KIN 370 FINAL EXAM REVIEW NOTES PDF

Special Senses ✔ Higher-Order Neural Functions ✔ Endocrine System Testosterone - guest slides QUESTIONS Special Senses: Eyelashes: Why are eyelashes considered essential for eye protection? - They protect your eye from dirt, debris, and other irritants...

Special Senses ✔ Higher-Order Neural Functions ✔ Endocrine System Testosterone - guest slides QUESTIONS Special Senses: Eyelashes: Why are eyelashes considered essential for eye protection? - They protect your eye from dirt, debris, and other irritants Eyelid Glands: How do tarsal glands contribute to maintaining eye health, and what would happen if they malfunctioned? - They are sebaceous glands that are along the inner margin of the lid. They prevent your eyelids from sticking together, so if they malfunction then it could cause dry eyes or cause your eyelids to stick together. Tear Pathway: Why is the specific pathway of tear production and release critical for eye health and function? - Lacrimal gland ⇨ lacrimal ducts ⇨ lacrimal canal ⇨ Nasolacrimal duct ⇨ Nasal Cavity - This pathway makes sure it is a continuous and balanced delivery for tears/fluid across the ocular surface which also provides lubrication, protection, and nutrients to the cornea and conjunctiva. Eye Muscles: How do the rectus and oblique muscles work together to enable eye movements? - Rectus muscles are responsible for moving our eyes up, down, left and right. The oblique muscles are responsible for moving our eyes in a circular motion. Eye Layers: What roles do the vascular, fibrous, and retinal layers of the eye play, and how do they interact? - Fibrous Layer (most outer layer) ⇨ provides structural support and protection for the eye by maintaining its shape through the tough, white sclera, while the transparent cornea at the front allows light to enter. - Mechanical support and protect - Attachment site for muscles - Assists in focusing - Contains = sclera, cornea, and corneal limbus - Vascular layer (middle layer) ⇨ supplies blood to the outer layers of the retina through the highly vascularized choroid, and regulates the amount of light entering the eye by the iris. - Blood and lymphatic circulation\  - Regulates light entering pupil - Produces and drains aqueous humor - Focuses the lens - Contains = choroid, ciliary body, iris, and pupil - Retina layer (Inner layer) ⇨ Detects light and converts it into electrical signals that are sent to the brain via the optic nerve. - Neural layer = inner - Pigmented layer = outer - Optic disc = origin of optic nerve - Photoreceptors ⇨ rods and cones - Network of neurons receiving information from photoreceptors - Contains = Fovea and optic disc - Interactions ⇨ They all work together to protect the eye, provide blood supply to the retina, and convert light into visual signals using the optic nerve. Sclera: What structural and functional advantages does the sclera provide to the eye? - It's made of a thick fibrous layer and the functions include extrinsic muscle insertion, blood supply, and protection/support. It also helps maintain your eye shape and protects it from injury! Low Light Vision: Why are rods more effective than cones in low light conditions, and how does this affect vision clarity and color perception? - Rods are more effective in low light conditions because they receive information about light and create a grainy image. Cones aren’t effective in low light conditions because it needs a lot of light to give us information about color to create a sharper image. Optic Nerve Formation: Which cells integrate visual information before transmitting it through the optic nerve? - Ganglion cells are the last neurons before the information gets sent to the optic nerve. The ganglion cells receive information from bipolar cells. Sharpest Vision: Why is the fovea adapted for sharp vision, and what structural features support this? - The fovea is the area of highest concentration of cones. Cones allow us to receive color information to create a sharp image. Taste Receptors: How might water taste receptors play a role in hydration and survival mechanisms? - Ear Pressure: How does the auditory tube maintain balance in ear pressure, and why is this important for hearing? - The auditory tube maintains balance by allowing air to flow in and out of the middle ear. This equalizes pressure between the middle ear and the outside environment. This  is important for hearing because it allows the eardrum to vibrate properly and transmit sound waves to the inner ear. Rotational Movement: How do the semicircular canals detect rotational movement, and what challenges might occur if they malfunction? - It can detect rotational movement by using fluid inside the canals called endolymph. This fluid moves when your head rotates. This also causes the hair cells within the canals to move and send signals to the brain about the direction and speed of head movement. If malfunction occurs in the semicircular it can cause dizziness, vertigo, balance problems, etc. Olfactory Tissue: Why is the olfactory epithelium critical for the sense of smell, and how does it work in concert with other sensory systems? - It is critical for sense of smell because it contains receptor cells and basal cells that are called olfactory sensory neurons that detect odor molecules. They also transmit the information to the brain using the olfactory nerve (#3). Gustation Sensitivity: How do different circumstances, such as illness or aging, affect the sensitivity of taste perception? - Our taste buds start to decline at age 50 so when we get older our olfactory taste and smell arent working at 100% which affects our sensitivity to foods. Hearing Structure: Why is the cochlea uniquely suited for converting sound waves into neural signals? - It's suited for converting sound waves into neural signals because it allows different frequencies that come in from the oval window to stimulate specific areas along the spiral. Endolymph: What role does endolymph play in maintaining balance and hearing, and how might issues with this fluid cause vertigo? - Endolymph is located in the inner ear and its function is to maintain balance and hearing by allowing the detection of head movements via the semicircular canals which then sends the signals to our brain. If there are issues with our endolymph it can disrupt signals which can lead to vertigo. Vertigo is a sensation which causes dizziness or spinning because the brain is not receiving the correct information about balance. Conjunctiva Inflammation: What are the common causes and treatments for conjunctivitis, and how can it be prevented? - Conjunctivitis is also known as pink eye and its inflammation. The main causes include infections, allergies and irritants. The common treatments are antibiotics/eye drops because it is contagious! It can be prevented by washing your hands, avoiding touching/rubbing your eyes, not sharing towels, pillowcases, makeup or glasses, cleaning your bed and other surfaces, and cleaning your contact lenses. Iris Opening: How does the pupil size adjust to changes in light, and what mechanisms control this adjustment? - The muscles in the pupil contract the iris which constricts the pupil in bright light or dilates the pupil in dim light. This mechanism is automatic and is controlled by the pupillary light reflex with the parasympathetic nervous system (constricts for normal function) and sympathetic nervous system (dilates for fight or flight). Sharp Vision Structures: How do cones contribute to sharp vision and color differentiation? - The eye has three different types of cones and each one of them is sensitive to different wavelengths of light. The red cones are sensitive to long wavelengths, green cones are sensitive to medium wavelengths, and blue cones are sensitive to short wavelengths. This allows for a wide range of colors through signals from these photoreceptors. Blind Spot: Why does the optic disc create a blind spot, and how does the brain compensate for this in visual perception? - The optic disc creates a blind spot because this is where the optic nerve is located on the retina. This area also lacks photoreceptor cells which help detect light, so no visual information can be gathered from the blind spot. The brain compensates for this by “filling in” the missing information based on surrounding visual details from the other eye. Vitreous Body: How does the vitreous body contribute to maintaining the eye’s shape and overall function? - It provides structural support and volume acting as an internal scaffold that prevents the eye from collapsing. The vitreous body is clear/transparent so it allows light to still pass through and reach the retina which helps with the function of visual information. Motion Sensing: How does the vestibule allow for the sensation of motion when stationary, such as in a moving car? - The functions of the vestibule is to sense gravity and linear acceleration. This is why we are able to feel when your body is moving, for example in the car. The vestibule contains otoliths which are gelatinous structures containing crystals which contain hair cells. These shift position when you decelerate or accelerate which stimulates the hair cells and sends signals to the brain even if you can’t visually see that you are moving. Retinal Layers: What functions do the choroid and vitreous body serve in keeping the retina intact and functional? - The choroids function is to supply the retina with nutrients and oxygen through blood supply. The vitreous body’s function is to act as support structure which helps keep the retina in place while maintaining the shape of the eye. Higher-Order Neural Functions Memory Formation: What processes underlie long-term potentiation, and why is it essential for memory formation? - Long-term potentiation is a synaptic model for learning. A dense cluster of rapid action potentials will result in that synapse becoming hyperresponsive or potentiated (these changes are long-lasting). Memory Recall: How do primary, secondary, and tertiary memories differ in retention and recall, and what factors influence these? - Secondary memories are those that fade with time and sometimes require significant effort to recall. - Tertiary memories are those that stay with you for a lifetime (unless there’s a pathology). Memory Duration: What distinguishes long-term memories from short-term memories in terms of formation and retrieval? - Short-term memories are those that last less than an hour and the information can be recalled immediately. - Long-term memories are those that last longer than an hour. The conversion from short-term to long-term memories is called memory consolidation or LTP. Higher-Order Neural Functions: Why does the cerebral cortex play a critical role in higher-order neural functions, and what happens if it is damaged? - The cerebral cortex is one of the main regions responsible for learning and memory. Most of our long-term memories are stored in the cerebral cortex. If the cerebral cortex is damaged then your memory can also be damaged and incomplete. Skill Memory: What neurological processes are involved in developing and refining skill-based memories like playing an instrument? - Complex skill memories involve the integration of motor patterns in the basal nuclei, cerebral cortex and cerebellum. Hippocampus Damage: How does hippocampal damage specifically impact memory, and are there ways to compensate for this loss? - If there is damage to the hippocampus it leads to an inability to consolidate memories. This means that it can’t convert short-term memories into long-term memories, however the long-term memories you already have remain intact. Some ways to compensate for this loss is cognitive rehabilitation, technology based interventions, and lifestyle modifications. Learning Mechanisms: How do neurotransmitter release, synaptic facilitation, and synaptic connections collectively contribute to learning? - Neurotransmitter release: the more released when learning something , the greater the effect on the postsynaptic neuron  - Synaptic facilitation: small quantities of neurotransmitter continuously released causing the postsynaptic neuron to be closer to threshold - Synaptic connections: branches from the axon form additional synapse on the postsynaptic neuron Brain Areas: What roles do the hippocampus and cortex play in learning and memory, and how do they interact? - The cortex and hippocampus are the main regions responsible for learning and memory. The hippocampus is responsible for forming new memories from integrating information from the different parts of the cortex. The cortex then stores these memories long-term. Hippocampus acts as a temporary storage for memory where the cortex is where long-term memories are stored once processed. Tertiary Memory: Why are tertiary memories considered more resilient, and what processes ensure their retention over a lifetime? - Tertiary memories are more resilient because the memory has to go through short-term first and then it gets moved into long-term secondary memory and then it moves into tertiary storage. Tertiary memories are normally with you for a lifetime unless there is a pathology that affects this area of memory. LTP Mechanisms: How does calcium signaling enhance synaptic strength, and what implications does this have for memory storage? 1. Ca++ triggers increase in number of glutamate receptors 2. Ca++ causes those receptors to stay open and active longer 3. Ca++ changes how readily the electrical wave spreads 4. Once Ca++ rushes in, it causes the synthesis of a retrograde neurotransmitter which increases the amount of glutamate being synthesized in the presynaptic neuron - This enhances synaptic strength because the calcium acts as a second messenger that triggers a cascade of biochemical events leading to the structural and functional changes at the synapse. The influx of calcium initiates a process that strengthens the connection between the neuron and its target neurons which help with consolidation of memories. LTP Disruption: How do factors like stress and alcohol interfere with long-term potentiation, and what are the consequences for memory? - Stress hormones released can enhance short-term memory but chronic stress that lasts for longer than 2 hours can disrupt LTP. Alcohol is another thing that interferes with memory and disrupts LTP. REM Inhibition: Why are somatic motor neurons inhibited during REM sleep, and how does this affect dream experiences?  - Somatic motor neurons are inhibited to prevent us acting out our dreams. Our neurons in our eye muscle are not inhibited which causes rapid eye movement in our REM sleep cycles. Consciousness in Sleep: What defines the levels of consciousness during sleep, and how does brain activity vary across sleep stages? - Our patterns of our brain waves define the levels of consciousness during sleep. These wave patterns can be seen using an EEG. Deep Sleep: How does deep sleep differ from REM sleep in terms of brain activity and responsiveness to stimuli? - Deep sleep (slow wave or non-REM) - Entire body relaxed and cerebral cortex activity is at a minimum - Heart rate, blood pressure, respiratory rate, and energy use declined by up to 30% - Rapid Eye Movement (REM) sleep - Actively dreaming - Blood pressure and respiratory rate change - Less receptive to outside stimuli - Muscle tone decrease - Inhibition of somatic motor neurons probably prevents acting out dreams (neurons of the eye muscles are not inhibited thus the rapid eye movement) Endocrine System System Differences: How do the nervous and endocrine systems complement each other in regulating body functions? The endocrine system and nervous system both work together to coordinate and regulate other cells, tissues, organs, and systems, and maintain homeostasis. The nervous system is more focused on communication and coordination between cells while the endocrine system regulates bodily processes. Hormone Effects: Why do hormones have tissue-specific effects, and what mechanisms ensure this specificity? Hormones have tissue-specific effects because they flow through the entire body through the bloodstream. Hormone receptors located on cell membranes or cytoplasm of cells ensure that only the correct hormone binds to the receptor rather than all the hormones that pass through the bloodstream. Peptide Hormones: How do peptide hormones differ from other types of hormones in structure and function? Peptide hormones are the largest class of hormones that are made up of chains of amino acids or small proteins. These hormones are water soluble, allowing them to circulate freely in the bloodstream without the need for carrier proteins. Hormones: How are various hormones released into circulation? Where do these hormones come from? What circumstances cause their release or inhibition? Anterior Lobe of Pituitary Glad Hormones: - Thyroid-stimulating hormone (TSH) - Targets the thyroid gland - Released due to increase in thyrotropin-releasing hormone (TRH) from the hypothalamus - Increased concentration of thyroid hormones inhibits release of TRH and TSH\ - Adrenocorticotropic Hormone (ACTH) - Stimulates release of glucocorticoids - Released due to an increase in corticotropin-releasing hormone (CRH) from hypothalamus - Increased concentration of glucocorticoids inhibits release of CRH and ACTH - Gonadotropins - Regulate activity of gonads - Occurs due to increase in gonadotropin-releasing hormone (GnRH) from hypothalamus - Follicle-stimulating hormone (FSH) - Stimulates development of follicles in ovaries (females) - Stimulates secretion of estrogen by ovarian cells (females) - Stimulates maturation of sperm cells (male) - Luteinizing hormone (LH) - Induces ovulation (female) - Promotes secretion of estrogen and progesterone (ovaries) (female) - Stimulates production of androgens (testes) (males) - Prolactin (PRL) - Stimulates mammary gland development - Stimulates milk production - May help regulate androgen production in males by increasing receptor sensitivity to LH - Growth hormone (GH) - Stimulates cell growth and replication - Most tissues have receptors - Skeletal muscle and chondrocytes are particularly sensitive - Increase stem cell division and differentiation in epithelia and connective tissue - Increase breakdown of stored triglycerides in fat cells - Increase breakdown of glycogen in liver (diabetogenic effect)  - Melanocyte-stimulating Hormone (MSH) - Increases melatonin production Posterior Lobe of Pituitary Hormone - Antidiuretic hormone (ADH) - Released due to rise in solute concentrations - Decreases water loss from kidneys (increases water reabsorption in kidneys) - Causes vasoconstriction (increases blood pressure) - Release is inhibited by alcohol - Oxytocin (OT) - Levels rise during sexual arousal and orgasm in both males and females - Stimulates smooth muscle contraction in uterus (females) - Onset of normal labor probably due to sudden rise in OT (females) - Stimulates “let down: of milk from mammary glands (females) - Stimulates smooth muscle contractions in the ductus deferens and prostate before ejaculation (males) Thyroid Gland Hormones - Functions: - Affect almost every cell in the body - Increase mitochondrial ATP production and cellular metabolism - In children, essential for normal skeletal, muscular, and nervous system development - Calcitonin: - Decreases Ca2+ concentrations in body fluids - Inhibits osteoclasts and stimulates Ca2+ excretion - Important in bone growth and decreasing bone loss (starvation and pregnancy) Adrenal Cortex Hormones - Aldosterone - Causes retention of Na+ (at the kidneys, sweat glands, salivary glands, and pancreas) and elimination of K+ - Secondary effect is the reabsorption of water in all of the above - Increase desire for salty foods - Secretion occurs due to drop in Na+ or increase in K+ levels in blood or decrease in blood volume or decrease in blood pressure - Glucocorticoids - Release stimulated by ACTH - Cortisol and corticosterone - Increased levels inhibit release of both ACTH and CRH  - Both accelerate the rate of glucose synthesis, and realsease of fatty acids, which increases glucose sparing metabolism - Hvae anti-inflammatory effects (steroid cream) - Androgens - Primary site for androgen release in females - Promote muscle mass, blood cell formation and support libido in females - Stimulate development of pubic hair in boys and girls before puberty Adrenal Medulla Hormones - Epinephrine and Norepinephrine - Skeletal muscle - Mobilization of glycogen reserves and acceleration of glucose breakdown - Increases both muscular strength and endurance - Adipose tissue - Stored fat broken into fatty acids for use in energy production - Liver - Break down of glycogen to glucose - Heart - Increase rate and force of cardiac muscle contraction (increases cardiac output) Adipose Tissue as Endocrine Tissue Hormones - Leptin - Bind to neurons in hypothalamus - Released during and after a meal - Causes sense of satisfaction and suppresses appetite - Must be present if GnRH and gonadotropin synthesis are to occur - Resistin - Reduces insulin sensitivity throughout the body - May be a link between type II diabetes and obesity Testosterone (Guest Lecture)