Here is term paper on ‘Human Muscles’. Find paragraphs, long and short term papers on ‘Human Muscles’ especially written for school and college students.

Term Paper on Human Muscles

Term Paper Contents:

  1. Term Paper on the Meaning of Human Muscles
  2. Term Paper on the Types of Human Muscles
  3. Term Paper on the Parts of Human Muscles
  4. Term Paper on the Fascicular Architecture of Human Muscles
  5. Term Paper on the Nomenclature of Human Muscles

Term Paper # 1. Meaning of Human Muscles:

ADVERTISEMENTS:

Muscle is a contractile tissue and primarily designed for movements.

L – Musculus = muscle

It resembles a mouse with their tendons representing the tail. All muscles are developed from mesoderm, except – arrector pilorum, muscles of iris and myoepithelial cells of salivary, sweat and lacrimal glands which are derived from ectoderm.

Term Paper # 2. Types of Human Muscles:

ADVERTISEMENTS:

Muscles have three types:

i. Skeletal muscles,

ii. Smooth muscles,

iii. Cardiac muscles.

ADVERTISEMENTS:

Below the characters of above three muscles have been described:

I. Skeletal Muscles (Striped, Striated, Somatic and Voluntary Muscles):

i. Skeletal muscles are most abundant and found attached to skeleton.

ii. They exhibit cross-striations under microscope.

ADVERTISEMENTS:

iii. These are supplied by somatic nerves (cerebro spinal) and are under voluntary control.

iv. They response quickly to stimuli and is also being capable of rapid contractions and get fatigued easily.

v. It helps in adjusting the individual to external environment.

vi. These are under highest nervous control of cerebral cortex.

ADVERTISEMENTS:

vii. In skeletal muscle, each muscle fibre is multinucleated cylindrical cell; containing groups of myofibrils made up of myosin, actin, and trapomyosin – myofilaments – are actual centractile elements.

Example- Muscles of limbs and body wall.

II. Smooth Muscles (Plain, Unstriped, Non-Straited, Visceral and Involuntary Muscles):

i. These muscles often surround the viscera.

ADVERTISEMENTS:

ii. They do not exhibit cross-striations under microscope.

iii. These are supplied by autonomic nerves and are not under voluntary control (sympathetic).

iv. They respond slowly to stimuli, being capable of sustained contraction and do not fatigue easily.

v. They also provides motor power for digestion, circu­lation, secretion and excretion.

vi. These are less dependent on nervous control, capable of contracting spontaneously, automatically and often rhythmically.

vii. In smooth muscles, each muscle fibre is an elongated, spindle shaped cell, with a single nucleus placed centrally. Myofibrils show longitudinal striations, e.g., muscles of blood vessels and G.I.T., G.U.T., arrectorpili muscles of skin.

III. Cardiac Muscles:

i. It forms myocardium of the heart.

ii. They are intermediate in structure, being striated and involuntary.

iii. These are meant for automatic and rhythmic contractions.

iv. In cardiac muscles. each muscle fibre has a centrally placed single nucleus.

v. In these muscles, fibres branch and anastomose with neighbouring fibres at inter-calated discs (opposed cell membranes).

vi. It’s Cross-striations are less prominent than skeletal muscles.

Myoepithelial Cells:

i. Myoepithelial cells are basic muscular cell belonging to smooth muscle type.

ii. Myoepithelial cells are present at bases of secretary acini of sweat gland and help in expulsion of secretion from acini.

Term Paper # 3. Parts of Human Muscles:

Two Ends:

i. Origin – Proximal and fixed.

ii. Insertion – Moving and distal.

Two Parts:

i. Fleshy part – contractile – belly.

ii. Fibrous part – non-contractile – tendon, aponeurosis etc.

Structure of Skeletal Muscle:

I. Contractile Tissue – Myofibrils:

i. Dark band,

ii. Light band.

II. Supporting Tissue:

i. Endomysium

ii. Perimysium

iii. Epimysium.

Term Paper # 4. Fascicular Architecture of Human Muscles:

Arrangement of muscle fibres varies according to direction, force and range of movement at a joint.

I. Parallel – Fasciculi:

i. Thyrohyoid

ii. Sternohyoid

iii. Biceps, digastric etc.

II. Oblique – Fasciculi:

i. Temporalis

ii. Flexor pollicis longus

iii. Rectus femoris

iv. Deltoid

v. Tibialis anterior

III. Spiral or Twisted Fasciculi:

i. Masseter

ii. Sternocleidomastoid (cruciate)

iii. Trapezius.

Term Paper # 5. Nomenclature of Human Muscles:

Depends on number of ways, e.g.:

i. According to shape, e.g., Trapezius, rhomboideus etc.

ii. According to number of heads of origin, e.g., Biceps, quadriceps, triceps, digastric.

iii. According to gross structure, e.g., Semi-tendinosus, semi-membranosus etc.

iv. According to location, e.g., Temporalis, supraspinatous, intercostals etc.

v. According to attachments, e.g., Stylohyoid, cricothyroid etc.

vi. According to function, e.g., Adductor longus, flexor-carpi ulnaris etc.

vii. According to direction of fibres, e.g., Rectus abdominis, obliquus abdominis, transversus etc.

Blood Supply of Skeletal Muscles:

Derived from neighbouring arteries. Arteries, veins and nerves pierce the muscle at a point known as neurovascular hilum.

Lymphatics:

Accompany blood vessels and drain into neighbouring lymph nodes.

Nerve Supply:

i. Motor nerve – 60%

ii. Sensory fibres – 40%

Actions of Muscles:

When a muscle contracts it shortens by 1/3 (30%) of its belly length and brings about a movement.

i. Prime movers- Bring about desired movement (Agonists).

ii. Antagonists- (opponents) – oppose the prime movers.

iii. Fixators- Which stabilize the proximal joints of a limb so that desired movement at the distal joint may occur on a fixed base.

iv. Synergists- When prime movers cross more than one joint, the undesired actions at the proximal joints are prevented by certain muscles known as synergists.

Applied Anatomy:

i. Paralysis- Loss of motor power is paralysis.

ii. Muscular spasm- Are quite painful and localized spasm caused by a muscle pull generalized spasm – occurs in tetanus and epilepsy.

iii. Disused atrophy and hypertrophy- Due to excessive use of muscles.

iv. Regeneration of skeletal muscle- Is limited, in large damage – no regeneration.

Missing or damaged muscle is replaced by connective tissue.

v. Sprain- Due to overstretching of muscle fibres.

vi. Tumours- Sarcoma.