BIOL 3410 Lab Practical 2

Myofibrils

Myofibrils

Microscopic protein filaments that make up muscle cells.

Endomysium

Connective tissue surrounding a muscle fiber

Epimysium

surrounds entire muscle

Perimysium

Connective tissue surrounding a fascicle

Insertion

the end that has attachment to movable bone

Orbicularis Oculi

Closes eyelids; used in blinking, winking, and squinting

Frontalis

raises eyebrows, wrinkles forehead

Zygomaticus Major

Muscles on both sides of the face that extend from the zygomatic bone to the angle of the mouth.
These muscles elevate the lip, pull the mouth upward and backward, as when you are laughing or smiling.

Zygomaticus Minor

retracts and elevates upper lip

Orbicularis Oris

Closes and protrudes lips; used in whistling and forming many letters during speech; the "kissing muscle"

Risorius

Draws corner of mouth laterally

Levator Labii Superioris

elevates upper lip

Masseter

elevates mandible and closes jaw

Temporalis

elevates and retracts mandible

Buccinator

compresses cheek

Platysma

Draws down the lower lip and angles of the mouth; tenses skin of the neck; helps depress mandible

Sternocleidomastoid

flexes neck; rotates head

Levator Scapulae

Origin: Transverse processes of the C1-C4 vertebrae.
Insertion: Medial border of the scapula between spine and superior angle.
Action: elevates and adducts scapula, bends neck laterally

Scalenes

elevates first two ribs

External / internal intercostals

expand and lower the ribs during breathing

External Oblique

Origin: External surfaces of ribs 5-12

Insertion: Anterior iliac crest and abdominal aponeurosis to linea alba

Action: flexes torso (draws thorax downward), rotates torso, laterally flexes torso

Internal Oblique

Origin: Anterior iliac crest, lateral half of inguinal ligament, and thoracolumbar fascia

Insertion: Costal cartilages of ribs 8-12; abdominal aponeurosis to linea alba

Action: flexes torso, rotates torso, laterally flexes torso

Transversus Abdominus

Origin: Anterior iliac crest, lateral half of inguinal ligament, thoracolumbar fascia and cartilages of ribs 6-12

Insertion: Abdominal aponeurosis to linea alba, xiphoid process and pubic symphysis

Action: compresses abdomen

Rectus Abdominus

Origin: Pubic crest and symphysis pubis of the hip bone

Insertion: Costal cartilages of ribs 5-7; xiphoid process of sternum

Action: flexes vertebral column (torso)

Serratus Anterior

protracts scapula, assists in upward rotation of scapula

Diaphragm

Large, flat muscle at the bottom of the chest cavity that helps with breathing

Pectoralis Major

Adducts and flexes humerus

Pectoralis Minor

protracts and depresses scapula

Erector Spinae Group

iliocostalis, longissimus, spinalis

Quadratus Lumborum

Origin: Medial half of the posterior iliac crest and iliolumbar ligament
Insertion: Transverse processes of L1-L4 and medial half of 12th rib

Rhomboid Major

Origin: Spinous process of T2-T5 vertabrae
Insertion: Medial border of scapula inferior to spina scapulae
Action: Retracts the medial border of scapula while it downwardly rotates the lateral angle. Elevates the medial border of scapula while it downwardly rotates the lateral angle

Rhomboid Minor

Origin: Spinous process of C7-T1 vertebrae
Insertion: Medial border of scapula superior to spina scapulae
Action: Retracts the medial border of scapula while it downwardly rotates the lateral angle. Elevates the medial border of scapula while it downwardly rotates the lateral angle

Splenius Capitis

Origin: Inferior half of ligamentum nuchae (C3-C6) and spinous processes of C7-T3
Insertion: Superior nuchal line of occipital bone and mastoid process of temporal bone
Action: Bilaterally extends head and neck. Unilaterally rotates head and neck to same side.

Trapezius

Origin: Medial superior nuchal line and external protuberance of occipital bone, ligamentum nuchae and spinous process of C7-T12.
Insertion: Lateral clavicle, acromion and spine of scapula.
Action: Upper fibers elevate and upwardly rotate scapula, extend neck

Latissimus Dorsi

Extends, adducts, and medially rotates the arm; draws the shoulder downward and backward

Deltoid

Origin:
a.Anterior (clavicular) head: anterior surface of the lateral clavicle.
b. Middle (acromial) head: acromion process and spine of the scapula.
Insertion: Deltoid tuberosity of the humerus.
Action: medially rotates the arm, abducts the arm

Supraspinatus

Origin: Supraspinous fossa of the scapula
Insertion: Superior aspect of the greater tubercle of the humerus
Action: abducts arm

Infraspinatus

Origin: Infraspinous fossa of the scapula
Insertion: Middle part of the greater tubercle of the humerus
Action: rotates arm laterally

Subscapularis

Origin: Subscapular fossa of the scapula.
Insertion: Lesser tubercle of humerus.
Action: medially rotates arm

Teres Major

Origin: Lower lateral border and inferior angle of the scapula
Insertion: Medial lip of the intertubercular (bicipital) groove of the anterior humerus.
Action: extends, adducts, and medially rotates arm

Teres Minor

Origin: Middle part of the lateral (axillary) border of the scapula.
Insertion: Inferior aspect of greater tubercle of humerus
Action: rotates arm laterally, stabilizes shoulder joint

Biceps Brachii

Flexes and supinates forearm

Brachialis

flexes forearm

Triceps Brachii

extends forearm

Brachioradialis

flexes forearm at elbow

Supinator

supinates forearm

Pronator Teres

pronates forearm

Palmaris Longus

flexes wrist

Flexor Carpi Radialis

flexes wrist and abducts hand

Flexor Carpi Ulnaris

Flexes and adducts hand at the wrist

Extensor Carpi Radialis Longus

Extends wrist and abducts hand

Extensor Carpi Ulnaris

extends and adducts wrist

Flexor Digitorum

flexes fingers

Extensor Digitorum

extends fingers

Anconeus

elbow

Gluteus Maximus

extends thigh

Rectus Femoris

Origin: Anterior inferior iliac spine and supracetabular groove of the ilium
Insertion: Tibial tuberosity (via patellar ligament)
Action: Flex the thigh and extend the leg

Gluteus Medius

abducts and medially rotates thigh

Vastus Lateralis

Origin: Greater trochanter of femur, intertrochanteric line, gluteal tuberosity and lateral aspect of linea aspera
Insertion: tibial tuberosity via the patellar ligament and also into the patella itself.
Action: Flex the thigh and extend the knee
Part of quadriceps femoris group

Tensor Fascia Latae

flexes and abducts thigh

Vastus Intermedius

Origin: Anterior and lateral surface of the femoral shaft
Insertion: Tibial tuberosity (via patellar ligament) and the patella itself
Action: Flex the thigh and extend the leg
Part of quadriceps femoris group

Adductor Brevis

adducts femur at hip

Vastus Medialis

Origin: Intertrochanteric line, spiral line and linea aspera, and the medial lip of linea aspera of femur
Insertion: Tibial tuberosity (via patellar ligament) and the patella itself
Action:Part of quadriceps femoris group, Flex the thigh and extend the knee

Adductor Longus

Origin: Superior aspect of pubis, below pubic tubercle
Insertion: Middle third of linea aspera of femur along medial lip
Action: Adducts the femur at the hip, flexes the thigh at the hip

Biceps Femoris

extends thigh and flexes knee, part of the hamstring group

Adductor Magnus

Origin: Oblique head - inferior ramus of pubis & ischial ramus, Vertical head - ischial tuberosity.
Insertion: Oblique head - gluteal tuberosity, linea aspera and proximal supracondylar line of femur, Vertical head - adductor tubercle of femur
Action: Adducts the femur at the hip, Flexes thigh

Semimembranosus

Flexes leg at the knee and extends thigh at the hip; belongs to the hamstring group

Gracilis

adducts thigh, flexes and medially rotates leg

Semitendinosus

Flexes leg at the knee and extends thigh at the hip; belongs to the hamstring group

Iliopsoas (iliacus and psoas major)

Flex trunk at hip joint, flex thigh; lateral flexion of vertebral column (psoas)

Pectineus

adducts, flexes, and medially rotates thigh

Sartorius

band-like muscle that extends from the anterior superior iliac spine to the medial side of the proximal tibia
This versatile muscle flexes the leg at the knee and flexes, abducts, and laterally rotates the leg at the hip.
This muscle allows us to sit cross-legged

Gastrocnemius

plantar flexes foot

Soleus

plantar flexes foot

Tibialis Anterior

dorsiflexes and inverts foot

Fibularis Longus

plantar flexes and everts foot

Spinal Cord

Nerves that run up and down the length of the back and transmit most messages between the body and brain

Conus medullaris

tapered end of spinal cord

Dorsal Root

the sensory branch of each spinal nerve

Ventral Root

the basal branch of each spinal nerve; carries motor neurons

Cauda Equina

collection of spinal nerves below the end of the spinal cord

Posterior Median Sulcus

a shallow vertical groove dividing the spinal cord throughout its whole length in the midline posteriorly.

Filum Terminale

anchors spinal cord to coccyx

Central Canal

A tiny channel found within the spinal cord and inferior medulla oblongata

Cervical Plexus

C1-C5

Brachial Plexus

C5-T1

Lumbar Plexus

L1-L4

Sacral Plexus

L4-S4

Dorsal Horn

Crescent shaped projection of gray matter within the spinal cord where sensory neurons enter the spinal cord

Ventral Horn

somatic motor neurons whose axons exit the cord via ventral roots

Lateral Horn

(only in thoracic and lumbar regions)
- sympathetic neurons

Gray Commissure

connects masses of gray matter; encloses central canal

Anterior Median Fissure

a groove along the anterior midline of the spinal cord that incompletely divides it into symmetrical halves

Dura Mater

a thick fibrous layer and a strong protective sheath over the entire brain and spinal cord. It is anchored to the inner surface of the cranium and vertebral cavity

Arachnoid Mater

a membrane of thin fibrous tissue that forms a loose sac around the CNS

Cerebrum

Area of the brain responsible for all voluntary activities of the body

Frontal Lobe

A region of the cerebral cortex that has specialized areas for movement, abstract thinking, planning, memory, and judgement

Parietal Lobe

A region of the cerebral cortex whose functions include processing information about touch, pressure, tickle, pain, itch, and vibration, as well as more general senses of the body such as proprioception and kinesthesia

Occipital Lobe

A region of the cerebral cortex that processes visual information

Temporal Lobe

A region of the cerebral cortex responsible for hearing and language.