Exam 1 physiology
Visceral Nervous system (autonomic nervous system)
-involuntary -Automatically controls smooth and cardiac muscles and glands -Further divided into the sympathetic and parasympathetic nervous systems
steps of action potential generation
1. depolarization- Na+ rushes in and voltage becomes positive 2. repolarization- K+ ions leave cell. voltage becomes less positive 3. hyperpolarization- inside membrane becomes more negative as a rebound effect of extra K+ leaving. Sodium activation gate closes and inactivation gate opens 4. Na/K ATPase pump activated and pumps K back in, Na out to get back to resting *Note: step 1 occurs when threshold potential is reached
How does vitamin D become active?
1. hydroxylation in liver to 25-OH 2. second hydroxylation in kidney to 1,25-OH *1,25-OH is active form. increases GI calcium absorption
muscle contraction steps
1. nerve impulse at symaptic jxn 2. ACh release 3. ACh binds to muscle receptors and Na+ floods in 4. action potential in sarcolemma 5. a.p. travels down t. tubules 6. SR releases Calcium 7. Calcium binds troponin and reveals active site 8. myosin binds active site and power stroke occurs 9. myosin releases ADP and Pi 10. ATP attaches to myosin head and it releases from site 11. ATP cleaved and head recocks
steps of synaptic transmission
1. transmitter synthesis 2. transmitter storage 3. transmitter release from end terminal 4. receptor binding 5. termination of transmission *autoreceptor binding inhibits additional release into synaptic cleft
Net reaction of urea cycle. What is the main waste product in urine?
2NH3+CO2= urea+ H20. nitrogen is converted into urea for disposal in urine
The results of Meiosis are
4 unique haploid daughter cells
Percentages of fluids in body (body comp)
5% plasma 15% interstitial fluid 40% intracellular fluid
What is a motor unit?
A motor neuron and all of the muscle fibers it innervates
Serotonin
Affects mood, hunger, sleep, and arousal. only in CNS
Gliosis
CNS scar formation
diseases caused by destruction of myelin
CNS- Multiple sclerosis PNS- Guillain Barre
Periosteum
Covers outside surface of bone. inner layer is osteogenic because it has many osteoprogenitor cells
Oligodendrocytes
Form myelin sheath in CNS. can myelinate multiple axons
steps of somatic cell division
G0- normal state G1- cell growht, protein and lipid production S- DNA synthesis G2- continued growth M- cell division into 2 identical diploid cells
amino acid neurotransmitters
GABA
what type of bonds hold the two opposite strands of DNA together?
Hydrogen bonds
what are the main anions and cations of ECF? ICF?
ICF- potassium and phosphate ECF- sodium and chloride
Dopamine
In CNS. Reward behaviors
LDOPA can be changed into what other neurotransmitters?
LDOPA > dopamine > norepi > epi
Calcitonin
Lowers blood calcium levels. secreted by C cells of thyroid. inhibits ca absorption from GI, inhibits osteoclasts, inhibits kidney reabsorption
cholinergic receptors
Muscarinic- stimulated by muscarine. blocked by atropine Nictonic- stim by nicotine
appocrine glands
Open into hair follicles. respond to stress signals. secrete fatty acids. abundant in axillae and groin
sarcoplasmic reticulum
Organelle of the muscle fiber that stores and releases calcium.
Acetylcholine
PNS- motor neurotransmitter. inhibitory in cardiac tissue CNS- activates cholinergic system (sleep and memory)
Functions of the skin
Protection, absorption, sensation, temp, excretion
Bone marrow types and locations
Red marrow-produces red blood cells, in adults located in: ribs, vertebrae, pelvis, humurus, and femur Yellow marrow- adipose tissue (fat)- located in medullary cavity in adults
parasympathetic nervous system
Rest and digest. Storage of energy. Lowers HR, increases GI fxn, constricts pupils and bronchioles. Doesn't regulate sweating or arteriole tone
What is primary muscular fuel during rest? During strenuous activity?
Rest- fatty acids activity- glucose
What organelle is responsible for secreted protein synthesis?
Rough Endoplasmic reticulum
1 Motor neuron innervates many myocytes
That's it
Microglia
Type of phagocyte. Clean up after tissue injury. Derived from bone marrow.
Sarcomere Elements
Z disks M line thin and thick filaments
monoamine neurotransmitters
acetylcholine, serotonin, histamine
afferent vs efferent signals
afferent- towards CNS efferent- away from CNS
Epinephrine
aka adrenaline. fight or flight response
Catacholamine Receptors
alpha- vasoconstriction beta- bronchiolar dilation and increased heart rate
Hair growth cycle
anagen, catagen, telogen
Macroglia types (3)
astrocytes, ependymal, oligodendrocytes
What is axonal conduction affected by?
axon diameter and myelination
troponin equivalent in smooth muscle is?
calmodulin
creatine phosphate (CP)
can replenish muscular ATP for short periods. Donates Pi to ADP via creatine kinase. This is done during high intensity aerobic activity.
2 methods of synaptic transmission
chemical (most common) electrical
Astrocytes
connecting capillaries and neurons. transport nutrients and remove toxins contral uptake of water soluble molecules through BBB repair and scar formation in CNS
Slow fibers (red fibers)
contain lots of mitochondria and myoglobin. Oxidative and prefer fat as energy source.
tetanic contraction
continuous, forceful muscular contraction without relaxation
5 layers of epidermis
corneum, lucidum, granulosum, spinosum, basale (germitivum)
Where does glycolysis occur?
cytoplasm
Nocireceptors
detect pain. terminate in papillary dermis and around hair follicles. signals can be enhanced by prostaglandins, kinin, and substance P
Catecholamines
dopamine, norepinephrine, epinephrine
Roles of merkel cells
establish synaptic contacts with afferent sensory neurons receptors for light touch in sensitive areas of skin
sympathetic nervous system
fight or flight. increases HR, BP, and blood glucose. diverts blood flow from GI to brain. Dilates pupils and bronchioles.
small ratio of myocytes to neurons
fine motor control, low strength
Cartilage tissue. 3 types
firm, flexible connective tissue. avascular. formed by chondrocytes 1. elastic 2. hyaline 3. fibrous
smooth muscle
fusiform cells. 1 nucleus/cell. involuntary. line hollow organs. slow wavelike contractions
primary fuel of nervous tissue
glucose. Ketones can be used after metabolic adaption
roles of langerhan cells (dendritic cells)
help immune system recognize antigens contact hypersensitivity rxns wound healing, blood clots, inflammation
Norepinephrine
helps control alertness and arousal. in both PNS and CNS
large ratio of myocytes to neurons
high strength, low control
hypothalamus function
homeostasis (thermoregulation, thirst, hunger, etc)
effects of hypertonic or hypotonic solutions on RBCs?
hypertonic- shrunken hypotonic- swollen
Causes of nail clubbing
hypoxia
parathyroid hormone
increases blood calcium levels. increases osteoclast activity, enhances calcium reabsorption and vitamin D activation in kidneys
Factors affecting bone growth
injury to epiphyseal plate, mechanical stress, nutritional status, hormones
Where does oxidative phosphorylation occur?
inner mitochondrial membrane
what charges does a resting cell have intracellulary and extracellularly?
intra- negative extra- positive
Fasiculations
involuntary twitching of muscle fibers
Cori Cycle
lactate > pyruvate > glucose
lamellar vs woven bone
lamellar- mature bone that is layered woven- immature bone that has random matrix structure
3 types of hair
lanugo, vellus, terminal
Meissner's corpuscles
light touch/pressure. located in papillary dermis
Osteocytes
located in lacunae. Sense bone stress strain. coordinate blasts and clasts
Endosteum
membranous lining of the hollow cavity of the bone
Where does the Krebs cycle occur?
mitochondrial matrix
isotonic contraction
muscles contract and shorten (movement)
isometric contraction
no shortening; muscle tension increases but does not work (no movement)
sebacious glands
oil glands. Cover entire skin surface except palms and soles of feet
Histamine as a Neurotransmitter
only in CNS. responsible for arousal, thirst, BP.
What does the Golgi body do?
packaging and transport of proteins, glycosylation
colicky pain
pain caused by spasm of the smooth muscle; occurs when a muscular wall of a hollow tube attempts to force certain contents of the tube out of it
Transverse tubules (T-tubules)
path for action potential from motor neuron synapse to sarcolemma then to Sarcoplasmic reticulum
Sarcolemma
plasma membrane of a muscle fiber
Which structures are responsible for life support reflexes?
pons and medulla
ependymal cells
produce cerebrospinal fluid
eccrine glands
produce sweat. originate in dermis. abundant on palms, soles of feet, forehead, and axilla. Open directly onto skin surface
Functions of the skeletal system
protection, positioning, framework, stability, shape, storage of calcium and phosphate, hematopoietic
fast muscle fibers (white muscle, type 2B)
quick, strong contraction. Anaerobic respiration, glycolysis, high glycogen fine, rapid, precise movement sprints quick fatigue, produce lactate
mast cells
release histamine
Pacinian corpuscles
respond to deep pressure and vibration. located in reticular dermis
which layer of the dermis is responsible for langers lines
reticular dermis
rufinis corpuscle
sense distortion or stretching. located in reticular dermis
what factors contribute to osmolarity calculation?
sodium, glucose, BUN
Types of bone tissue
spongy- have red marrow. lattice like pattern formed of trabeculae. compact- rigid, laminar, densely packed calcium matrix
rigor mortis
stiffness in body post mortum caused because no more ATP production. Cross bridges become locked in place
which epidermal layer goes through mitosis?
stratum basale
Which epidermal layer is only found in thick skin?
stratum lucidum
cardiac muscle
striated, branched, intercolated discs. involuntary. prefer fat for energy
Blood vessels in dermis
subpapillary- jxn of papillary and reticular dermis. perfuses the dermal papillae cutaneous- dermal, subcutaneous interface. larger blood vessels lymphatic- helps w immune defense
2 parts of autonomic nervous system
sympathetic and parasympathetic
tendons and ligaments
tendons (muscle to bone) and ligaments (bone to bone)
saltatory conduction
the jumping of action potentials from node to node
What is beta oxidation and where does it occur?
the process of converting fatty acids into acetyl-coA for transport into mitochondria. Fatty acids carried by fatty acyl carnitine
thin filaments vs thick filaments
thin- actin, tropomyosin, troponin thick- myosin
types of intercellular junctions (4)
tight, desmosomes, gap, hemidesmisomes
2 types of slow muscle fibers
type 1- slow oxidative- postural muscles. very fatigue resistant, efficient contraction type 2- fast oxidative- action muscles. moderately fast contraction and fatigue resistance
What causes gout?
uric acid- a waste product of nucleotide degradation
types of ion channels
voltage gated, ligand gated, passive, mechanical/light gated
Under what conditions does ketogenesis occur?
when fat is being metabolized too quickly. In fasting conditions
What organelle is responsible for steroid synthesis?
Smooth Endoplasmic reticulum
In which epidermal layer does keratin production start?
Spinosum
In which epidermal layer are melanocytes found?
basale
Where are blisters formed?
basement membrane
Osteoblasts
bone forming cells. secrete alkaline phosphatase= calcification.
osteoclasts
bone removing cells. Release H+ which dissolves calcium hydroxyapatite Release hydrolytic enzymes and proteases
osteoprogenitor cells
bone stem cells. located in periosteum, endosteum, epiphyseal plate. Become osteoblasts