Cat Dissection By: Brigid Tracy; Haylee Alonso;

Jess Duthie; Nicole Chagachbanian, Hannah Grogan

Important Terms • Cranial- toward or pertaining to the head • Caudal- toward or pertaining to the tail or rear• Rostral- the most forward portion of the body• Dorsal- toward the back • Ventral- away from the back or toward

the belly• Medial- toward the middle • Lateral- away from the middle• Proximal- the point nearest to the central axis • Distal- the point furthest from the central axis• Superficial- toward the surface• Deep- away from the surface• Superior- toward the top of a vertical plane• Inferior- away from the top of a vertical plane

Tools • Blunt probe- very useful in tearing through connective tissue• Scissors- used to cut through skin, muscle• Scalpel- used to gently scrape away connective tissue • Needle probe- used as a pointer,

or to attach the specimen to the dissecting tray • Forceps- used to grasp small objects and to remove connective tissue • Protective gear- because the preservative can be irritating to

your skin and damage you clothes

Head and Neck• Pinnae(external ears)• Eyes

• Superior palpebrae( upper eyelids)• Inferior palpebrae(lower eyelids)• Nostrils( external nares)• Vibrissae (whiskers)• Nicitating membrane-

originates in the lower medial corner of the eye; transparent 3rd eyelid

Trunk • Thoracic region• Abdominal region• Pelvic region• Pectoral region- ventral side of thorax• Back- dorsal side of thorax• Nipples- ventral surface of trunk

in thoracic and abdominal regions; 2 rows of paired nipples associated with mammary glands• Genital region- posterior end of the pelvic region in both sexes• Testes

• Penis • Urogenital aperture- external opening to the vagina and urethra

Useful Terms • Flexion- decrease in the angle at the joint between articulating bones• Extension- decrease in the angle at a joint• Abduction- movement away from the body's midline• Adduction- movement toward the body’s

midline• Rotation- movement around a central axis• Supination- lateral rotation of the hand

upward• Pronation- medial rotation of the hand

downward • Eversion- rotation of the sole of the foot outward

• Inversion- rotation of the sole of the foot inward• Circumduction- rotation of a limb around a central axis

Limbs and Tail • Limbs- as a typical quadruped mammal, the cat has four limbs- two upper forelimbs and two lower hind limbs. • Tail- is covered with variable amounts of fur and is useful as a rudder and balance beam during locomotion

Skinning

Pectoralis Major

• Origin: cranial half of sternum

• Insertion: proximal third of the humerus

• Action: adduction of the forelimb

Pectoralis Minor

• Origin: six vertebrae or xiphoid process

• Insertion: ventral border of the humerus

• Action: adduction of the forelimb

External Oblique

• Origin: lumbodorsal fascia of the caudal ribs

• Insertion: sternum and along linea alba

• Action: compression of the abdomen

Internal Oblique

• Origin: lumbodorsal fascia of the caudal ribs

• Insertion: sternum and along the linea alba

• Action: compression of the abdomen

Transverse abdominis

• Origin: aponeurosis of the caudal costal cartilages, lumbar vertebrae, and ventral border of ilium

• Insertion: along linea alba

• Action: compresses the abdomen

Rectus Abdominis

• Origin: iliac crest

• Insertion: cartilage of the S’h-7’h ribs and the xiphoid

• Action: compresses the abdomen and flexes the trunk

Trapezius

• Origin: 7th thoracic vertebrae and thoracic vertebrae

• Insertion: acromion process, scapula, and clavicle

• Action: extends humerus, adducts scapula

Latissimus Dorsi

• Origin: 4th or 5th thoracic vertebrae to the 6th lumbar vertebrae

• Insertion: Medial surface of the humerus

• Action: pulls forelimb dorsocaudally

Sternomastoid

• Origin: cranial border of the manubrium

• Insertion: lamboidal ridge and mastoid process of the temporal bone

• Action: contraction by both will flex head; individual contraction will rotate head

Cleidomastoid

• Origin: mastoid process of temporal bone

• Insertion: lamboidal ridge and mastoid process of the temporal bone

• Action: contraction by both will flex head; individual contraction will rotate head

Biceps Brachii

• Origin: scapula

• Insertion: radius

• Action: flexion of the forearm, but also supinates the Manus and stabilizes the shoulder joint

Triceps Brachii

• Origin: lateral head of the humerus; long head (scapula); medial head (medial side of humerus)

• Insertion: Olecranon process of ulna

• Action: extension of antebrachium

Sartorius

• Origin: iliac crest

• Insertion: fascia surrounding the knee and tibia

• Action: adduction and rotation of the femur and extensions of the shank

Gracilis

• Origin: Ischium and pubis

• Insertion: thin Apo neurosis associated with the shank

• Action: adducts and retracts the thigh

Biceps Femoris

• Origin: one head in the cat; ischium

• Insertion: tibia and patella

• Action: abducts the thigh and flexes the shank

Semitendinosis

• Origin: ischium

• Insertion: medial surface of the tibia

• Action: flexes lower leg

Vastus Medialis

• Origin: shaft of the femur

• Insertion: tibia

Rectus Femoris

• Origin: ilium near acetabulum

• Insertion: tibia

Vastus Lateralis

• Origin: greater trochanter and shaft of femur

• Insertion: tibia

Gastrocnemius

• Origin: lateral head (patella/femur/tibia) medial head (femur)

• Insertion: Achilles tendon that attaches to calcaneus bone

• Action: extends the pes and flexes the antebrachium

Achilles tendon

Gluteus Maximus (smaller)

• Origin: transverse processes of the last sacral and first caudal verterbrae

• Insertion: greater trochanter of femur

• Action: abducts thigh

Gluteus Medius (bigger)

• Origin: iliac crest, last sacral vertebrae, 1’ caudal vertebrae

• Insertion: greater trochanter of the femur

• Action: abducts the thigh

External Intercostals

• Origin: cranial rib

• Insertion: adjacent caudal rib

• Action: protraction of the irbs, which is required for inspiration

Longissimus Dorsi

• Origin: spines of vertebrae; ilium

• Insertion: processes of more cranial vertebrae

• Action: extends the vertebral column

Gastrointestinal tract

Long winding tube that carries food through its length

Esophagus: Liver: Stomach: Small Intestine: Large intestine:

Accessory organs

Supportive organs that lie outside the GI tract (teeth salivary glands, liver, gallbladder, and pancreas)

Diaphragm

An internal muscular partition dividing the thoracic and abdominopelvic cavity

Lingual frenulum

The ventral fold of tissue attaching the tongue to the floor of the mouth

Filiform

Sharp projections off of the cats tongue to give a friction surface for grooming

Esophagus

Long, muscular tube that transports swallowed materials from the pharynx to the stomach(behind trachea)

Mesentery

Double layer of peritoneum that extends from the visceral peritoneum of the small and large intestines to the dorsal abdominal wall

Liver

Prominent, dark-brown organ lying immediately deep to the diaphragm with most of its bulk on the right side

Gallbladder

Thin walled sac that receives newly manufactured bile from the liver for temporary storage

Stomach

J-Shaped enlargement of the GI tract; functions as a temporary reservoir for swallowed food

Small Intestine

Long winding tube that finalizes chemical digestion and is the only side for nutrient absorption

Large Intestine

Caudal portion of the GI tract; absorbs water from the contents that arrive from the small intestine, prepares and forms the feces

Rectum

Terminal segment of the large intestine

Pancreas

Located just below the greater curvature of the stomach; functions in the secretion of hormones that regulate blood sugar levels, secretion of digestive enzymes and sodium bicarbonate

Larynx

Box like structure composed of 5 cartilages that create a small chamber; houses the vocal cords which produces sound when exhaled air in channeled through

Trachea

Tubular air passageway extending from the larynx to the thoracic vertebra, where it divides

Lungs

Multi-lobed structures located lateral, cranial, and caudal to the heart; consists of many air-filled alveoli

Kidneys

Bean shaped organs partially embedded in fat against the dorsal body wall

Ureters

Narrow tubes that transport urine from the kidneys to the urinary bladder at the base of the pelvic cavity

Urinary Bladder

Reservoir for urine; has the ability to expand

Thoracic Cavity

(or chest cavity) is the chamber of the human body (and other animal bodies) that is protected by the thoracic wall (thoraciccage and associated skin, muscle, and fascia).

Pleural Cavity

a closed space (like the inside of a balloon) within which the lung has grown. As the lung grows into the space, it picks up a layer of pleura (outside of balloon) and this is called the visceral pleura. The remainder of the pleura is called the parietal pleura.

Pericardial Cavity

or pericardial space) is a potential space between the parietal pericardium and visceral layer. It contains a supply of serous fluid. The serous fluid that is found in this space is known as thepericardial fluid.

Apex and Base

Base: The part of the heart formed mainly by the left atrium and to a lesser extent by the posterior part of the right atrium, directed backward and to the right, and separated from the vertebral column by the esophagus and aorta.Apex: the blunt extremity of the heart formed by the left ventricle

Family Picture