Muscular, Skeletal, and Respiratory Systems Flashcards
function of skeletal muscle
- voluntary motion
location of skeletal muscle
- attached to the bones
nuclei of skeletal muscle
- multinucleated
microscopic appearance of skeletal muscle
- striated
hierarchy of muscle
- protein filaments - actin and myosin
- sarcomere
- myofibril - string of sarcomeres
+ organelles
+ cytosol
+ plasma membrane - muscle cell - bundle of myofibrils
- fascicle - bundle of muscle cells
- whole muscle - bundle of fascicles
people say my mum fucks women
thick filament
- myosin
thin filament
- actin
sarcomere
- functional unit of contraction
myofibril
- string of sarcomeres
muscle cell
- bundle of myofibrils
- also called a myofiber
fascicle
- bundle of muscle cells
whole muscle
- bundle of fascicles
T tubules
- invaginations of the cell membrane
- allow action potential to travel into interior of cell
sarcoplasmic reticulum
- stores Ca2+
Z lines
- ends of the sarcomere
M line
- middle of the myosin filament
A band
- dark band at end of myosin filament
- full length of myosin and actin
I band
- light band at end of myosin filament
- region that is actin only
H zone
- zone where actin does not overlap myosin
- myosin only
In contraction
- you lose the H zone
- the I band becomes more narrow
- HI I’m gone!
crossbridge formation
- myosin binds to actin
- requires the presence of Ca2+
power stroke
- myosin pulls actin toward the center of the sarcomere
- ATP NOT USED HERE
- myosin returns to low energy position
release of actin
- requires presence of ATP
- ATP comes in and boots off actin
reset of myosin head
- resets to higher energy conformation
- requires ATP hydrolysis
when you run out of ATP
- you can’t release the actin
- rigor mortis
mysoin head groups operate
- asynchronously
- always need a “hand” on the rope to pull forward
excitation-contraction coupling
- happens in thin filament
- skeletal muscle cell depolarizes
- sarcoplasmic reticulum releases Ca2+ from voltage-gated Ca2+ channels
- Ca2+ levels in the cell increase
- troponin binds Ca2+
- troponin changes confirmation which moves tropomyosin
- myosin is now able to bind to actin and pull it to the midline -> contraction
motor units
- a neuron plus all of the muscle cells it controls
- somatic neuron
contraction of motor unit
- all or none
contraction of whole muscle cell
- graded
- trigger more or less motor units depending on strength of contraction you need
large muscles
- muscles of arms and legs
- 1 neuron controls 1000 cells
small muscles
- mouth, faces, eyes, fingers
- 1 neuron controls 10-20 cells
gross motor control
- a few large motor units for mass action
fine motor control
- many small motor units for precise control
muscle energy sources
- creatine-P + ADP -> creatine + ATP (SLS)
- fastest
- shortest, most explosive movements
- glycolysis (2 net ATP, lactic acid)
- run full lap
- short term energy
- aerobic respiration (30 ATP, 6 CO2, 6 H2O)
- slowest
- endurance activity
myoglobin
- stores O2 inside skeletal muscle
- 1/4 of a hemoglobin
oxygen debt
extra oxygen needed after exercise to:
- replenish O2 on myoglobin
- convert lactic acid into pyruvate in the liver
Bohr effect
rightward shift due to
- pH decrease
- increase pCO2
- increase temp
- 2,3-bisphosphoglycerate
- hemoglobin has a lower affinity for oxygen and will deliver more to tissues.
slow twitch fibers also referred to as
- red oxidative or slow oxidative
slow twitch fibers myoglobin content
- high
slow twitch fibers capillary network
- dense
slow twitch fibers speed of contraction
- slow
slow twitch fibers mitochondrial numbers
- large
slow twitch fibers fatigue resistance
- high
slow twitch fibers force generated
- low
slow twitch fibers example
- thigh muscles of marathon runners
type IIA fast twitch fibers referred to as
- white oxidative
type IIA fast twitch fibers myoglobin content
- medium
type IIA fast twitch fibers capillary network
- some
type IIA fast twitch fibers speed of contraction
- medium
type IIA fast twitch fibers mitochondrial numbers
- medium
type IIA fast twitch fibers fatigue resistance
- medium
type IIA fast twitch fibers force generated
- medium
type IIA fast twitch fibers example
- thigh muscles of 5K runners
type IIB fast twitch fibers also referred to as
- white fast twitch
type IIB fast twitch fibers myoglobin content
- low
type IIB fast twitch fibers capillary network
- sparse
type IIB fast twitch fibers speed of contraction
- fast
type IIB fast twitch fibers mitochondrial numbers
- low
type IIB fast twitch fibers fatigue resistance
- low
type IIB fast twitch fibers force generated
- high
type IIB fast twitch fibers example
- thigh muscles of sprinters.
function of cardiac muscle
- autonomic (involuntary)
- autorhythmic
location of cardiac muscle
- heart only
nuclei of cardiac muscle
- mononucleated
microscopic appearance of cardiac muscle
- striated
- put together the same way as skeletal muscle and contracts the same way
- Ca2+ can come from extracellular environment
function of smooth muscle
- autonomic NS (involuntary)
- neural stimulation
- hormones (oxytocin trigger contraction)
- mechanical (food trigger contraction)
- autorhythmic
location of smooth muscle
- walls of hollow organs
- stomach, bladder, intestinal, blood vessels
nuclei of smooth muscle
- mononucleated
microscopic appearance of smooth muscle
- nonstriated
osteoblasts
- builder
- able to divide, immature cell
- produce matrix
- calcitonin
osteocytes
- mature
- maintain the bone matrix
- usually don’t divide
matrix divides into
- fibers
- ground substance
fibers
- collagen - strength
- elastic - flexible, recoil
ground substance
- liquid from plasma
- solid bone
epiphysis
- end of the bone
diaphysis
- middle of the bone
epiphyseal plate
- growth plate
- separates epiphysis and diaphysis during childhood
spongy bone
- inside bone between epiphysis and diaphysis
medullary cavity
- filled with
- yellow marrow
- red marrow
yellow marrow
- lipids
red marrow
- red blood cell synthesis
lacunae
- houses for the osteocytes with extensions connecting to other lacunae
canaliculi
- cytoplasmic extension between osteocytes and central canal
- allow osteocytes to get rid of waste products
central canal
- blood supply
- find osteocytes all along the rings of the osteon
parathyroid hormone
- released due to low blood calcium
- stimulates bone breakdown by osteoclasts
- increase calcium reabsorption in kidneys
- increase absorption of calcium in small intestine
calcitonin
- tone down the Ca2+
- stimulates bone formation by osteoblasts
- decreases calcium reabsorption in kidneys
- decreases absorption of calcium in small intestine
- made by thyroid hormone
role of vitamin D
- vitamin D converted to calcitriol via PTH
- acts like PTH
osteoclasts
- bone breakdown
- activated by PTH
functions of respiratory system
- gas exchange
- short term pH regulation (fast)
ventilation
- move air in/out of the system
- conduction zone
respiration
- gas exchange
external respiration
- lung/blood
internal respiration
- blood/tissue
role of nose/nasal cavity
- warm air
- humidify air
- filter air
- smell
ciliated columnar cells
- line the respiratory epithelium in the nasal cavity
- mucociliary escalator
larynx
- all cartilage
role of larynx
- separate air from food
- maintain open airway (keeps trachea open)
- vocal folds
- voice box (voice production)
nasopharynx
- portion behind nasal cavity
- air only
- respiratory epithelium
oro- laryngo-pharynx
- portion behind oral cavity
- portion behind larynx
- air and food
- many flat tissues built up on one another for protection
epiglottis
- separates trachea and esophagus
trachea
- rings of cartilage connected by bands of tissue membrane
organization of bronchi
- R/L primary bronchi
- secondary (lobar) bronchi
- tertiary bronchi
- terminal bronchioles
cartilage of primary bronchi
- rings of cartilage
- a lot like we saw it in the trachea
smooth muscle of primary bronchi
- little smooth muscle
lining cells of primary bronchi
- ciliated columnar cells
cartilage of secondary bronchi
- irregular plates of cartilage
smooth muscle of secondary bronchi
- little smooth muscle
lining cells of secondary bronchi
- ciliated columnar cells
cartilage of tertiary bronchi
- no cartilage
smooth muscle of tertiary bronchi
- all smooth muscle
- acted on by sympathetic nervous system
- relaxes so you can get more air coming in
lining cells of tertiary bronchi
- ciliated columnar cells
cartilage of terminal bronchioles
- no cartilage
smooth muscle of terminal bronchioles
- all smooth muscle
lining cells of terminal bronchioles
- shorter cells
- no cilia
terminal bronchioles break into
- alveolar duct
type 1 cells
- gas exchange
- simple squamous
type 2 cells
- reduce surface tension inside alveolus
- makes breathing easier
- produces surfactant
- do not develop until 8th month
lungs are located where
- stuck to inside wall of chest cavity
- cannot inflate self. change size of chest cavity.
- surface tension between visceral and parietal pleura
- slight negative pressure between pleuras
inspiration
- active
- diaphragm contracts and move downward
- increase size of chest cavity
- decrease pressure
- air rushes in
expiration
- passive
- diaphragm relax
- elastic recoil of the lungs
- decease size of chest cavity
- increase pressure inside the lungs
- air is pushed out
force expiration
- active
- contract abdominal muscles
- increase pressure forcibly
diaphragm
- connected to parietal pleura
primary regulator of ventilation rate
- blood pH and pCO2
secondary regulator of ventilation rate
- pO2
three layers of skin
- epidermis
- dermis
- hypodermis
epidermis
- epithelial tissue
dermis
- connective tissue
hypodermis
- fat
- adipose tissue
cold thermoregulation
- no sweat
- shivering
- vasoconstriction
- piloerection (goosebumps)
heat thermoregulation
- sweat
- no shivering
- vasodilation
rigor mortis
- muscle in permanently rigid state
- can’t actively pump Ca2+ into SR
- myosin can’t detach from actin.
motor units versus size of units
- inverse relationship
how saturated is hemoglobin at the lungs?
- 98%
how saturated is hemoglobin at the tissues?
- 70%
connect tissue
- cells in a matrix
bone (skeletal system) functions
- support and movement
- protection
- mineral storage (calcium and phosphate)
- blood cell formation
compact bone
- dense, solid tissues
- makes up entire diaphysis and outer shells of epiphyses
spongy bone
- porous tissue
- makes up inner core of epiphyses
osteon
- unit of compact bone
everywhere two osteocytes connect
- joined by gap junctions
trachealis muscle
- makes up back of trachea
- allows diameter of trachea to change
- increase speed of airflow in trachea
alveolus
- where gas exchange actually takes place
- contains very thin walls
- found in clusters call
alveolar sacs
- clusters of alveolus
alveolar ducts
- tube leading into alveolar sacs
respiratory bronchioles
- tube leading into alveolar ducts
- composed of some alveoli
- branches off terminal bronchiole of conduction zone
terminal bronchiole
- has no alveoli so is part of the conduction zone
emphysema patients
- barrel chested
- can breathe in just fine.
- lungs expand but cannot elastically recoil
- have a hard time exhaling
