Homeostasis Flashcards
Hypothalamus
Region of brain that releases hormones to control pituitary gland which controls other endocrine glands
Neurohormone
Hormone made by neutrons such as in hypothalamus that control production of other hormones in the pituitary
Pituitary gland
Two loved gland in cranial cavity that makes hormones that control other endocrine glands
Thyroid gland
Endocrine gland in throats that is regulated by the hypothalamus pituitary system
Parathyroid hormone
Hormone secreted by parathyroid that controls levels of calcium and phosphate in the blood
Pineal gland
Endocrine gland located in brain of vertebrates that secretes hormone melatonin to regulate biological rhythms
Islets of langerhans
Endocrine cell clusters inside pancreas that produce insulin and glucagon
Synthetic hormone
Hormone made by humans that acts as a natural hormone
Gonads
Glands responsible for production of sex hormones as well as egg and sperm cells. Called testes and ovaries
Oogenesis
Production of eggs or ova from oocytes in ovaries by two meuotic divisions
Gonadtropin releasing hormone GnRH
Hormone released by hypothalamus that controls release of LH and FSH from anterior patuitary which controls synthesis and release of male and female sex hormones
Menopause
End of females reproductive capability when menstruation ceases and female hormone level drops
Menstrual cycle
Monthly cycle of events in sexually mature female that prepares the uterus for the implantation of a fertilized egg
Spermatogenesis
Production and development of sperm cells in the testes
Osmoregulation
Process of actively regulation the osmotic pressure of bodily fluids and cells
Osmotic pressure
Pressure that results from a difference in solute concentration between two sides of a selectively permeable membrane
Hyperosmotic
Property of the solution that has the lower water concentration
Hypoosmotic
Property of solution was on one side that has the higher water concentration
What way does water move over a membrane
Goes to hyperosmotic side
Estivation
State of tupor that enables an animal to survive the summer by reducing demand for energy
Malphigian tube
Main organ of excretion in insects which is used to carry waste to the intestines
Nephron
Tiny functional unit of kidney that filters waste from blood
Protein hormone
Hormone made of chains of amino acids that are water soluble usually acts on a cell receptor
Steroid hormone
Hormone made of cholesterol that isn’t water soluble. Usually goes thru cell membrane and acts on receptor inside
Glucagon
Hormone made by alpha beta cells in pancreas that increases blood glucose level by promoting breakdown of glycogen in liver
Thermoregulation
Regulation of internal temp by negative feedback mechanism
Homeotherm
Animal that maintains stable body temp regardless of external temp
Poikilotherm
Animal whose body temp varies and matches temp of external temp
Endotherm
Animal that maintains body temp by internal mechanisms
Ecotherm
Animal that maintains its body temp by absorbing thermal energy from the environment
Thermal acclimazation
Process by which an animal gradually adjusts to temp change in the environment
Torpor
Short term state of reduced metabolism and body temp that reduces the E demand for an animal in the night or day
Interstitial fluid
fluid that surrounds body cells
Negative Feedback
process where a mechanism is activated to maintain equilibrium, so if too much of something is being made it will go back and tell it to slow down production, to maintain equilibrium
Negative Feedback Example
Regulating blood sugar. So as glucose levels rise insulin is produced then as glucose levels decrease less glucose is made.
Negative feedback temperature example
high body temp. Hypothalmus turns on cooling system, blood vessels dilate and heat is lost through skin. Temperature lowers and hypothalmus turns off cooling system.
excititary drugs
coke, amphetamines, nicotine
inhibitory drugs
benzos, alcohol, marijuana
Parts of Forebrain
olfactory, cerebrum, corpus callosum, thalamus, hypothalmus
Midbrain section and role
4 spheres of grey matter, and is the relay centre for eye and ear reflexes.
Olfactory Lobe
Recieve smell info
Cerebrum description
most developed and largest regions of the brain. Stores sensory info and initiates voluntary motor activities
Parts of cerebrum
frontal, parietal, temporal, occipital
Frontal lobe
in cerebrum. linked to intellectual areas and personality. Primary motor cortex
Parietal Lobe
sensory areas of touch and temp. emotions. speech. in cerebrum
Temporal Lobe
vision and hearing memory. cerebrum
occipital lobe
vision cerebrum
corpus callosum
in forebrain. nerve tract that joins two cerebral hemispheres
thalamus
coordinates and interprets sensory info and directs it into cerebrum
sensory pathway
spinal nerves-nerve tract in spinal cord-relay nerves i thalmus-cerebrum
hypothalmus
coordniation centre for autonomic nervous system. involved in hormone production.
Parts of hindbrain
cerebellum, pons, and medulla oblongata
cerebellum
gets input from all sensory areas and controls all motor control.
Pons
sends nerve messages between cerebellum and medulla
medulla oblongota
involuntary muscle action and coordinates ANS. nerve tracts from higher brain and spinal cord run thru medulla
Parts of outer layer of the eye
Sclera and Cornea
Sclera
Clear, front protective layer of the eye that helps maintain the shape.
Cornea
helps bend light towards the pupil. is the transparent part of sclera
Aqueous humour
transparent fluid that helps protect lens of eye, supply cornea with nutrients, refract light
Choroid
middle layer of eye. Contains blood vessels to protect against reflection
Iris
Diaphragm controlling pupil size
Vitreous Humour
Contains shape of eyeball. allows light transmission to retina
Lens
Focuses image on retina. located behind iris
Pupil
Hole in iris that lets light into eyes
Retina and its layers
Innermost tissue at back of eyes. Layers are Light sensitive, bipolar and cells from optic nerve
rods
photoreceptors operate in dim light to detect light in black and white
Cones
photoreceptors work in bright light to detect colours
Fovea Centralis
centre of retina. Contains cones condensed together. Rods surround fovea
Blind Spot
results from absence of rods and cones where optic nerve meets retina
Bloid Brain Barrier BBB
Tight control over what gets into the brain. very good protection against bacteria, so is hard for drugs that are targeting the brain to get through this sometimes
Dopamine
Feel good drug. Increased by various addictive drugs and increased by natural endorphin’s
Menses
Day 1-5 in menstrual cycle. When bleeding occurs
Follicular stage
day 5-14 in menstrual cycle. Light build up of uterine lining When follicle is developing. Egg bursts on day 14
Luteal phase
Day 15-28 in menstrual cycle. When the uterine lining builds up the most.
Two cycles within the menstrual cycle
ovarian cycle where egg development leading to ovulation. And uterine cycle which is the build up of the lining of the uterus.
Pinna
External ear flap. Selective funnel to collect sounds. Funnels sounds at 3 kHz
Auditory canal
Carries sound to ear drum. Makes ear wax
Middle ear
Extends from tympanic membrane to oval and round windows. It amplifies and carries sound to oval window
3 ossicles
Malleus incus and stapes
Amplification
Oval window smaller then tympanic membrane and bones act as a series of levers that transform low force waves into high force waves
Vestibules
Two small sacs that establish head position via static equilibrium
Semicircular canals
Arranged at 3 different angles. Movement of fluid in canals identified body movement and maintains balance
Cochlea
Inner canal has specialized hair cells. Depolarization of cells initiate nerve impulses that travel to temporal lobe and allow hearing
Neuron
Nerve cell capable of conducting nerve impulses and sending messages
Neural signalling
Reception transmission and integration of nerve impulses by neurons and the response to these impulses
Motor neuron
Neuron that carries impulses from cns to skeletal muscle. Aka motor neuron
Sensory neuron
Neuron that carries impulses from sensory receptors to cns
Interneuron
Local circuit neuron of cns that relays impulses between sensory and motor neurons
Dendrite
Protection of cytosol that carries signals toward nerve cell body.
Axon
Extension of cytosol that carries nerve signals away from the nerve cell body
Sensor
Elements of feedback system that detects changes in the environment
Integrator
Element of feedback system that compares existing conditions with ideal ones
Set point
Optimal variable for given variable of a system
Effector
Element of feedback system that acts to return the system to the optimal state
Positive feedback
Response of a system that acts to increase effect of any changes made to the system
Meninges
Three layers of connective tissue that surround and protect the brain and spinal cord
Cerebrospinal fluid
Circulating fluid that surrounds the membranes of the brain and spinal cord. Provides neural connection to the endocrine system
Grey matter
Tissue of the brain and spinal cord where the cell bodies and dendrites of neurons are located
White matter
Tissue of the brain and spinal cord composed primarily of axons of neurons. It surround grey matter in spinal cord
Homeostasis
Physiological state of body where internal physical and chemical conditions are kept wishing a range that is suitable for life. Things that are regulated are temp pH, blood glucose and water and dilute balance
Body systems involved in homeostasis
Nervous. Endocrine. Muscular. Integumentary. Excretory. Reproductive.
Diabetes mellitus
Lack of insulin. So excess sugar in tubule. Large urine volumes. Treat with insulin injections
Diabetes insipidus
Destruction of neurosecretory cells in hypothalamus or in nerve tract. Lack of ADH. Increased urine output. Treat with ADH shots
Bright’s disease
Bacterial toxins destroy vessels in glomerulous. Inflamed nephrons. Proteins in bow and capsule. Increased urination. Treat with antibiotics
Kidney stones
Mineral diluted from blood lodge in ureter and urethra. Painful and hurts soft tissue High energy shock waves treat it
Peritoneal dialysis
Catheter introduces dialysis fluid into abdominal cavity and drained every 6 hours.
Role of ADH
Cause membrane of collecting tubules to be more permeable to water to be reabsorbed so less urine is excreted.
Course of action of ADH
Signal sent to posterior pituitary. ADH released. Kidney tubules absorb more water. Osmotic pressure decreases and cells are hydrated. Nerve message sent to posterior pituitary and no more ADH released
Role of Aldosterone
Increased salt reabsorption in distal tubules and collecting ducts so increased water reabsorption
Action of aldosterone
Made in adrenal cortex. Targets kidney tubules. Control salt water balance by increasing Na+ reabsorption
ADH produced and stored
Made in hypothalamus and stored in posterior pituitary
Diuretics
Ex. Alcohol green tea. Decreases the release of ADH and therefore the tube is less permeable. So less water reabsorbed so lots of pee
Action of juxtaglomerular apparatus in regulating BP
Detects low BP. Renin released to convert angiotensinogen to angiotensin. Vasoconstriction to increase BP. Aldosterone increased for higher Na+ reabsorption. Helps maintain BP during stress
Fresh water fish
Actively transport water and salt back into body by kidney and gills. Highly diluted urine is excreted to get rid of excess water
Marine fish
Lose water through gills and salt is actively excreted. Small quantities of urine excreted.
Amphibian
Lose water by osmosis. Water reabsorbed by kidney to be stored for a reserve
Reptile
Converts nitrogenous waste to insoluble Uric acid which is excreted with little water loss
Bird
Concerts ammonia to insoluble uric acid which needs little water to be excreted so water can be excreted then absorbed. by kidneys
GnRH role in spermatogenesis
Secreted by hypothalamus ever two hours to stimulate pituitary gland to release FSH and LH
FSH role in spermatogenesis
Initiates sperm production at puberty maintains sperm production and growth of servility cell to nourish sperm.
What inhibits FSH production
Fertility cell secretions
LH role in spermatogenesis
Stimulates testosterone To be produced. Controls growth and function of male reproductive structure. Secretes sex hormones
What triggers ovulation
Rising LH decreasing FSH resulting from an increase in estrogen
Corpus cavernosum
Two masses of sponge like tissue made of smooth muscle and blood vessels. Extend to almost head of penis. Fills with blood during erection. Is 90% of blood
Corpus Spongiosum
Tissue that surrounds urethra and prevents it from being compressed. Without this the penis would pinch and nothing could get out
Prostate gland
Produced prostate fluid that protects sperm
Seminal vesicles
Fluid that gives energy to sperm to swim
Cowper’s glands
Make lubricating fluid and secretes it into urethra
Functions of testosterone
Maintains sex drive. Triggers and regulates secondary sexual characteristics. Initiates pre natal development of geneticists
Ovaries
Secrete estrogen and progesterone make ova
Oviducts
Transport ova to uterus
Uterus
Lining thickens in prep for baby
Cervix
Junction of uterus and vagina. Stretching occurs during menstruation and child birth
Vagina
Functions in childbirth and intercourse
Role of kidney in maintaining homeostasis
Decides how much water is kept in the body and how much is released as urine based on the other hormones being secreted. All blood in the body has to flow through here
Adrenaline
Fight or flight neurotransmitter. Leads to increased heart rate so you are physically more aware and your senses are heightened.
GABA
Calming neurotransmitter. High levels improve function but low levels increase anxiety
Acetylcholine
Transmit signal to skeletal muscle
Sympathetic nervous system
Part of ANS. fight or flight response preparing the body for stress
Parasympathetic nervous system
Part of ANS. restored body to normal relaxed state
Noradrenaline
Affects flight or fight. And affects concentration
Dopamine
Feel good drug neuroreceptor. Affects mood and sleep
Serotonin
Widespread in brain. Affects sleep mood attention and learning. Inhibitory
Endorphins
Neurotransmitter that works within the brain and is released during pleasuresable activities. Helps reduce feeling of pain during exercise block signal in the brain stem
Enkephalins
Peptides related to endorphins that have a similar effect block signal in spinal cord
Alzheimer’s
Reduced amounts of acetylcholine in hippocampus due to the degeneration of neurons. The memory loss occurs because acetylcholine is related to memory and learning.
Parkinson’s disease
The ganglia in the brain that makes dopamine dies off. And this causes not enough dopamine to be made which causes the shaking due to not enough dopamine there to send the message
Role of nervous system on homeostatic system
Received sensory data from environment which informs the body of external conditions and transmits signals throughout the body
Role of endocrine system on regulating nervous system
System of glands that produce and secrete hormones. These hormones are responsible for a number of things
Steps in formation of urine 10
Blood goes thru bowmans capsule. Only filtrate gets thru. No blood cells or proteins. Proximal tubules reabsorbs glucose and amino acids and k+. Active transport of Na+ out. Water reabsorbed at bottom of loop of Henle so more concentrated solution at bottom. Hormones decide how much water needs to eat reabsorbed. More sodium enters collecting tube and then urines excreted
Filtration
Blood cells platelets and plasma proteins are too big to go thru bowmans capsule so are filtered out. Water ions glucose and nitrogenous waste are small enough to fit thru so aren’t filtered out
Reabsorption
Active transports back into the interstitial fluid are glucose amino acid and other useful minerals. These are reabsorbed because it’s more efficient for the body to reuse them
Secretion
Different amounts of H+ and K+ are secreted into filtrate to balance acidity and to be excreted by urine
Efferent arteriole
Small branches that take blood away from glomerulus
Peritubular capiliaries
Blood vessels that surround the nephron
Proximal tubule
Section of nephron joining bowmans capsule to loop of Henle
Loop of Henle
Carries filtrate from proximal to distal tubule
Distal tubule
Conducts urine from loop of Henle to collecting duct
Collecting duct
Tube that carries urine from nephron to pelvis of kidney
Afterward arteriole
Supplies blood to nephron in kidneys
Distal convulated tubule
Duct to nephron that connects loop of henle to ducts that lead to renal pelvis
Proximal covulated tubule
Reabsorbs ions water nutrients and adjusts pH
Tubule and ADH
ADH makes it more permeable so more water can be reabsorbed. Maintains blood ph and electrolytes
Free non encapsulated efferent endings
Most common. In muscle and connective tissue
Krause corpuscles
Encapsulated ending. Simplest ends in oval bulb. Lips tongue
Meissner corpuscle
Detect complex tactile stimuli finger tip palm encapsulated
Pacinion corpuscle
Encapsulated. Detect deep heavy pressure
Muscle spindles.
Encapsulated. Regulate reflex action and muscle tone
Meninges
Protective membrane that surrounds brain and spinal cord
Layers of meninges
DAP
Dura mater
Arachnoid Mater
Pia mater
Cerebrospinal fluid
Circulated between inner and middle meninges. Shock absorber
TSH
Made in AP. targets thyroid. Stimulates secretion of thyroid hormones and growth of thyroid gland
ACTH
Made in AP targets adrenal cortex. Stimulates secretion of glucacarotoids by adrenal cortex.
GM somatropin
Bone soft tissue. Made in AP. stimulates growth of bones
FSH female
Made in ap. stimulates egg growth. Targets ovaries
LH in females
Targets ovaries. Made in AP. regulates ovulation
Prolactin.
Made in ap. targets mammary glands. Stimulates breast and milk production
Oxytocin
Stored in PP. targets uterus and mammary glands. Promotes uterus contraction. Stimulates milk release
ADH
Stored in PP. increase water reabsorption
Thyroxin
Stored in th. targets most cells and increases metabolic rate.
Calcitonin
Made in th. targets bones. Decrease calcium concentration in blood b
Insulin
Targets blood sugar. When increased blood sugar the insulin production is increased
Glucagon
Targets blood sugar. When low blood sugar glucagon production increases
Aldosterone
In AD. Targets kidney tubules increases sodium reabsorption.
Cortisol
Made in AC. Targets most body cells. Increased blood glucose by promoting breakdown of protein and fat
Epinephrin. Adrenalin
Made in AD. Targets receptor sites throughout body. Contributes to body’s response to stress
Inhibin
Made in testes. Inhibits secretion of FSH
Testosterone
Made in testes. Stimulates secondary sex characteristics
Estrogen
Induces growth of uterus and onset of menstrual cycle
Progesterone
Promotes development of endometrium
Retina to brain pathway
Rods/cones - bipolar cells - ganglion cells - optic nerve - thalamus - primary visual cortex - visual association cortex
Division of nervous system
Peripheral nervous system and central nervous system
Divisions of peripheral nervous system
Somatic and autonomic nervous system
Divisions of central neurons
Brain and spinal cord
Somatic nerves
Are voluntary. Sensory nerves and motor nerves
Autonomic nervous system
Involuntary. Parasympathetic and sympathetic
Anabolic steroid
Stanozolol it increases muscle strength and mass. Decreases growth. Causes kidney problems. Hair loss
Peptide hormones
Growth hormone. Decrease fat and increase muscle. Causes diabetes bone abnormalities increases blood pressure
Masking agents
Probenecid. Stops excretion of steroids for a few hours. Causes headaches and swelling nausea
Anabolic steroids
Mimic muscle building characteristics of testosterone
Acrosomal reactions
Contents of acrosome are released by separation of acrosomal cap from sperm. Proteases from acrosome digest route for spent through zona pellucida. Allows the sperm to reach the plasma membrane of egg
Cortical reactions
Small vesicles called cortical granules move to plasma membrane of egg and fuse it with releasing there contents by exocytosis. Enzymes cause cross linking of glycoproteins in the zona pellucida making it hard and prevents entry of any more sperm
Pathway of reflex arc
Stimulus causes action potential in sensory receptor. Message travels along sensory dendrite. Message travels along sensory axon. Message reaches interneuron dendrite. Message splits one to brain and one to motor neuron dendrite. Message travels along motor neuron axon. Message causes muscles to contract