic info of interpretation, color, size, texture), Visual association area (sends fibers out in the storage area and retrieves a memory to understand the information), premotor area (determines what muscles have to be used for the action), primary auditory cortex (volume, pitch), auditory association area (understanding the sound through the limbic system), prefrontal area (motivation, focus, drive) f.​ Brain Lateralization: the left side controls motor functions on the right side of body, and vice versa 2.​ Corpus callosum: band of tissue, nerve fibers that extend into the L and R to connect hemispheres w/ connections, part of the limbic system 3.​ Cerebellum: 2nd oldest, complex movements (walking/running), make it almost involuntary, balance, makes movement smooth, 4.​ Medulla oblongata: oldest part, heartbeat, respiration 5.​ Thalamus: sensory relay area, all except for smell pass through it first and then it goes to the cerebrum, 6.​ Hypothalamus: below thalamus, connected to pituitary gland, endocrine gland, ADH and oxytocin, urges like hunger and thirst, center for homeostasis 7.​ Limbic System: our emotional brain, unique personalities, amygdala and hippocampus, memory retrieval, amygdala and hippocampus  8.​ Reticular Activating System: based in the brain stem, branches into the entire brain, awakens and maintains consciousness, filters out information, Peripheral Nervous System: -​ 12 cranial -​ 31 pairs of spinal nerves -​ Involuntary => autonomic nervous system (controls ) and sematic Parasympathetic: -​ Rest and repose, normal resting state functions -​ Closes the iris and pupil gets smaller -​ Slows heartbeat -​ Stimulates peristalsis -​ Longer preganglionic fibers and shorter postganglionic fibers -​ From the 3 cranial and 2 sacral nerves Sympathetic: -​ Fight or flight response -​ Dilates pupil (to allow more light and to see better) -​ Accelerated heart rate -​ Decreases peristalsis -​ Short preganglionic fibers and longer postganglionic fibers -​ Thoracic and lumbar Eye Anatomy: -​ Outer part is sclera (white of the eye, tough protein same protein as cornea) -​ Choroid (vascular tissue, blood supply of the eye) -​ Retina: inner lining of the eye, lined with photoreceptors/sensory receptors (rods and cones) -​ Cornea: -​ Anterior Chamber: front chamber, filled with fluid called aqueous humor, constant produced and drained -​ Iris: smooth muscle, pigmented, can expand and contract, eye color -​ Posterior Chamber: filled with vitreous humor, more of a gel like material, more constant -​ Pupil: opening -​ Lense: -​ Inner Lining: retina -​ Optic nerve -​ Fovea: the focal point, the area where there is the highest concentration of rods and cones, -​ Everytime light passes through, it bends and refracts and then it focuses the light  -​ Path: cornea, aqueous humor, iris, passes through pupil, lense, vitreous humor, most of the light waves will concentrate on fovea -​ Rods: sensory receptors, pick up dim light, night vision, -​ Cones: color vision, red, green, and blue, the number that fire simultaneously Pathology of the Eye: -​ Males are more likely to be colorblind -​ Color blindness: sex linked trait -​ Myopia: nearsightedness, distance is blurry, the light is refracting but the eye is too long or there is a problem where the focal point is in the middle without the concentration of rods and cones, which causes the blurry image -​ Hyperopia: farsightedness, eye is too short or a problem with a lense, by the time the light waves meet the back of the eye they have not converged yet at the focal point -​ Astigmatism: the cornea is abnormally shaped, which scatters the light waves -​ Cataracts: effects the lense (transparent protein), over time the protein breaks it down and it loses the parts of the protein, which makes it less transparent and cloudy to where light cannot get through -​ Glaucoma: a problem with intraocular pressure, with it being too high, damages optic nerve, too much aqueous humor and it cannot drain properly, and increases pressure on the retina and can cut off the blood supply to the photoreceptors/retina which can cause blindness Ear Anatomy: -​ Sound waves: composed of vibrations of molecules in the air around us -​ 3 areas: outer, middle, inner -​ Outer -​ Pinna: channels the soundwaves -​ auditory/ear canal: channels the soundwaves and starts vibrating as the same frequency inside the ear drum -​ End is marked by tympanic membrane (eardrum) -​ Middle -​ 3 ossicles/bones: all start to vibrate at the same frequency -​ malleus (hammer): -​ incus (anvel): -​ stapes (stirrups): creates waves in the cochlea apparatus -​ Oval window: thin area in the wall of the middle and inner that each time the stirrups move then it touches the oval window -​ Round window: release valve, prevents the membrane from rupturing easily -​ Eustachian Tube: balances the pressure from outside -​ Inner  -​ Cochlea: creates nerve impulses that will be , hearing, fluid filled chamber, lower pitches are at the very end of the cochlea and it is increasing towards the outside, -​ Organ of Corti: transduction from wave to nerve impulse, membrane that is lines with special cells that have cilia connected to them, attuned to certain frequencies, bend to certain frequencies -​ 3 semicircular canals: work with waves, function in balance and equilibrium, fluid is self contained, dynamic equilibrium when balancing while moving, static equilibrium while sitting Reproductive Systems and Human Development Unit 6 Mechanisms of Sexual Reproduction -​ External fertilization: eggs shed and fertilized externally, aquatic animals and amphibians, jelly like membrane, no shell, a lot of eggs -​ Internal Fertilization: sperm and egg unite within reproductive tract, reptiles birds and mammals, covered with calcareous (hard shell), small numbers of eggs -​ Oviparity (egg laying) and ovoviviparity (egg is inside, hatch inside and live birth) -​ External fertilization provides less parental protection but possibility for greater variation Protection of Embryos -​ Gelatinous egg coat: fish and amphibians -​ Amniotic egg: self contained, modern birds, and reptiles, amnion (filled with fluid), yolk sac (nourishment for the embryo), allantois (collects waste products), chorion (for gas exchange) -​ Mammals: has small yolk sac, allantois => umbilical cord, amniotic sac -​ Monotremes -​ Marsupials -​ Placental mammals Male Reproductive Anatomy: -​ Testes -​ Many seminiferous -​ Spermatocytes diploid cell to haploid cells -​ Sertoli cells (provide nutrients to sperm cells) -​ Leydig/interstitial cells (produce testosterone) -​ Miosis which forms sperm cells -​ Fructose is produced (the only place in the body) instead of sucrose  -​ Epididymis: the sperm mature 2 week period -​ Deferens: mixed with seminal fluid -​ Urethra: metabolic waste -​ 2 seminal vesicles/glands -​ Prostate gland (), between vas deferens and urethra -​ Calpers/bulbourethral gland: produces the 1% fluid, lubricant Anatomy of a sperm cell: -​ Only cell in human anatomy that has a flagellum -​ Head: tip (acrosome, contains digestive enzymes (lysosomes) which dissolved the gelatinous coating of the egg sell), contains 1 set of chromosomes -​ Midportion: mitochondria, produces the ATP from fructose for energy -​ Tail: flagellum -​ Fluid: mucous, amino acids, more fructose, prostaglandins (cause ripple like contractions of the uterus to facilitate), 60% seminal fluid, 40% prostate gland, alcolyn (raises ph of the fluid and the ph in the female reproductive tract to facilitate the sperm movement) Female Reproductive System: -​ Ovaries and testes are made from the same tissue -​ Cervix entrance -​ Uterus -​ Endometrium: lining of uterus -​ Vagina -​ Follicles -​ Fimbria: -​ Corpus luteum -​ Oviduct/fallopian tubes -​ Ovaries: born with all we will ever make -​ Distal end of fallopian tubes is when fertilization happens Anatomy of Ovary: -​ Follicles: immature egg cell -​ LH peaks and stimulates the follicle and it releases/ -​ Floating between ovary and entrance for fallopian tube -​ Old follicle becomes temporary endocrine gland (corpus luteum) which starts producing progesterone -​ Progesterone controls every aspect of the pregnancy -​ Corpus luteum has less than a 2 week period if no fertilization and then the uterine lining sheds  -​ Fimbriae contract to pull fluid and pull the egg into the fallopian tube -​ Fallopian tube is lined with cillian tubes and creates a current to direct the egg -​ Ectopic pregnancy: when it the fertilized egg gets stuck, succeptical if have endometriosis -​ Multiple sperm cells have to break down the outside and whichever sperm cell gets there first will be the fertilization -​ Zygote (fertilized egg) -​ 2, 4, 8 cell stage all called cleavage divisions day 3 -​ Morula is no bigger than original egg cell but has all 16 cleavage divisions day 4 -​ 64 cells day 5 morula expands to hollow ball (blastula) -​ Day 6 late blastula/blastocyst -​ Day 7 implantation -​ Gastrulation: blastula folds in on one side which forms the digestive tract of the mammal, deuterostomes -​ Gastrula: 3 germs layers have developed Day 9-10 Endoderm Layer Becomes: -​ Digestive system -​ Liver -​ Pancreas -​ Lungs (inner layer) Mesoderm Layer Becomes: -​ Circulatory system -​ Lungs (epithelial layers) -​ Skeletal system -​ Muscular system Ectoderm Layer Becomes: -​ Hair -​ Skin -​ Nails -​ Nervous system Look back at how hormone levels change throughout the menstrual cycle HCG Humanchoriongonadotrophic Feedback with ovary Within the placenta Tells the body that there is a pregnancy