Chapter 1 – Introduction to Anatomy and Physiology

Anatomy

  • Anatomy – Form and structure
    • Subfields: microscopic anatomy; macroscopic (gross) anatomy; regional anatomy; systemic anatomy
  • Physiology – Functions
  • Study of the Animal Body

Microscopic vs Macroscopic Anatomy

  • Microscopic anatomy
    • Seen with a microscope
    • Key components: Cells; Tissue
  • Macroscopic (Gross) anatomy
    • Seen with unaided eye
    • Key components: Organs; Muscles; Bones
  • Micro- and Macroscopic Anatomy
    • Terms referring to the scale at which the body is studied

Regional and Systemic Anatomy

  • Regional Anatomy
    • Focus on an individual region (e.g., neck or abdomen)
    • Components considered in a region: Cells; Tissues; Blood vessels; Nerves; Muscles; Organs; Bones
  • Systemic Anatomy
    • Focus on an individual body system
    • Examples of systems: Skeletal system; Integumentary system; Nervous system; Cardiovascular system; Respiratory system; Digestive system; Muscular system; Sensory system; Endocrine system; Urinary system; Reproductive system

Anatomical Planes of Reference

  • Sagittal plane
    • Runs length of body
    • Divides into left and right parts
    • Not necessarily equal
  • Median plane
    • Special sagittal plane that runs down the center of the body lengthwise
    • Divides into equal left and right halves
  • Transverse plane
    • Divides body into cranial (head-end) and caudal (tail-end)
  • Dorsal plane
    • Plane at right angles to sagittal and transverse planes
    • Divides into dorsal (toward back) and ventral (toward belly)

Directional Terms

  • Left and right — always refers to the animal’s left and right
  • Cranial — toward the head
  • Rostral — toward the tip of the nose
  • Caudal — toward the tail
  • Dorsal — toward the back
  • Ventral — toward the belly
  • Medial — toward the median plane
  • Lateral — away from the median plane
  • Proximal — toward the body (extremity)
  • Distal — away from the body (extremity)

Common Regional Terms

  • Barrel — trunk of the body formed by rib cage and abdomen
  • Brisket — area at the base of the neck between the front leg; covers cranial end of sternum
  • Cannon — large metacarpal or metatarsal bone of hoofed animals
  • Fetlock — joint between cannon bone and proximal phalanx of hoofed animals
  • Flank — lateral surface of abdomen between last rib and hind legs
  • Hock — tarsus
  • Knee — carpus of hoofed animals
  • Muzzle — rostral part of the face formed mainly by maxillary and nasal bones
  • Pastern — area of the proximal phalanx of hoofed animals
  • Poll — top of the head between the bases of the ears
  • Stifle — femorotibial/femoropatellar joint equivalent to human knee
  • Tailhead — dorsal part of the base of the tail
  • Withers — area dorsal to scapulas
  • Carpus — carpal region (knee area in hoofed animals)

Body Cavities

  • Dorsal cavity
    • Central nervous system
    • Cranial cavity (cranium)
    • Spinal cavity (spinal canal)
  • Ventral cavity
    • Thorax and abdomen
    • Viscera

Ventral Body Cavity: Thorax (1 of 2)

  • Much larger than dorsal body cavity
  • Thorax (chest)
    • Cranial thoracic cavity – major structures include:
    • Heart
    • Major blood vessels
    • Lungs
    • Esophagus
  • Lining Membranes – pleura
    • Visceral layer
    • Potential space
    • Parietal layer
  • Inflammation – pleuritis / pleurisy

Ventral Body Cavity: Thorax (2 of 2)

  • (Covered above in part 1 of 2)

Ventral Body Cavity: Abdomen

  • Caudal abdominal cavity
  • Major structures – digestive organs – urinary organs – reproductive organs
  • Lining membranes – peritoneum
    • Visceral layer
    • Potential space
    • Parietal layer
  • Inflammation – peritonitis

Organization of the Body (1 of 2)

  • Cells – basic units of life – specialized function
  • Tissues – groups of specialized cells
    • Epithelial tissue
    • Connective tissue
    • Muscle tissue
    • Nervous tissue

Organization of the Body (2 of 2)

  • Organs – Groups of tissues that work together – single structures
    • Examples: Brain, heart, uterus (occurring in pairs: Eyes, lungs, kidneys)
  • Systems – Groups of organs – involved in a common set of activities
    • Example: Digestive system obtaining and digesting food and absorbing nutrients

Health and Disease

  • Health — a state of normal anatomy and physiology
  • Disease — the result when structures or functions of the body become abnormal

Homeostasis

  • Maintenance of dynamic equilibrium
  • Responsibility of the entire body
  • All physiological processes maintain the body’s balance in the various:
    • Structures
    • Functions
    • Properties
  • Makes life possible

Key Terms (Glossary)

  • Key Terms (1 of 5)

    • adipose
    • anatomy
    • anterior
    • barrel
    • bilateral symmetry
    • brisket
    • cannon
    • cardiac muscle
    • carpus
    • caudal
    • connective tissue
    • cranial
    • cranium
    • deep
    • digestive system
    • distal
    • dorsal
    • dorsal body cavity
    • dorsal plane
    • epithelial tissue
    • equilibrium
    • external
    • fetlock
    • fight-or-flight system
    • flank
    • gastrointestinal (GI) tract
    • gross anatomy
    • health
    • hock
    • homeostasis
    • inferior
    • inflammation
    • internal
    • knee - carpus of hoofed animals
    • lateral
    • macroscopic anatomy
    • medial
    • median plane
    • microscopic anatomy
    • muscle tissue
    • nervous tissue
    • organ
    • palmar
    • parietal layer
    • pastern
    • physiology
    • plane of reference
    • plantar

  • Key Terms (2 of 5)

    • pleura
    • poll
    • posterior
    • proximal
    • regional anatomy
    • rostral
    • sagittal plane
    • skeletal muscle
    • smooth muscle
    • spinal canal
    • stifle
    • superficial
    • superior
    • system
    • systematic anatomy
    • tailhead
    • tarsus
    • thorax
    • tissue
    • transverse plane
    • ventral
    • ventral body cavity
    • viscera
    • visceral layer
    • withers
    • xiphoid process

  • Key Terms (3 of 5)

    • neck
    • non-protein nitrogen compound (NPN compound)
    • omnivore
    • palate
    • parietal cell
    • pepsin
    • peptidase
    • peristalsis
    • plication
    • polysaccharide
    • prehension
    • premolar
    • procarboxypeptidase
    • proelastase
    • proenzyme (zymogen)
    • proteolytic enzyme
    • pyloric antrum
    • pyloric sphincter
    • radicular
    • hypsodont
    • reticulorumen
    • reticulum
    • root
    • rumen

  • Key Terms (4 of 5)

    • ruminant
    • rumination
    • saliva
    • salivary gland
    • secretin
    • segmentation
    • submucosa
    • submucosal plexus (Meissner’s plexus)
    • sucrase
    • temporomandibular joint
    • Triadan System
    • trypsin
    • urobilinogen
    • villi
    • volatile fatty acid

  • Key Terms (5 of 5)

    • (continued terms from page 20 as listed): ruminant (if repeating), rumination, saliva, salivary gland, secretin, segmentation, submucosa, submucosal plexus (Meissner’s plexus), sucrase, temporomandibular joint, Triadan System, trypsin, urobilinogen, villi, volatile fatty acid