Lecture Exam 3- SG

What is the most common muscle type?

skeletal muscles

What is the relationship between skeletal muscle and tendons?

Tendons attach muscle to bone.

Epimysium

layer of dene irregular CT surrounding entire skeletal muscle tissue.

What is the epimysium made of?

dense irregular connective tissue

Adduction

body part moves toward the trunk in a medial direction.

Abduction

body part moves away from trunk in a lateral direction.

adduction vs abduction

ADDuction: movement toward midline
ABDuction: movement away from midline

Midline

vertical line in middle of the body dividing the body into equal left and right sides. Starts at top of head drawing straight down to the point between the two feet.

Muscles of the medial compartment of the thigh

gracilis,
pectineus,
adductor brevis,
adductor longus,
adductor magnus,
adductor minimus,
obturator externus

flexion

decreases the joint angle (in an anterior/posterior plane)

Extension

increases the joint angle (in an anterior/posterior plane)

flexion vs. extension

flexion- joint angle DEcreases

extension- joint angle INcreases

rotation

bone pivots on its own longitudinal axis

supination

lateral rotation of the forearm so that the palm of the hand is anterior

medial rotation

aka internal rotation.
turns anterior surface of bone medially.

Example of plantar flexion

ballerina on tippy toes.

example of dorsiflexion

digging in your heel

What is the perineum?

bottom region of pelvic cavity. Diamond- shaped region between lower appendages.
Bounded by pubic symphysis, coccyx, and ischial tuberosities.

How is the perineum divided?

into two triangular regions divided by a transverse (horizontal) line between ischial tuberosities.

What do you find in the urogenital triangle?

external genitalia and urethra.

What is the main function of the pelvic floor?

to provide support/ act as a "floor" for pelvic and abdominal viscera (including rectum)

What does the pelvic floor play a role in?

Continence of urethra, anus, and vaginal orifices (openings).

What are the muscles of the anterior abdominal wall?

internal oblique,
external oblique,
rectus abdominus,
transversus abdominus.

Are skeletal muscles voluntary or involuntary?

voluntary

Are skeletal muscles vascularized?

yes

Are skeletal muscles innervated?

yes

What are skeletal muscles innervated by?

Motor neurons

What gives long bones strength?

their curve/ bend

What is the importance of long bones?

Movement and support of body weight.

Where are long bones found?

upper legs, thigh, foot

Example of long bone

femur
humerus
phalanges

3 regions of long bone

epiphysis, metaphysis, diaphysis

Short bones

length is nearly equal to width.

Example of short bones

carpals,
tarsals,
wrist bones.

Irregular bones have

elaborate, sometimes complex shapes.

Example of irregular bones

maxilla,
sacrum,
mandible,
vertebrae.

Where can you find medullary cavity?

long bones

What is the medullary cavity filled with?

Yellow bone marrow

Is the medullary cavity filled with yellow or red bone marrow?

Yellow bone marrow

What is another name for red bone marrow?

myeloid tissue

What does red bone marrow consist of?

reticular CT, developing white blood cells, adipocytes

Red bone marrow is

hematopoietic- blood cell forming

What is the process of blood cell production?

hematopoiesis

Metaphysis

region of bone growth

Where is the epiphyseal plate found?

metaphysis

epiphyseal plate

region in children and young adults where bones elongate

What happens when the epiphyseal plate stops growing?

it turns into epiphyseal LINE (around 25-27 years)

Where can you find spongy bone?

At the ends of long bone.

Is spongy bone vascular or avascular?

highly vascularized.

What does spongy bone contain?

red bone marrow

Yellow bone marrow

product of red bone marrow degeneration as children age.
fatty substance.

When may yellow bone marrow convert back to red bone marrow?

with severe anemia

When yellow bone marrow converts back to red bone marrow it facilitates the production of

additional erythrocytes (red blood cells)

Osteoporosis

reduced bone mass (can compromise normal function).

With osteoporosis, reduced hormones with age (vitamin D, growth hormone, estrogen, testosterone) contribute to

a reduction in bone mass

What is the significance of osteoporosis is men vs. women?

prevalence and risk of fracture are higher in women than in men.

What is the endomysium made of?

areolar connective tissue

Fascicle

surrounded by perimysium

Perimysium

layer of dense irregular CT surrounding each fascicle.

What is perimysium made of?

dense irregular connective tissue

Myofibril

long, cylindrical organelle found in muscle cells

Endomysium

areolar CT surrounding each muscle fiber.

Sarcolemma

plasma membrane of a skeletal muscle fiber located below endomysium

Where is the sarcolemma located?

under endomysium

What are the functions of the skeletal system?

move body,
produce heat,
maintain posture,
protect and support,
regulation and elimination of materials.

Is cardiac muscle involuntary or voluntary?

involuntary

Where can you find cardiac muscle?

only in the heart

Is smooth muscle voluntary or involuntary?

involuntary

What muscles are involuntary?

cardiac and smooth

What muscles are voluntary?

skeletal muscles

Where can you find smooth muscle?

intestines, urinary tract

Ligaments

attach bone to bone

Tendons

attach muscle to bone

What attaches muscle to bone?

tendons

What attaches bone to bone?

ligaments

ligaments vs tendons

LIGAMENTS attach bone to bone.
TENDONS attach muscle to bone.

Aponeurosis

thin, flattened sheet of dense regular CT. attaches muscle to either bone, ligament, or fascia.

What kind of CT is the aponeurosis made of?

dense regular CT

Aponeurosis can attach muscle to

bone,
ligament,
or fascia.