LAB5 Flashcards
occipitofrontalis frontal belly
draws scalp anteriorly
occipitofrontalis (occipital belly)
draws scalp posteriorly
orbicularis oculi
closes the eye
orbicularis oris
shapes lips during speech
platysma
depresses the mandible
masseter
elevates the mandible
temporalis
elevates the mandible; retracts it too
sternocleidomastoid
extends the head at the atlanto-occipital joints
external abdominal oblique
flexes the vertebral column (both)
laterally flexes the vertebral column (singly)
internal abdominal oblique
flexes the vertebral column (both)
laterally flexes the vertebral column (singly)
rectus abdominis
flexes the vertebral column
transversus abdominis
compresses the abdomen
diaphragm
changes vertical dimension of the thoracic cavity (contraction & relaxation - inhalation & exhalation)
serratus anterior
abducts the scapula; rotates it upward too
trapezius
stabilizes the scapula; middle fibers adduct the scapula
biceps brachii
flexes the forearm at the elbow joint;
supinates forearm at radioulnar joints;
flexes arm at the shoulder joint
brachioradialis
flexes the forearm at the elbow joint
deltoid
abducts the arm at the shoulder joint
latissimus dorsi
extends the arm at the shoulder joint:
adducts and medially rotates it too
pectoralis major
adducts the arm at the shoulder joint;
medially rotates it too
triceps brachii
extends the forearm at the elbow joint;
extends the arm at the shoulder joint
biceps femoris
extends thigh at hip joint
semitendinosus
extends thigh at hip joint
semimembranosus
extends thigh at hip joint;
flexes leg at knee joint
gastrocnemius
flexes leg at knee joint;
plantar flexes foot at ankle joint
gluteus maximus
extends leg at hip joint;
laterally rotates leg at hip joint
gluteus medius
abducts the thigh at hip joint
quadriceps femoris
extends leg at knee joint
vastus lateralis
extends leg at knee joint
vastus medialis
extends leg at knee joint
vastus intermedius
extends leg at knee joint
rectus femoris
flexes thigh at hip joint;
flexes leg at knee joint
soleus
plantar flexes foot at ankle joint
tibialis anterior
dorsiflexes foot at ankle joint;
inverts foot at intertarsal joints
gracilis
adducts thigh at hip joint;
flexes leg at knee joint
what bones consist the pectoral girdle?
- scapula
- clavicle
what is the scapula’s acromion?
flattened, expanded process that articulates with clavicle’s acromial end
forms acromioclavicular joint
what is the scapula’s coracoid process?
lateral end of scapula’s superior border, attachment point for tendons and ligaments
what is the scapula’s spine?
prominent ridge that runs diagonally across scapula’s posterior surface
what is the scapula’s glenoid cavity?
cavity that articules with humerus’s head
forms glenohumeral joint
what is the clavicle’s sternal end?
rounded, articulates with sternum’s manubrium to form sternoclavicular joint
what is the humerus’s head?
head that articulates with scapula’s glenoid cavity to form glenohumeral joint
what is the ulna’s head?
head at distal end (near wrist) that is separated from wrist with a disc of fibrocartilage
what is the ulna’s olecranon?
process at proximal end of ulna that allows articulation between ulna and humerus
what is the radius’s head?
head at proximal end of radius that articulates with capitulum of humerus and radial notch of ulna
what are the carpals?
proximal region of hand, 8 bones
what are the metacarpals?
intermediate region of hand, 5 bones
what are the hand’s phalanges?
distal end of hand, bones of digits, 14 phalanges
I - thumb
V - pinky
what bones form the pelvic girdle?
two coxal(hip) bones
what is the function of the pelvic girdle?
connects the bones of the lower limbs to the axial skeleton
what is the function of the pectoral girdle?
connects the bones of the upper limbs to the axial skeleton
what bones form the pelvis?
- the coxal bones
- sacrum
- coccyx
what are the three bones that form each coxal bone?
- ilium
- ischium
- pubis
what is the acetabulum?
socket formed by ilium, ischium, and pubis that articulates with the head of the femur to form the hip joint
what is the ilium’s iliac crest?
super border of ilium, ends anteriorly by anterior iliac spine
what is the ilium’s greater sciatic notch?
notch where sciatic nerves pass
what is the sacroiliac joint?
articulation of sacrum and ilium
what is the ischium?
bone one sits on, inferior posterior portion of coxal bone
what is the ilium?
superior portion of coxal bone
what is the pubis?
inferior, anterior portion of coxal bone
what is the obturator foramen?
largest foramen in the skeleton, nearly completely closed by fibrous obturator membrane
what is the pubis’s pubic arch?
arch formed by converge of inferior rami of pubis and the two pubic bones
what is the pubic symphysis?
cartilaginous joint made of fibrocartilage between the two pubis bones
what is the femur’s head?
head of femur that articulates with the coxal bone’s acetabulum to form the hip joint
what is the femur’s neck?
constricted region distal to the femur’s head
what is the patella?
small, sesamoid bone anterior to the knee joint
increases leverage of the tendon of the quadriceps femoris
what is the tibial tuberosity?
point of attachment for patellar ligament on tibia’s anterior surface
what is the tibia’s medial malleolus?
prominence on medial surface of leg that articulates with the talus
what is the fibula?
bone lateral to tibia that stabilizes ankle joint and articulates with tibia at fibular notch to form the distal tibiofibular joint
what are the tarsals?
proximal region of foot, 7 bones
what is the talus?
ankle bone that articulates with tibia and fibula to form the ankle joint
what is the calcaneus?
strongest tarsal bone located at the heel/posterior part of feet
what are the metatarsals?
bones on the feet that articulate proximally with tarsals and distally with the phalanges
what are the feet’s phalanges?
distal end of feet, bones of digits, 14 phalanges
how is the pubic arch different btwn males and females?
males: <90°
females: >90°
how is the obturator foramen different btwn males and females?
males: round
females: oval
how is the pelvic inlet different btwn males and females?
males: narrow, heart shaped
females: wide, more oval shaped
how is the composition of bone different btwn males and females?
males: harder and denser
females: lighter and less dense
how is the greater sciatic notch different btwn males and females?
males: ~70°, inverted V
females: ~90°
what are articulations?
points of contact btwn bone and another bone, cartilage, or tooth
what are the three structural types of joints?
- fibrous
- cartilaginous
- synovial
what are fibrous joints?
articulations held together by dense irregular connective tissue, have no synovial cavity, and exhibit little to no movement
what are the classifications for fibrous joints?
- sutures
- syndesmoses
what are sutures?
- articulations found only between skull bones
- thin layer of connective tissue between them
- immovable
what are synostoses?
sutures that fused into a bony joint
what is a syndesmosis?
- articulations with structures farther apart than in sutures
- dense irregular connective tissue
what are the classifications of syndesmoses?
- interosseous ligaments
- interosseous membranes
- gomphoses
what are interosseous ligaments?
- found between distal ends of tibia and fibula
- permits slight movement
what are interosseous membranes?
- sheet of dense irregular connective tissue
- occur between tibia and fibula
- found between ulna and radius
- permits slight movement
what is a gomphosis?
- permits small shock-absorbing movements
- found between roots of teeth and their sockets in mandible and maxillae
what are cartilaginous joints?
joints that unite two structures with hyaline cartilage or fibrocartilage
what is a synchondrosis?
- joint composed of a solid piece of cartilage that connects two bones
- connected by a thin layer of hyaline or fibrocartilage
- allows little to no movement
what type of joints are epiphyseal cartilages?
synchondroses
- immovable
- ossifies and becomes synostoses as a child ages
what is a symphysis?
ends of articulating bones covered with hyaline cartilage with a disc of fibrocartilage between them
- slightly movable because of collagen fibres in fibrocartilage
what are examples of symphyses?
- pubic symphysis
- intervertebral discs
- manubrium and body of sternum
what are synovial joints?
joints with a synovial cavity between articulating bones
- articulating surfaces of bones are covered by hyaline cartilage
- two layers enclose the cavity
- outer fibrous membrane
- inner synovial membrane
what is the function of synovial fluid?
- lubricates joints, reducing friction
- absorbs shocks
- contains phagocytic cells that remove microbes and debris due to wear and tear at joints
what are the two types of joints that can form synostoses?
- sutures
- epiphyseal cartilages
what are the four main categories of movement at synovial joints?
- gliding
- angular
- rotation
- special movements
gliding
flat bone surfaces move:
- side to side
- back and forth
joints that can glide?
- intercarpal joints
- intertarsal joints
flexion
decreases angle between articulating bones
extension
increases angle between articulating bones
lateral flexion
decreases angle between articulating bones along the coronal plane
joints that can laterally flex?
intervertebral joints
abduction
movement of bone away from midline
adduction
movement of bone toward midline
circumduction
movement of distal end of a body part in a circle
rotation
bone revolves around its own longitudinal axis
medial rotation
anterior surface of limb bone is turned toward midline
lateral rotation
anterior surface of limb bone is turned away from midline
elevation
superior movement of body part
depression
inferior movement of body part
dorsiflexion
bending of foot at ankle joint in direction of dorsum
plantar flexion
bending of foot at ankle joint in direction of plantar/inferior surface
supination
movement of forearm at proximal and distal radioulnar joints, radius and ulna parallel, palm turned anteriorly
pronation
movement of forearm at proximal and distal radioulnar joints, radius distal end crosses over ulna distal end, palm turned posteriorly
what are the types of synovial joints?
- plane
- hinge
- pivot
- saddle
- ellipsoid
- ball-and-socket
what is the movement that occurs at a synovial joint dependent on?
supporting ligaments and muscles and on the shape of the articulating bones
what are monaxial/uniaxial joints?
joints limited to movements around one axis
what are biaxial joints?
joints limited to movements around two axes at right angles to each other
what are triaxial/multiaxial joints?
joints capable of movement around three axes
what are plane joints?
joints with flat or slightly curved articulating bones which permit gliding movements
- biaxial
- acromioclavicular joint
- intertarsal joints
- intercarpal joints
what are hinge joints?
joints where the convex surface of one bone fits into the concave surface of another
- uniaxial
- humerus-ulna joint
- interphalangeal joints
what are pivot joints?
one bone rotates around its own long axis
- monaxial
- radius-ulna joint
- atlanto-axial joint
what are ellipsoid joints?
oval shaped depression of one bone and the oval shaped projection of the other fit together
- biaxial
- radius and carpal bones
- between metatarsals and phalanges
what are saddle joints?
concave surface of one bits fits over the convex surface of another
- biaxial
- allows more movement than an ellipsoid joint
- btwn metacarpal of thumb and its carpal
- manubrium-sternum-clavicle joint
what are ball-and-socket joints?
ball-like surface of one bone fits into a cup-shaped depression of the other bone
- triaxial
- hip joint
- shoulder joint
what are some functions of skeletal muscles?
- producing body movements
- thermogenesis
- storing and moving substances within body
what is the origin?
bone a joint is attached to that remains stationary
what is the insertion?
bone a joint is attached to that moves toward the origin, generating the action
what is the insertion for muscles that cause facial expressions?
the skin
which muscles whose aponeuroses form the linea alba?
- external oblique
- internal oblique
- transversus abdominis
what is the linea alba?
- tough fibrous band extending from xiphoid process to pubic symphysis
- stretches to increase distance between rectus abdominis muscles in latter stages of pregnancy
what type of connective tissue forms the linea alba?
fibrous connective tissue
what layer of bone does a tendon attach to?
periosteum
what are muscles of the abdomen? list from deep to superficial
- transversus
- internal
- external
- rectus
what are muscles that act on mouth for facial expressions?
- occipitofrontalis
- orbicularis oculi
- masseter
