1016msc mid tri exam

What muscle inserts via the calcaneal tendon?

Gastrocnemius

I am a powerful extensor muscle of the thigh at the hip joint, and I am most active when climbing stairs. I arise from the dorsal ilium, sacrum and coccyx, and I insert on the gluteal tuberosity. I am the ________________.

Gluteus maximus

When Dorothy stops staring at her ruby slippers and lifts her head to look to the hills in the distance, the movement of her head and neck would be described as _______________, involving which muscle?

Extension of the head at the neck; splenius

When performing a bicep curl, the biceps brachii act as the ____ while the triceps brachii is the ____

Agonist and antagonist

What muscle is known as the boxer muscle?

Serratus Anterior

What muscle/ muscle group is a powerful knee extensor and hip flexor?

Quadriceps

A muscle with the term rectus has fibres that run in what direction?

Straight

When the terms biceps, triceps, or quadriceps forms part of a muscle's name, what does it tell you about the muscle?

THE MUSCLE HAS 2, 3 OR 4 ORIGINS RESPECTIVELY

The quadriceps femoris is composed of 3 vastus muscles and the ____

rectus femoris

What is the name for connective tissue surrounding an individual muscle fibre?

Endomysium

In general, a muscle that crosses over the anterior side of a joint produces ____-

Flexion

The supraspinatus is named for its location on the posterior aspect of the scapula above the spine. What is its action?

Abduction of the arm, stabilise shoulder joint & prevent downward dislocation of humerus

What muscle in the posterior trunk is in both opposite compartments and antagonists to abdominal muscles?

Quadratus lumborum

How does the scapula attach to the axial skeleton?

Muslce

_____________ ions are released from the sarcoplasmic reticulum and bind to the _______________ molecule in skeletal muscle cells.

Calcium and troponin

What bones form the nasal septum?

Vomer and ethmoid

Connective tissue surrounds a whole muscle?

Perimysium

A muscle that provides the major force for producing a specific movement is a/an _________?

Prime mover

What is the functional unit of skeletal muscle?

Sacromere

In muscle contraction, calcium _____

Removes the blocking action of tropomysosin

What structure units the coxal bone anteriorly?

Pubic symphysis

What joints are diathrotic?

Synovial joints

What process creates cranial bones/ long bones?

Cranial bones: intramembranous ossification ----- long bones: endochondral ossification

Epiphyseal plates form as a result of what ossification process?

Endochondral ossification

What bone cells are responsible for monitoring bone matrix?

Osteocytes

Which membrane lines internal cavities and covers the trabeculae of bone?

Endosteum

When do primary ossification centres develop?

8 weeks gestation

Where are secondary ossification centres located?

Epiphysis of long bones

What tissue forms the model for endochondral ossification?

Hyaline cartilage

What is marfans syndrome?

Genetic disorder of connective tissue

What is pituitary dwarfism?

Growth hormone deficiency; hyposecretion ; pituitary gland deficient in producing GH

What is achondroplasia?

Genetic disorder of cartilage/ long bone growth; Endochondral ossification affected

In a typical vertebra, the vertebral arch is formed by which component?

Lamina & pedicle

What are the 2 features of the vertebral column that give it flexibility?

Intervertebral discs & spinal curvatures

What does the ACL ligament do?

Attaches to femur.

Prevents forward sliding of the tibia on the femur.

Blocks hyperextension of the knee.

What structures make up the unhappy triad?

ACL / MCL / Medical meniscus

What are 3 types of fibrous joints?

Sutures

Syndesmosis

Gomphosis

what are features of skeletal muscle?

Voluntary

Long cylindrical fibres

Multinucleate

Striated

What are features of cardiac muscle?

Involuntary

Branched

Uni/binucleate

Striated

What are features of smooth muscle?

Involuntary

Fusiform fibres

Uninucleate

No striations

What are agonists?

Muscles that perform the action

What are prime movers?

The agonist most responsible for the movement

What are antagonists?

Muscles whose action opposes the agonist. Bicep curls= bicep brachii agonist and tricep brachii antagonist

Which muscles work together to perform the same task?

Synergists

What is an example of multipennate muscles?

Deltoid

What are fusiform muscles?

Muscles that are spindle shaped, with a wide centre that tapers down to narrow ends.

What is the function of erector spinae muscles?

Extension of the spinal column

The contraction of one quadratus lumborum muscle results in what movement?

Lateral flexion of the trunk if standing

Unilateral contraction of abdominal muscles results in what?

Rotation and lateral flexion of the trunk

What type of tissue is the linea alba made of?

Connective tissue (tendinous raphe)

Infraspinatus

Shoulder lateral rotation and rotator cuff stability

Levator scapulae

Scapula elevation and adduction

Biceps Brachii

Elbow flexion & supination

Rhomboids

Scapula adduction

Pectoralis major

Shoulder flexion, adduction and medial rotation

Triceps brachii

Elbow extension

Brachioradialias

Elbow flexion (with forearm semipronated)

Flexor carpi radialis

Wrist flexion and abduction

Supraspinatus

Shoulder abduction + rotator cuff stability

Extensor digitorum

Wrist & finger extension

Latissimus dorsi

Shoulder extension, adduction and medial rotation

Deltoid

Shoulder flexion, abduction and extension

Coracobrachialis

Shoulder flexion & adduction

2. muscles that sit in the anterior compartment that abduct the scapulae

Serratus anterior

Pectoralis minor

2. muscles that sit in the posterior compartment that adduct the scapulae

Rhomboid

Middle trapezius fibres

Muslces that abducts, flexes and extends the humerus.

Deltoid

What is the condition called due to overuse of the wrist extensor muscles?

Lateral epicondylalgia

What muscle is the primer mover for inspiration?

Diaphragm

What 2 muscles make up the pelvic floor?

Levator ani

Coccygeus

What is the sarcoplasmic reticulum?

- Stores calcium

- Surrounds each myofibril

What causes the striations that characterise skeletal muscle?

Thick myosin and thin actin filaments.

Name 2 contractile myofilaments specially arranged in each myofibril

Actin and myosin

What myofilament has a binding site for calcium?

Actin

When a muscle fibre contracts, the banding pattern changes:

I bands shorten

H zone disappears

Distance between Z discs shorten

3 stages of excitation - contraction coupling:

AP propagates along sarcolemma of muscle fibre and down T-tubules

Calcium ions released

Calcium ions bind to troponin

What event causes the power stroke in cross bridge cycle?

Release of inorganic phosphate first strengthens the attachment between myosin head and actin.

Release of ADP.

What 2 events are necessary for relaxation of the muscle fibre to occur?

- ATP binds to myosin head, link between actin and myosin weakens and detaches.

- Calcium ions actively pumped back.

What pathway is the fastest?

Direct phosphorylation - 1 ATP 10 - 15 seconds of energy

Which of these pathways provide the most ATP energy?

Aerobic pathway - 32 ATPs

What pathway is predominately used in endurance sports?

Aerobic pathway

Calcium ions bind to which molecule in the skeletal muscle cells?

Troponin

What are the major functions of intervertebral discs?

To absorb shock and provide flexibility to the spine

What are skeletal muscle fibres made of?

Myofibrils

What are myofibrils made up of?

Myofilaments

What are the 2 proteins that make up myofilaments?

Thin actin and thick myosin

What is the A band?

(dark) Actin and myosin filaments

What is the I band?

(Light) Actin and titin filaments

What is a sacromere?

The smallest functional unit of a muscle cell

What is the structure of myosin?

Thick, 2 heads attached to a tail. Forms cross bridge. Forms binding site for ATP

What is the structure of actin?

G actin binding site for myosin cross bridge. Tropomyosin blocks myosin binding site on actin.

What is troponins 3 polypeptide complex?

TN 1 binds to actin

TN T binds to tropomyosin

TN C binds to CA2

What is the sarcolemma?

Membrane that surrounds entire muscle cell

What is the cytoplasm inside a muscle cell called?

Sarcoplasm

What is the structure of sarcoplasmic reticulum?

Made up of smooth ER, connecting interconnecting tubulues

What does the sarcoplasmic reticulum do?

Stores calcium

What do T tubules do in the sarcoplasmic reticulum?

Connect to terminal cisternae of SR

What is the prime mover for shoulder extension?

Latissimus dorsi

What is the synergist of latissimus dorsi on extension?

Teres major

What are the shoulder abductors?

Supraspinatus - initiator

Deltoid - prime mover

What are the 4 rotator cuff muscles?