Anatomy and Physiology EXAM1 Flashcards
define anatomy
the study of the structures & the shape of the body and its parts
define physiology
the study of how the body and its parts work or function
define organ
a structure composed of 2+ tissue types that perform a specific function
define the integumentary system
the external covering of the body, or the skin, including the hair and fingernails
define the skeletal system
bones, cartilage, and joints. support the body and provides framework
define the muscular system
formed of skeletal muscles that contract to lead to movement
define nervous system
fast acting control consisting of the spinal cord, brain, nerves, and sensory receptors
name and use directional referencing terms
superior: top
inferior: bottom
anterior/dorsal: front
posterior/ventral: back
lateral: outside
medial: middle
define the different cuts of a brain, as an example
sagittal: divide right and left hemispheres
coronal/frontal: divide into front and back
define homeostasis
the maintenance of relatively stable, or optimal, conditions in the body in response to changes
Is sweating a negative or positive feedback loop?
negative, it has the net effect of trying to reduce the heat of the body
what is an example of a positive feedback loop?
childbirth, the mother cannot stop “having the baby” after the process of birth has started
Know the terms receptor, control center, and effector
Receptor: recieves info
Control center: makes decisions
effector: responds based on control center
define the process of Ingestion using
mastication and deglutition
Ingestion: the taking in/eating of food
Mastication(chewed)
Deglutition (swallowing)
describe digestion and the two types of it that occur in the body
Digestion is th breaking down of food for digestion. It involves peristalsis (wave-like contraction that propels food through the digestive system.)
2 types:
Mechanical digestion: physically breaking up food
Chemical digestion
define Propulsion
food is moved through the digestive system using muscular contractions
name the organs of the alimentary canal and accessory digestive organs, and identify each on a diagram or model
alimentary canal is another name for the digestive system
- Mouth (salivary glands; creates bolus)
- Esophagus (2 sphincters at top and bottom; smooth) muscle)
- Stomach (thick musclualris layer as it has 3 layers for protection; acidic; mechanical digestion)
- Small intestine (villi and circular fold increase SA for absorption; chemical digestion)
- Large intestine (smooth; voluntary and involuntary sphincters; water absorption; fecal formation)
- Rectum
- don’t forget accessory organs!
what are the accessory organs and their functions?
- Pancreas (endocrine and exocrine gland; produces juices and brush border enzymes that dump into the duodenum to help digest food)
- Liver (processing, storing, detoxification of food)
- Gall Bladder (hols bile produced by the liver and pumps into the duodenum)
- Appendix (store gut bacteria)
describe the 4 layers comprising the GI tract.
Lumen (innermost layer)
*Mucosa (mucus membrane)
*Submucosa (has blood, lymphatic vessels, and nerves)
*Muscularis (smooth muscle moves food through system)
*Serosa (connective tissue)
explain the four unique qualities of muscle tissue and why they are important
Contractility (ability to shorten when stimulated)
Excitability (responsiveness to stimulus)
Extensibility (ability to be stretched)
Elasticity (ability to recoil after being stretched)
describe the three different muscle types in humans and explain their differences
- Smooth muscle (in digestive tract; involved in opening and closing eyes; slower; uninucleated)
- Cardiac muscle (found only in the heart; striated; specialized; repeated, rhythmic contractions; involuntary)
- Skeletal muscle (attached to bones; long, striated; voluntary; widespread; makes up a lot of body weight; faster to slower; maintain posture, generates heat, and stabilizes)
Describe and be able to label the anatomy of skeletal muscle (including fascicles, muscle cells, myofibrils, epimysium, endomysium, and perimysium)
Deep to superficial:
Sarcomere
Myofibril
Muscle fiber
Fsacicle
Endomysium (surrounds fascicle)
Parimysium (binds fascicles together)
Epimysium (binds everything to form a tendon)
Tendon attaches to bone
Describe how excitation and contraction coupling works at the NMJ
ACh Release: Action potential in neuron triggers ACh release
ACh Binding: ACh binds to receptors on muscle fiber.
Action Potential: Triggers muscle cell action potential.
Calcium Release: Action potential causes calcium release by binding to troponin, which removes tropomyosin
Myosin heads binds with use of ATP
Titin holds tension
Muscle Contraction: Calcium initiates muscle contraction.
AChE: clears ACh from synapse
Muscle Relaxation: End of nerve signal leads to muscle relaxation.
describe the process of muscle contraction (cross-bridge cycling)– including the actions of thick filaments (myosin), thin filaments (actin) and how they interact
Signal Initiation: Nerve impulse triggers action potential.
Calcium Release: Action potential opens calcium channels in muscle cell.
Thin Filament Activation: Calcium binds to troponin, exposing binding sites on thin filaments (actin).
Cross-Bridge Formation: Myosin heads (thick filaments) bind to actin (thin filaments).
Power Stroke: Myosin heads pivot, pulling thin filaments towards the center.
Release and Reset: ATP binds to myosin, detaching it from actin, and resetting the myosin head.
Repetition: The process repeats, causing sliding of filaments and muscle contraction.
define label the anatomy of a muscle cell and be able to identify it
Sarcolemma: Cell membrane of muscle cell.
Sarcoplasm: Cytoplasm containing organelles.
Myofibrils: Thread-like structures for contraction.
Sarcoplasmic Reticulum (SR): Stores and releases calcium.
T-Tubules: Transmit nerve signals for contraction
Explain how strength is determined of muscle contractions, with a specific understanding of the terms tetanus and recruitment
Control strength of contraction by increasing the frequency of signals (tetanus) or by increasing the number of motor units that are recruited for a single contraction
- Graded muscle responses: variation in muscle tension that results from a variable demand
define tetanus
Prolonged, continuous muscle contraction without relaxation due to rapid and repetitive stimulation.
explain the cause of muscle fatigue
Muscle fatigue: can no longer generate or sustain an expected power output even if stimulated
Unknown cause. Some ideas are an ionic imbalance, NMJ problems, running out of ATP, or lactic acid buildup.
what role does EPOC (post-exercise oxygen consumption) have in restoring energy balance?
EPOC: increase in oxygen consumption to replenish PCr and oxidize lactic acid. this leads to regeneration of pyruvate and the replenish of glycogen store in the liver
- influenced by exercise intensity, age, gender, etc.
- tends to last 15 min to 45 post exercise
define what a myelinated neuron is and explain how myelination affects the transmission of an action potential
Myelinated neuron: a protective sheath called myelin around nerve fibers (axons) in the nervous system.
is composed of lipids (fats)
acts as an insulator and enhances the speed and efficiency of nerve impulses
helps neurons transmit signals more quickly and with less energy expenditure.
explain the concept of a threshold stimulus and the three phases of an action potential
- Depolarization: Membrane becomes positive. Na+ flows in
- Repolarization: Returns to resting state. Na+ gate closes, K+ finally opens and lets out K+
- Hyperpolarization: Briefly more negative than resting state.
*Return to resting potential (-70) until threshold (-55) is reached again
describe how an action potential is propagated down an axon
Depolarization: Stimulus opens sodium channels, causing a positive charge.
Propagation: Action potential jumps (saltatory) or travels continuously.
Repolarization: Sodium channels close, potassium channels open, restoring negativity.
Continuation: Process repeats along axon until reaching terminals for neurotransmitter release.
explain how voltage-gated channels operate during an action potential.
Sodium Channels (Na+):
- Open: During depolarization (rising phase).
- Close: Shortly after opening (inactivation) and remain closed during repolarization.
Potassium Channels (K+):
- Open: During repolarization (falling phase).
- Close: Once the membrane potential returns to its resting state.
describe the CNS vs the PNS
CNS: brain and spinal cord
PNS: all neurons sending signals to and from the body
describe a membrane potential, how it is maintained, and why it is important.
Membrane Potential: Voltage difference across a cell’s membrane.
Maintenance: Achieved through selective ion permeability, ion pumps, and leak channels.
Importance:
Essential for nerve and muscle function
Drives cell signaling (action potentials)
Maintains ion balance
describe the anatomy and functional significance of peripheral nervous system neurons, including the terms nerves and ganglion
PNS: all neurons outside the brain and spinal cord. transmit sensory information to the CNS and relay motor commands from the CNS to muscles and glands, enabling long-distance communication
Nerves: bundles of neuron fibers
ganglia: clusters of nerve cell bodies.
describe the general anatomy of a neuron
Cell Body: Contains the nucleus and organelles.
Dendrites: Branch-like extensions that receive signals.
Axon: Long fiber that transmits signals.
Axon Terminal: End of axon, releases neurotransmitters.
name the Three General Types of Neurons
- Sensory Neurons: Transmit sensory information from receptors to the CNS.
- Interneurons: Process and relay signals within the spinal cord of the CNS.
- Motor Neurons: Carry signals from the CNS to effectors like muscles or glands.
describe the signaling path through the peripheral nervous system.
Sensory Receptors detect stimuli.
Sensory Neurons Transmit signals to the CNS.
CNS interneuron processes information
Motor Neurons send signals to effectors
muscles/glands respond
describe how the type of muscle fiber creates physiological limits on muscle performance
Muscle Fiber Type: The distribution of fast-twitch and slow-twitch muscle fibers in an individual’s muscles can set limits on endurance and strength.
- Slow-twitch fibers= endurance
- Fast-twitch fibers= strength training; powerful but fatigue quickly.
what is the advantage of having gut microbes? how do you promote the microbiome?
Advantage: breaks down food that the body cannot and protects against germs
- promote by healthy, high fiber diet with probiotics (yogurt)
describe simple columnar epithelium tissue
- found in the stomach and intestines
- facilitates absorption and secretion of nutrients
(pink columns)
describe stratified squamous epithelium tissue
- lines esophagus, mouth, and high abrasion areas
- protects tissues
(pink; very dense and dotted)
describe areolar connective tissue
- connects and supports organs
- found everywhere and is flexible
(pink and streaked, like hairs)
describe smooth muscle tissue
- movement and valves
- peristalsis (food movement)
(pink and smooth)
describe the general hierarchical structure from a muscle cell to a tendon
one muscle cell
muscle fiber
myofibril
fascicle
bundle of muscle fibers
muscle
tendon (connects muscle to bone)
what are skeletal muscles responsible for? what are 3 common characteristics of them?
- producing movement
- stabilizing body position
- producing heat
- elongated, multinucleated, straited
what connective tissue is part of a skeletal muscle ( deep to superficial) ?
Endomysium: Innermost connective tissue layer, surrounds individual muscle fibers.
Perimysium: Middle layer, encases bundles of muscle fibers (fascicles).
Epimysium: Outermost layer, envelops the entire muscle and connects it to tendons.
What is the correct muscle terminology that corresponds to these general terms?
muscle cell
cell membrane
cytoplasm
modified endoplasmic reticulum
muscle cell - muscle fiber
cell membrane - sarcolemma
cytoplasm - sarcoplasm
modified endoplasmic reticulum - sarcoplasmic reticulum
define a myofibril
structure in muscle cells responsible for muscle contraction
- composed of actin and myosin proteins
- organized into repeating units called sarcomeres.
how did the animation shown in class of the muscle fiber misrepresent cross-bridge cycling?
the video shows the sliding happening simultaneously, which is wrong.
**cross-bridge cycling happens asynchronously, where some myosin heads are bound while others are released, to hold tension
define hypertrophy
muscles get bigger when fibers become thicker (from added myofibrils), which adds more nuclei for increased protein synthesis
define afferent vs efferent
afferent: signals delivered to CNS
efferent: signals delivered away from CNS
define neuron and neuroglia
Neuron: Nerve cell transmitting signals.
Neuroglia (Glia): Supportive cells in the nervous system.
what are the 3 properties of all neurons?
- excitable (receive signals)
- conductive (send signals)
- secretory (release NT to send signals)
what does the acronym SAME DAVE mean?
(sensory-afferent, motor-efferent; dorsal-afferent, ventral-efferent)
what is a ganglion? what is it called in the CNS?
ganglion: collection of neuronal cell bodies in the PNS
- in the CNS: called “nuclei”
what is the toxin that prevents action potentials?
tetrodotoxin; found in fugu sushi. blocks NS cell signaling and can lead to flaccid paralysis
which voltage gates are slow and which are fast?
slow: Na+ inactivation and K+ activation
fast: Na+ activation
