Anatomy Lecture Exam 2

What are the functions of the muscular system?

perform body actions (movement, posture, visceral activities), thermoregulation, electric voltage

What are the muscle classifications?

color, histology, embryonic origin, morphologic appearance, location, control mechanism, actions

What are the muscle colors?

red or white

What are the muscle histologies?

smooth, cardiac, skeletal

What is the embryonic origin of muscle?

mesoderm

What are the muscle locations?

somatic or visceral

Defining traits of skeletal muscle

multinucleated and striated muscle fibers

Defining traits of smooth muscle

one central nucleus and non-striated

Defining traits of cardiac muscle

one central nucleus and striated

What is this muscle?

skeletal

What is this muscle?

cardiac

What is this muscle?

smooth

What make striations?

actin, myosin, troponin, tropomyosin

What is the epimysium?

cover entire muscles

What is the perimysium?

surrounds a muscle fascicle

What is the endomysium?

surrounds individual muscle cells

What part of the muscle connective tissue is in the small red circle (the top)?

endomysium

What part of the muscle connective tissue is the left blue arrow pointing to?

epimysium

What part of the muscle connective tissue is the blue arrow on the right pointing to next to the large red circle?

perimysium

What is the contraction principle (muscle stimulation)?

many motor neurons supply a muscle, each neuron innervates only a few fibers, selective recruitment of additional motor units can increase force

What is this muscle shape and what is its function?

parallel; abdominal muscles

What is this muscle shape and what is its function?

fusiform; biceps brachii, sartorius

What are these muscles shapes and what are their functions?

pennate (unipennate, bipennate, multipennate); digital extensor, rectus femoris, deltoideus

What is this muscle shape and what is its function?

circular; orbicularis oculi (eye)

Muscle extensors

increase joint angle

Muscle flexors

decrease joint angle

Abductors

move away from midline axis

Adductors

move towards midline axis

Protractors

push a body part away from its base

Retractors

pull a body part back

Levators

raise body parts

Depressor

lower body parts

Supinators

turns the palms upward

Pronators

turn the palms downward

Sphincters

constrict an opening

Constrictors

restrict a space

Rotators

turn part on its long axis

What attaches muscle to bone?

tendons

What attaches bone to bone?

ligaments

What is the aponeurosis?

flat sheet of connective tissue

What is the fascia?

thin casing of fibrous connective tissue around muscles, wrap and bind

Define synarthrotic (fibrous) joints

immovable, fibrous connective tissue

Define amphiarthrotic (cartilaginous) joints

limited movement, hyaline or fibrocartilage

Define diarthrotic (synovial) joints

freely moveable, hyaline cartilage

What is neurulation?

neural tube formation (dorsal ectoderm)

What forms from the axial mesoderm?

notochord, somites

What forms from the paraxial mesoderm?

somites (muscle, vertebrae, dermis)

Where do most axial skeletal muscles orginate from?

paraxial membrane

Somites become what?

trunk

Somitomeres become what?

head muscles

What does the hypomere become?

visceral smooth muscle, cardiac muscle

What does the mesenchyme become?

blood vessel smooth muscle, appedicular muscles

Where do axial muscles and fin muscles come from?

somites to myotome to axial muscles/fin muscles

Where do hypobranchial muscles (gill arches) come from?

somites to cervical myotomes to hypobranchial muscles (gill arches)

Where do cranial musculatures come from?

somitomeres to cranial musculatures

What species has the axial muscle in the picture?

teleosts, mostly undifferentiated epaxial and hypaxial (fish)

What species has the axial muscle in the picture?

salamanders, mostly undifferentiated epaxial; differentiated hypaxial (amphibians)

What species has the axial muscle in the picture?

lizards, differentiated epaxial and hypaxial

What appendicular muscles do teleosts have?

dorsal/ventral fin muscle is minor

What appendicular muscles do tetrapods have?

dorsal/ventral muscles prominent, pectoral girdle/forelimb, pelvic girdle/forelimb

What are the body cavities?

thoracic (pleural), abdominopelvic (peritoneal), pericardial

What are the sections of the thoracic cavity?

left, right

What are the sections of the abdominopelvic cavity?

abdominal, pelvic

What are serosal (serous) surfaces?

smooth membrane

What are the functions of the serosal surfaces?

secrete watery fluid that lubricates serosal surfaces; outer surface of organs, lines body cavities

What are the serosal membranes in the thorax/pleural cavity?

parietal pleura, visceral pluera

What are the serosal membranes in the abdomen/peritoneal cavity?

parietal peritoneum, visceral peritoneum

What are the serosal membranes in the pericardial cavity?

parietal pericardium, visceral pericardium

What is label 1?

visceral pleura

What is label 2?

parietal pleura

What is label 3?

intrapleural space (pleural cavity)

What is label 4?

thoracic wall

What is the pleural cavity made of?

connective tissue, simple squamous cells (mesothelium)

Where do two pleura meet?

hilum of lung (center)

What is the thin lining covering lungs?

visceral pleura

What is the lining covering internal surface of the thoracic cavity?

parietal pleura

What is the function of pleural fluid?

lubrication, surface tension (pneumothorax)

What are the arrows pointing to on this lung histology?

mesothelium (single squamous epithelial cell)

What is emphysema?

air under the visceral pleura

What is pneumothorax?

air between visceral and parietal pleura

What is the mesentary?

formed by double layers of serous membrane

What is the function of the mesentary?

suspends and holds organs loosely in place; contains blood vessels, nerves, lymphatics

What is the embryonic origin of the mesentary?

mesoderm

What is this image depicting?

embryonic mesentery development

What is the bottom arrow pointing to?

ventral mesenstary

What is the top arrow pointing to?

dorsal mesentary

What is the top arrow pointing to?

kidney - nephric ridge (retroperitoneal=behind)

What is the bottom arrow pointing to?

reproductive organs - genital ridge

What is the top arrow pointing to?

dorsal mesentery

What is the middle arrow pointing to?

visceral peritoneum

What is the bottom arrow pointing to?

parietal peritoneum

What happens to the ventral mesentaries?

usually lost

What are the remaining ventral mesenteries?

falciform ligament, lesser omentum

Where is the falciform ligament?

umbilicus to liver

Where is the lesser omentum?

liver to stomach/duodenum, ventral part of mediastinum

What supports the viscera?

dorsal mesenteries

What is 3?

parietal pleura

What is 2?

mediastinum

What is 1?

visceral pleura

What is the function of the mediastinum mesentery?

divides thoracic cavity into right and left cavities; contains heart, nerves, great vessels, lymph nodes