Organized Exam Review PDF

CHAPTER 1: 2 QUESTIONS 1. CMEGROAIMHI a. Cellularity, metabolism, excretion, growth, reproduction, organization, adaptation, irritability, movement, homeostasis, inheritance 2. Feedback a. Positive vs negative feedback i. Snowball example, fores...

CHAPTER 1: 2 QUESTIONS 1. CMEGROAIMHI a. Cellularity, metabolism, excretion, growth, reproduction, organization, adaptation, irritability, movement, homeostasis, inheritance 2. Feedback a. Positive vs negative feedback i. Snowball example, forest fire ii. Running out of gas for the car is not feedback, needs a reaction CHAPTER 3: 3 QUESTIONS 1. Free radicals and antioxidants a. Free radicals:unstable molecules with unpaired electrons. Because electrons prefer to be in pairs, free radicals are highly reactive and seek to stabilize themselves by "stealing" electrons from other molecules, which can cause damage. b. Antioxidants: Antioxidants are molecules that can donate electrons to free radicals without becoming destabilized themselves, effectively neutralizing the free radicals and preventing cellular damage. 2. Enzyme inhibition a. Competitive inhibition is substrate mimicry and active site competition. b. Allosteric inhibition involves binding to a separate site and altering enzyme function through structural changes. 3. Enzymes and substrates (what is false) a. Maltase works on maltose b. Sucrose works on sucrase c. Hydrolysis CHAPTER 4: 4 QUESTIONS 1. Motor molecules: a. Myosin: interact with actin filaments; made of G monomers; intracellular transport (moving vesicles/organelles along actin filaments) b. Kinesin: interacts with microtubules (moves towards + end); transports organelles, vesicles and protein complexes. c. Dynein: interacts with microtubules (moves towards - end, usually the golgi apparatus) d. *intermediate filaments* i. No motor molecules ii. Usually made of keratin protein iii. Functions: reinforce cell junctions; prevent cells from pulling apart; major component in hair and nails CHAPTER 5: 6 QUESTIONS 1. sa/v ratio; what does it mean to increase or decrease it (question is correlated to cell cycle?) a. Decreasing SA/V Ratio: The cell has less surface area relative to its volume, making it harder to transport enough nutrients in and waste out efficiently.  b. Increasing SA/V Ratio: Happens when a cell is smaller, making it easier to manage nutrient and waste exchange. c. When the SA/V ratio becomes too small (as the cell grows large): The cell can no longer maintain its needs efficiently. This triggers signals for the cell to enter the cell cycle and prepare for division. 2. DNA replication (S phase) a. Primase: enzyme that involved in DNA replication i. Brings RNA nucleotides that are complementary to the exposed DNA nucleotides on the template b. Leading strand: new DNA polymer formed on template from the 5’ to 3’ direction c. Okazaki fragment: the other template replicated in short segments away from the replication fork (still in 5’ to 3’ direction) d. Lagging strand: the new DNA polymer formed on the other side of the replication fork 3. Translation: RNA -> protein (last step in central dogma) a. tRNA: transfer RNA: brings amino acids to a ribosome so they can form a protein b. rRNA: ribosomal RNA; structurally reinforces a ribosome any plays a role in linking amino acids together during protein synthesis c. mRNA: messenger RNA; carries a copy of the DNA’s genetic message for protein synthesis from the nucleus to the ribosome d. Methionine: first amino acid used in translation e. Steps of translation: i. Binding mRNA with small ribosomal subunit ii. Formation of ribosome and entry of next tRNA iii. Formation of a peptide bond iv. Translocation v. The stop codon ends translation 4. Transcription: DNA -> RNA (first step in central dogma) Occurs in G1 phase a. Promoter: Region of DNA that initiates transcription b. Steps of transcription: i. RNA polymerase constructs RNA ii. RNA polymerase moves along the DNA template towards the 5’ end iii. Constructs RNA molecule in a 3’ to 5’ direction CHAPTER 6: 9 QUESTIONS 1. Classifying proteins in the body a. By shape: i. Globular ii. filamentous b. functional classification- TRICCS i. Transport ii. Regulatory iii. Immunological iv. Contractile v. Catalytic  vi. Structural c. Location of membrane protein i. Integral ii. peripheral d. Functions of plasma membrane proteins- CCREAM i. Carriers ii. Channels iii. Receptors iv. Enzymes v. Adhesion proteins vi. Markers 2. Osmosis a. Osmotic pressure: tendency of a solution to gain water because of its osmolarity b. Hydrostatic pressure: pressure exerted by water because of its volume or the effect of gravity c. Isotonic: solution has the same concentration of nonpermeating solute particles as the cells cytosol d. Hypertonic: solution has a higher concentration of nonpermeating solute than a cell and causes the cell to lose water e. Hypotonic: solution has a lower concentration of nonpermeating solute particles than the cell and causes the cell to gain water and cell f. Lysis: cells swell so much they rupture 3. type of movement through a membrane requires atp a. Passive transport: does not require energy to move substances across membranes; moves substrates down a concentration gradient i. Simple diffusion: movement directly through the lipid bilayer ii. Facilitated diffusion: movement through specific proteins in the membrane b. Active transport: moves a substrate against a concentration gradient i. Primary active transport: uses energy derived from ATP molecules to change a carrier’s shape in order to move a substrate across a membrane against a concentration gradient 1. Sodium-potassium pump: move Na+ ions out of the cell and K+ ions into the cell 2. Calcium pumps: transport Ca2+ ions out of the cell to maintain a low concentration in the cytosol than the ECF 3. Chloride pumps: transport Cl- ions out of the cell to maintain a low concentration in the cytosol than the ECF ii. Secondary active transport: (indirectly requires ATP)uses the kinetic energy released during facilitated transport of one substance to move another substance through the same carrier protein; a single carrier binds several substrates and transports them through the membrane at the same time; one of these substrates moves down the concentration gradient while the other moves along or against the gradient. c. 4 major ions higher inside vs outside gradients  i. Outside: sodium, calcium, cholrids; inside: potassium 4. Transporting things inside cell a. Endocytosis i. Pinocytosis: cell drinking (cell ingests a small amount of extracellular fluid) ii. Phagocytosis: cell eating (large solid particles) b. Receptor mediated: cell engulfs something because it knows what it is 5. Osmosis a. Which one is hypertonic or hypotonic to the others, which one loses or gains water i. 100 mls of 5% glucose contains less glucose than 120 mls of 5% glucose ii. 100 mls of 5% glucose contains more weight than 100 mls of 0.9% NaCl iii. 100 mls of 5% glucose contains the same concentration of solute as 120 mls of 5% glucose iv. 4% glucose is hypoosmotic to a normal human cell v. 0.9% NaCl solution has the same osmotic pressure as normal blood plasma vi. A 5% glucose is initially isotonic to a human cell, but the cell will swell after remaining in a beaker containing 5% glucose vii. A 5% glucose solution has about the same concentration of diffusible water as a solution with an osmolarity of 300 mOsm/L viii. A solution that is 2.5% glucose and.45% NaCl is isotonic to a human cell ix. Human cells contain less than 300 mOsm/L glucose and less than 0.9% NaCl x. If 25 mL of 5% glucose is mixed with 45 mL of 0.9% NaCl, the new solution would initially be isotonic to a human cell xi. Mixing 200 mls of a 5% glucose with 100 mls of 300 mOsm/L NaCl yields a mixture with NaCl < 150 mOsm/L and glucose > 150 mOsm/L and osmolarity < 300 mOsm/L 6. Things moving in and out of a cell through the membrane a. Channels: tunnels/pores in the membrane that allow specific ions/molecules to pass through based on size/charge; movement is fast (facilitated diffusion) b. Carriers: binding site of specific molecules/ions; slower than channels (facilitated diffusion (passive) active transport) 7. Swelling: caused by a hypotonic solution; the solution has a lower concentration of solute particles than the cell does, so the cell gains water and swells up and can eventually rupture 8. Crenation: cell is shriveling up usually due to a hypertonic solution; the solution has a higher concentration of solute than the cell does so the cell loses water CHAPTER 7: 3 QUESTIONS 1. Part of connective tissue matrix a. Ground substance: the liquid component i. Contains: water, ions, nutrients, metabolites, adhesion proteins, and proteoglycans 2. where you would find certain tissue  a. Loose connective tissues: i. Lamina propria (areolar tissue below a mucous membrane) ii. reticular tissue: branched collagen fibers; forms internal framework of spleen, liver, lymph nodes, and bone marrow iii. Adipose tissue: yellow and brown; armpits, neck and kidney regions b. Endothelium: simple squamous epithelium that lines the inside of blood and lymph vessels : c. Dense connective tissues i. Elastic tissue: elastin protein fibers; blood vessels, lungs, and vocal cords ii. Dense regular: collagen fibers arranged parallely with fibroblasts; tendons and ligaments iii. Dense irregular: irregularly arranged collagen fibers; in the skin and coverings of kidneys, bones and testes CHAPTER 8: 10 QUESTIONS 1. how to make precursors for vitamin d and how it is activated and used to stimulate organs to make proteins 2. Integumentary system a. Hair matrix cells b. Melanocytes & Melanosomes c. Sebaceous glands d. Eccrine sweat gland- merocrine e. Parts of hair & Hair follicle layers f. Pilosebaceous units 3. Fingernail a. Parts b. How it grows 4. What is false integumentary a. Papillary and reticular plexus b. Epidermis- epithelium c. True skin (dermis) is connective tissue, fibroblasts d. Arrector pili- smooth involuntary muscle- only innervated by parasympathetic NS 5. Which pairing has the least related items a. Tissue b. Skin and what things consist of (ie tendons, dermis, etc) c. Tissue cell connections (gap junctions, tight junctions) and their corresponding proteins 6. Process of keratinization in the skin 7. Skin color a. Melanin-relationship b. Melanocytes- relationship 8. Different things in the skin and what they do a. Sweat glands b. Sebaceous glands CHAPTER 9: 10 QUESTIONS 1. Bones growing a. Longitudinal bone growth: bone grows longer at the epiphyseal plate b. Appositional bone growth: bone grows wider; occurs when osteoblasts add matrix to the bones outer surface faster than osteoclasts can remove it. c. Deposition: formation of osseous tissue i. Requires: formation of osteoid secreting bone cells, secretion of osteoid, precipitation of calcium salts in the osteoid to form a hard matrix 1. Steps: development of osteoblasts 2. Secretion of osteoid 3. Calcification of osteoid d. Resorption: destruction of bone matrix and subsequent diffusion of its minerals into the blood; bones minerals are being absorbed into the blood a second time (re) i. Steps: development of osteoclasts ii. Secretion of acids and enzymes iii. Formation of resorption pit (Howship's lacunae) 2. Factors affecting bone growth a. Proteins b. Minerals: calcium, phosphorus, sulfur c. Vitamins: C & D d. Growth hormone: stimulate chondrocytes to make cartilage at epiphyseal discs e. Thyroxine: increases metabolic activity of cells f. Sex hormones 3. Hormones- growth hormone ( stimulates growth plates and promotes osteoblastic activity -> increases deposition) 4. things associated with deposition vs resorption a. Calcitonin: regulate blood calcium levels; increases deposition, decreases resorption b. Piezoelectric effect: certain materials generate an electrical charge when exposed to mechanical stress c. Parathormone d. Acids and enzymes 5. What is false- bone growth a. Intramembranous ossification b. Endochondral ossification c. Growth plates d. Bone matrix e. Inorganic vs organic components 6. Osteons and trabeculae in bone a. Lamella b. Canuclicli c. Central canal 7. intramembranous ossification a. Fontanels  i. Formation of ossification centers: osteogenic cells differentiate to become osteoblasts, which secrete osteoid which calcifies to form trabeculae ii. Development of woven bone: as more ‘non lamellar’ trabeculae emerge, they connect to become woven bone while blood vessels in the fibrous membrane become trapped in between the trabecule iii. Development of lamellar bone and periosteum: periosteum develops as collagen fibers and fibroblasts cluster along the perimeter of the fibrous membrane, osteoblasts continue to form bone matrix iv. Formation of marrow: trabecule grow thicker (spaces between them get smaller) tissue is called spongy bone (diploe) eventually blood vessels give rise to hematopoietic tissue (red marrow) which makes blood cells 8. Factors affecting bone growth a. Proteins, minerals, vitamins, calcium, phosphorus, sulfur, GH, PTH, sex hormones b. Activities of different bone cells i. Osteoclasts: increase resorption ii. Osteoblasts: secrete osteoid, increasing deposition CHAPTER 12: 4 QUESTIONS 1. Joints a. Cartilaginous joint b. Synchondrosis- temporary joint; usually replaced by bone tissue c. Mensici d. Intracapsular and extracapsular ligaments e. Collateral ligaments f. Periodontal ligaments g. gomphosis - special fibrous joint h. Intervertebral disc- nucleus pulposus i. Gomphosis j. Diarthroitc k. Syndesmosis: a fibrous joint in which collagen fibers hold two parallel joints together l. Ampiarthrotic i. Example: tibiofibular ligament m. Suture n. Synovial o. What is not a function of synovial fluid i. Cartilage nourishment ii. Lubrication CHAPTER 13: 1 QUESTION 1. membrane potential a. Action potential: a rapid reversal in polarity, inside membrane becomes positive and outside becomes negative b. Two reversals of polarity c. Ions involved to depolarize or hyperpolarize a membrane CHAPTER 14: 10 1. Smooth muscle a. Single unit= = visceral muscle i. Groups of muscle fibers contract together as one unit b. Multi Unit: each muscle fiber lies next to a varicosity or an axon terminal of a motor neurons c. Visceral organs vs eyeball movement d. Precise vs gross movements ( small vs large muscle movements) 2. Energy for skeletal muscle a. Glycolysis: converts one glucose molecule into two molecules of pyruvic acid and then into lactic acid (build up of lactic acid lowers pH of cytosol and disrupts metabolic reactions and diminishes muscles ability to contract) i. Generates ATP ii. Supplies substrates and energy to mitochondria iii. Occurs with out without oxygen (anaerobic) iv. Muscle fibers can continue to generate ATP long after depleting stores of CP v. Marathons b. Aerobic respiration: slowest method of converting ADP to ATP i. Aerobic ii. Represents final stages of glucose breakdown iii. Breaks down fatty acids and amino acids c. Resting- using lipids d. Moving- glucose 3. Stimulating skeletal muscle a. EMG i. Resting potential ii. Refractory period b. Myogram i. Latent period ii. Contraction period iii. Relaxation period c. Internal tension: force generated within the muscle for contractions d. External tension: the force transmitted from the muscle to the external environment 4. How the brain changes muscle tension- factors affecting muscle tension a. Wave summation i. The effect of successive stimulations on muscle fiber tension ii. Each successive AP initiates a contraction wave larger than the previous b. Motor recruitment i. Small first then large 5. Sliding filament mechanism: Fill in blank i. Sliding filament theory steps: 1. Z discs move closer together  2. I bands become narrower 3. Zones of overlap become wider 4. H zones become narrower 5. Width of A bands remains constant b. Tropomyosin c. Calcium d. Troponin e. Power vs recovery stroke 6. Chapter 14: Different types of muscle contractions a. Isotonic i. Concentric ii. Eccentric b. Isometric 7. Smooth muscle contraction a. Steps: i. Formation of calcium-calmodulin complex ii. Activation of myosin kinase (myosin light-chain kinase) iii. Phosphorylation of light-chain region crossbridge iv. Binding of ATP to ATPase sight v. ATPase activity vi. Binding of crossbridge to actin vii. Cross bridge cycling viii. Relaxation of smooth muscle fiber ix. Latch state b. Must be phosphorylated twice c. Nothing is done to actin CHAPTER 16: 3 QUESTIONS 1. neuroglia a. Glial cells do not conduct impulses- they help neurons conduct impulses faster b. PNS i. Satellite cells: form protective ii. Schwann cells (neurolemmocytes): form myelin sheaths around axons c. CNS i. Oligodendrocytes: make myelin sheaths around axons ii. Astrocytes: maintain homeostasis in ECF; regulate movement between blood and neurons iii. Microglia: engulfs foreign particles (phagocytic) iv. Ependymal cell: ciliated; make CSF 2. Regeneration tubes 3. Neurilemma (sheath of schwann): external, cytoplasmic part of schwann cells 4. Nodes of ranvier (neurofibril nodes): tiny gaps between schwann cells CHAPTER 17: 10 QUESTIONS 1. Where in the NS is gray vs white matter  a. Gray matter: horns, nuclei in the brain, outer surface (cortex) of cerebrum and cerebellum b. White matter: columns, inner regions beneath cortex, corpus callosum 2. Basal nuclei a. What they do b. Recognize name i. Caudate nucleus, putamen, globus palladium 1. Lentiform = globus pallidus and putamen 2. Corpus striatum = caudate nucleus, lentiform c. Semivoluntary motions: ex. Swinging arms when walking 3. Sleep & brain waves a. Stage 1 non rem: alpha b. Stage 2 non rem: irregular c. Stage 3: theta and delta d. Stage 4 non rem: delta e. Rem: skeletal muscle paralysis 4. Parts of the brain and what they do a. Cerebrum: i. Gustatory: insula, perception of taste ii. Olfactory: temporal/frontal lobes, perception of smell iii. Primary auditory cortex: temporal lobe, hearing sounds (volume and pitch) iv. Primary somatosensory cortex: postcentral gyrus, sense of touch and perception of temperature, spatial discrimination v. Primary visual cortex: occipital lobe, perception of light, color, shape, and movement vi. Vestibular cortex: insula, balance and equilibrium vii. Visceral sensory area: insula, perception of sensations from internal organs viii. Auditory association: temporal lobes, interpret/recognize sounds ix. Somatosensory association: post central gyrus, interprets/recognizes touch and textures x. Visual association: occipital lobe, recognizes/interprets visual stimuli xi. Premotor: frontal lobe, muscle memory xii. Primary motor: precentral gyrus, voluntary muscle movement xiii. Broca's area: left frontal lobe, muscle movements for speech xiv. Wernicke's area: parietal/temporal lobes on left side, response to visual/audible stimuli xv. Prefrontal cortex: frontal lobe, intellectual thoughts b. Diencephalon i. Epithalamus 1. Pineal body: melatonin, SAD ii. Thalamus 1. Intermediate mass  2. Geniculate bodies iii. Hypothalamus: controls ANS, regulates limbic system, endocrine system, produces hormones, food/liquid intake, circadian rhythm, body temperature 1. Mammillary bodies c. Brain stem: i. Mesencephalon (midbrain) 1. Cerebral peduncles 2. Superior colliculi: reflexes to visual stimuli 3. Inferior colliculi reflexes to auditory stimuli 4. Substantia nigeria: dopamine (parkinsons) 5. Red nucleus ii. Pons 1. Salivation center 2. Respiratory center 3. Reticular formation iii. Medulla oblongata 1. Decussation 2. Cardiovascular center 3. Respiratory center 4. Deglutition center 5. Emetic center 5. Cerebellum 6. Brain ventricles 7. Functional systems: a. Reticular formation i. Red nucleus ii. Reticular activating system: maintain consciousness b. Limbic system: i. Amygdala ii. Cingulate gyrus iii. Fornix iv. Hippocampus v. Hypothalamus CHAPTER 18: 4 QUESTIONS 1. Cranial nerve, sensory, motor, mixed a. Olfactory: sensory b. Optic: sensory c. Oculomotor: motor d. trochlear: motor e. Trigeminal: mixed f. Abducens: motor g. Facial: mixed h. Verticulochear: mixed  i. Glossopharyngeal: sensory j. Vagus: mixed k. Spinal accessory: motor l. Hypoglossal: motor 2. the sympathetic nervous system does not____ 3. : Reflexes a. withdrawal/flexor reflex i. Receptor: pain/tactile receptor ii. Stimulus: pain/touch iii. Type: polysynaptic iv. Effect: contraction of flexor muscle v. Ex. pain reflex b. Cross extensor reflex (continuation of withdrawal reflex) i. Receptor: pain/tactile receptor ii. Stimulus: pain/touch iii. Type: polysynaptic iv. Effect: contraction of extensor on opposite side of stimulus c. Stretch reflex i. Receptor: muscle spindle ii. Stimulus: muscle stretch iii. Type: monosynaptic iv. Effect: contraction v. Ex. knee jerk d. Reciprocal inhibition: One muscle group (the agonist) contracts to perform a movement, Its opposing muscle group (the antagonist) relaxes to allow the movement to happen. 4. Which of these components would you need for a somatic reflex arc a. Receptor (Sensory Input) i. Detects the stimulus (e.g., pain, stretch) and initiates the reflex. ii. Involves the dorsal root for transmitting sensory signals to the spinal cord. b. Afferent (Sensory) Pathway - "Going In" i. Peripheral Nerve: Carries sensory information from the receptor to the spinal nerve. ii. Spinal Nerve: The mixed nerve that includes both sensory and motor fibers. iii. Ramus: A branch of the spinal nerve that connects to specific regions of the body. iv. Dorsal Root: Transmits sensory input into the spinal cord, the central processing unit. c. Integration Center (Processing in the Spinal Cord) i. Occurs within the gray matter of the spinal cord. ii. The signal may be relayed to an interneuron (in polysynaptic reflexes) or directly to a motor neuron (in monosynaptic reflexes). d. Efferent (Motor) Pathway - "Going Out"  i. Ventral Root: Transmits motor output from the spinal cord to the spinal nerve. ii. Spinal Nerve: Carries the motor signal to the peripheral nerve. iii. Ramus: Sends the signal to a specific body region. iv. Possibly Plexus: If the reflex involves limbs, the motor pathway may pass through a plexus to reach the appropriate muscle. v. Peripheral Nerve: Delivers the motor signal to the effector muscle. e. Effector (Motor Output) i. The muscle or gland that responds to the stimulus (e.g., contraction of a muscle). CHAPTER 19: 4 QUESTIONS 1. ANS a. Preganglionic neurons: the motor neuron that conducts the impulse out of the CNS, then synapses with a postganglionic neuron, has a class B axon b. postganglionic neurons: conducts the impulse along a class C axon c. Neurotransmitters: i. Ach: released by all neurons in the parasympathetic NS ii. NE: fight or flight neurotransmitter d. Receptors: i. Cholinergic receptors: membrane receptors that bind Ach 1. Nicotinic: on all postganglionic neurons in sympathetic and parasympathetic; adrenal medulla; skeletal muscle cells 2. Muscarinic: all muscles and glands stimulated by parasympathetic division; sweat glands and some blood vessels ii. Adrenergic receptors: bind norepinephrine and epinephrine (adrenaline) 1. Alpha: on most cells in the body except cardiac muscle cells a. Alpha 1: binding with NE = excitation b. Alpha 2: binding with NE= inhibition 2. Beta: on cardiac, smoot, and skeletal muscle cells in the liver, kidney, and adipose tissue a. Beta 1: cardiac muscle cells, liver cells, kidney cells; binding with E = excitation b. Beta 2: smooth muscle cells in blood vessels of heart and skeletal muscles; binding with E = inhibition c. Beta 3: on adipocytes; binding with E = excitation -> lipolysis 2. Nerve plexuses a. Brachial: innervation of upper limbs b. Sacral: innervation of lower limbs and some hip structures c. Ventral rami are brought together to form plexuses and then peripheral nerves branch off of those CHAPTER 20: 17 QUESTIONS EYE: 1. Things in the eye, what is false a. Photopigments i. Rods: rhodopsin 1. Scotopsin (glycoprotein) 2. Retinal (vitamin A -> carotene) ii. Cones: iodopsin 1. Photopsins: erythrolabe, chololabe, cyanolabe b. Lens changing shape i. Closer object = round lens, contracted ciliary muscle ii. Far object = flat lens, relaxed ciliary muscle, further than 20 feet 2. What is false about the eye a. Bleaching photopigments b. Photoreceptors hyperpolarize in order to see c. cones, rods, wavelengths d. Regenerate and bleach constantly e. Photoreceptor and bipolar cells f. Saccadic eye movement- quick and jerky 3. Eye a. Accommodation b. Photoreceptors c. Depolarization or hyperpolarization d. Afterimaging e. Saccadic eye movement f. Visual acuity- lens accommodation 4. Lens accommodation a. Far vision = loose ciliary muscle and flat lens b. Near vision = taught ciliary muscle and round lens c. Suspensory ligaments function: hold lens in place 5. Eyeball anatomy which of the following is farthest away from ____ 6. Fluid in eyeball a. Aqueous humor: i. Location: Found in the anterior chamber and posterior chamber of the eye, between the cornea and the lens. ii. Function: 1. Nutrient delivery: It provides nutrients to the avascular structures (cornea and lens), as these parts of the eye don’t have their own blood supply. 2. Waste removal: It helps in removing metabolic waste from the lens and cornea. 3. Intraocular pressure (IOP): It helps maintain the pressure inside the eye, known as intraocular pressure. iii. Production: The aqueous humor is primarily produced by the ciliary body, specifically by the epithelium of the ciliary processes. It is formed from  blood plasma but is filtered and modified to form the clear, watery fluid that is rich in nutrients like glucose and amino acids. iv. Draining: The aqueous humor drains out of the eye through a network called the trabecular meshwork, located at the angle where the cornea and iris meet (known as the anterior chamber angle). From the trabecular meshwork, it flows into the Canal of Schlemm (a circular canal), which empties into the bloodstream via veins. b. Vitreous humor: i. Location: Found in the posterior segment of the eye, between the lens and the retina. It fills the large cavity of the eye and helps maintain its shape. ii. Function: 1. Shape maintenance: It helps maintain the spherical shape of the eye and keeps the retina in place by exerting pressure against it. 2. Light transmission: It is a transparent gel-like substance that allows light to pass through to the retina for vision. 3. Shock absorption: It acts as a cushion for the retina, protecting it from mechanical shocks. iii. Production: The vitreous humor is mostly formed during embryonic development, and unlike the aqueous humor, its production is minimal after birth. It is composed mostly of water, along with collagen fibers, hyaluronic acid, and other molecules that give it a gel-like consistency. iv. Draining: The vitreous humor is not drained in the same way as the aqueous humor. Instead, it remains in the eye throughout life, though it can slowly undergo changes. 7. What is false about the eye a. Photoreceptors and photopigments b. Sensitivity of photopigments (dim vs bright light) c. Iodopsin and rhodopsin, colors, photopsin EAR 1. Hearing a. Transmit soundwaves through external ear to inwards i. External Ear: The sound waves first enter the ear through the pinna (auricle) and travel through the external auditory canal. The pinna helps to funnel sound waves into the ear canal, where they are amplified slightly by the shape of the ear. ii. Tympanic Membrane (Eardrum): The sound waves then strike the tympanic membrane, causing it to vibrate. The vibrations correspond to the frequency and amplitude of the incoming sound. b. Creating vibrations: the vibrations from the eardrum are transferred to the three small bones in the middle ear, called the ossicles:Malleus (hammer)Incus (anvil)Stapes (stirrup) These bones act as levers to amplify the vibrations and transmit them to the oval window, which is the entrance to the inner ear.  c. Organ of corti: contains hair cells, which are sensory receptors. When the basilar membrane moves, the hair cells (which are embedded in the tectorial membrane) bend in response to the movement. This bending opens ion channels in the hair cells, generating electrical impulses (action potentials). These electrical signals are then transmitted to the brain via the auditory nerve. d. Vibrations in the Inner Ear and Cochlea: i. Oval Window: the stapes (the last ossicle) pushes on the oval window, a membrane-covered opening that leads into the cochlea of the inner ear. The oval window transmits the vibrations into the fluid-filled cochlea, where the vibrations create pressure waves in the cochlear fluid. ii. Cochlea:The cochlea is a spiral-shaped, fluid-filled structure that contains the Organ of Corti, the actual sensory organ for hearing. The fluid pressure waves inside the cochlea cause the basilar membrane to vibrate. The Organ of Corti, located on this membrane, contains hair cells that respond to these vibrations. e. Spiral, higher pitch vs lower pitch windows, helicotrema: i. Spiral Shape and Frequency Detection: 1. The cochlea is organized in a way that it responds to different sound frequencies in different regions: a. High-frequency sounds cause vibrations at the base of the cochlea (near the oval window). b. Low-frequency sounds cause vibrations at the apex of the cochlea (near the helicotrema, a small opening at the apex of the cochlea). 2. This phenomenon is called tonotopic organization: different areas of the cochlea respond to different pitches. ii. Helicotrema and Frequency Range: 1. The helicotrema is the small opening at the apex of the cochlea that connects the two ducts within the cochlea (the scala vestibuli and scala tympani). 2. Low-frequency sounds travel further along the cochlea, reaching the helicotrema, while high-frequency sounds are detected near the base of the cochlea. iii. Vibrational Properties of the Basilar Membrane: 1. The basilar membrane has varying stiffness along its length: a. The base (near the oval window) is stiff and responds to high-frequency sounds. b. The apex (near the helicotrema) is more flexible and responds to low-frequency sounds. 2. What is false a. Inner ear b. Hearing c. Cochlea part of the body labrinth d. Membranous labyrinth  e. Cochlear or corti- contains organ of corti f. Three chambers g. Short wavelength = high pitched h. Height of waves = intensity=decibels=logarithmic 3. Ear a. Balance and equilibrium in inner ear i. Static equilibrium It is concerned with maintaining posture and orientation when you're not moving or only slightly moving. 1. Organ Involved: The primary organ responsible for static equilibrium is the vestibule of the inner ear, which contains two structures:Utricle Saccule a. The utricle and saccule are filled with a gelatinous substance and contain small hair cells embedded in it. Over the hair cells is a layer of otolithic membrane, which contains tiny calcium carbonate crystals called otoconia. b. When you move your head (such as tilting it), the otoconia shifts due to gravity, causing the otolithic membrane to move. This movement bends the hair cells, which generates nerve impulses that are sent to the brain, informing it about the position of your head relative to gravity (whether your head is upright, tilted, etc.). ii. Dynamic equilibrium: Dynamic equilibrium refers to the sense of balance that helps you detect changes in motion and the position of your head when you are moving, particularly when it comes to rotational movements. 1. Organ Involved: The semicircular canals are responsible for dynamic equilibrium. There are three semicircular canals: Anterior canal Posterior canal Lateral (horizontal) canal 2. How it works: a. Each semicircular canal is oriented in a different plane (one for each of the three axes of rotation: pitch, yaw, and roll). b. Inside each canal is a structure called the ampulla, which contains a cluster of hair cells embedded in a gelatinous mass called the cupula. c. When you rotate your head, the fluid (endolymph) inside the semicircular canals moves, which causes the cupula to bend. This bending of the cupula moves the hair cells, generating nerve impulses that are sent to the brain. d. The brain interprets the direction and speed of the head’s rotation, allowing you to maintain balance while moving, such as when turning your head, spinning, or in response to changes in the velocity of movement. 4. Pain:  a. Phasic b. Referred c. Phantom d. Chronic e. Tonic 5. smell/taste a. Olfactory neurons- replaced every two months b. Sustentacular cells: compose tongue papillae c. Basal cell: d. Cribriform plate e. Ethmoid bone