Directional Terminology Notes

Page 1: Directional Terminology

• Introduction to the concept of directional terminology in anatomy.

Page 2: Learning Objectives

• Memorization: Understand definitions of directional terminologies.

• Application: Learn to apply these terminologies to anatomical structures and surfaces.

• Regional Terminologies: Familiarize with regional terminologies in anatomy.

Page 3: Importance of Directional Terminology

• Communication: Essential for clear communication in anatomical contexts.

Page 4: Overview of Terminology

• Categories:

  • Anatomical Directions

  • Anatomical Planes

  • Regional Terminology

Page 5: Anatomical Directions

• Cranial: Towards the head

• Proximal: Closer to the body (only on extremities)

• Superior: Above or higher

• Caudal: Towards the tail

• Distal: Further from the body (only on extremities)

• Inferior: Below or lower

• Rostral: Towards the nose (head region)

• Palmar: Palm surface of the forelimb (distal portion of the carpus)

• Posterior: Towards the back

• Plantar: Sole surface of the hindlimb (distal portion of the tarsus)

• Anterior: Towards the front

• Dorsal: Towards the back

• Ventral: Towards the belly

• Medial: Towards the mid-line

• Lateral: Away from the mid-line

Page 30: Detailed Anatomical Directions

• Cranial: Towards the head

• Caudal: Towards the tail

• Rostral: Towards the nose

• Dorsal: Towards the back

• Ventral: Towards the belly

• Proximal: Towards the body (extremities)

• Distal: Away from the body (extremities)

• Medial: Towards the mid-line

• Lateral: Away from the mid-line

• Palmar: Palm surface (forelimb)

• Plantar: Sole surface (hindlimb)

• Superficial: Towards the surface

• Deep: Towards the center

• External: Towards the surface

• Internal: Towards the center

Page 31-32: Human Anatomical Directions

• Superior: Towards the head

• Inferior: Towards the feet

• Anterior: Towards the front

• Posterior: Towards the back

• Veterinary Equivalents: Understanding differences in terminology between humans and animals.

Page 33: Advanced Directional Terminologies

• Unilateral: On one side

• Bilateral: On both sides

• Ipsilateral: Same side

• Contralateral: Opposite side

Page 35: Anatomical Planes

• Dorsal Plane: Separates dorsal and ventral

• Median Plane (Midsagittal): Separates left and right equally

• Sagittal Plane: Separates left and right unequally

• Transverse Plane: Separates cranial and caudal; on limbs, separates proximal and distal

Page 38-40: Format of Anatomic Communication

• Example: "The sternum is cranial to the pelvis."

• Clinical applications of directional terminology in practice.

Page 49-56: Regional Terminology

• Common Terms:

  • Withers: Top of the shoulder

  • Barrel: Body of the animal

  • Poll: Top of the head

  • Muzzle: Front part of the face

  • Flank: Side of the body

  • Brisket: Front of the chest

  • Knee: Carpus in animals

  • Stifle: Equivalent to the human knee

  • Hock: Tarsus (ankle region)

  • Pastern: Area between the fetlock and the hoof

  • Fetlock: Joint between the cannon bone and the pastern

Page 57-59: VTNE Sample Questions

• Understanding the application of anatomical terminology in veterinary contexts through sample questions.

CHEMICAL BASIS

Slide 4

Matter - Anything that occupies space and has mass. It can be a solid, liquid, or gas

Mass - Amount of matter a substance contains

Weight - Force of gravity acting on an object with mass

Volume - How much space an object takes up

Slide 5

All matter can be made up of one or more elements, but each element will only have one type of atom.

Slide 6

List of common elements you should recognize

Na - Sodium

K - Potassium

Cl - Chlorine

H - Hydrogen

C - Carbon

O - Oxygen

Mg - Magnesium

Hg - Mercury

Fe - Iron

N - Nitrogen Ca - Calcium

Slide 8

Atom - The smallest unit of matter that retains the properties of a single element

• Atoms consists of neutrons, protons (+), and electrons (-)

Slide 9

Ion - Any particle with a positive or negative charge due to the gain or loss of electrons

Cation - positive-charged atom

Anion - negative-charged atom

Slide 11

• Electrons orbit the atom in a section referred to as 'shells'. Electrons will always try to fill the inner shells first.

• The outer shell always wants to be fully 'satisfied' by being either completely filled or entirely empty.

Slide 12

Ionic Bond—When an atom transfers an electron to another, this forms an ionic bond. One atom loses an electron, and the other gains an electron.

Slide 15

Covalent Bond - When an atom shares electrons with another atom. Both atoms are gaining electrons, and neither is losing electrons.

Slide 16

Polar - Having two opposite charges.

Polar Covalent Bond - A covalent bond with an uneven distribution of electrons.

This makes one side positive and one side negative.

Non-polar Covalent Bond - A covalent bond with an even distribution of electrons.

This makes both sides (usually) negative.

Slide 17

• Because water molecules form polar covalent bonds, they have a tendency to stick to each other. This is the concept of cohesion and adhesion.

Slide 20

• The two main factors that influence the formation of chemical reactions are concentration and temperature.

Slide 21

Synthetic Reactions - Occur when two or more atoms combine to form a new and larger molecule. This means that several smaller compounds are combined to form a larger compound.

Slide 22

Decomposition Reaction - This occurs when two or more atoms combine to form a new and larger molecule. This means that a larger compound is breaking down into several smaller compounds.

Slide 24

Exchange Reaction - A combination of decomposition and synthetic reactions. This involves two or more atoms that exchange their components without becoming larger or smaller.

Slide 27

Organic compounds are:

• Usually large and complex molecules

• Always contains carbon

• Contains C-C or C-H bonds

• Usually bonded via covalent bonds

• E.g. carbohydrates, lipids, proteins, nucleic acids, and ATP.

Inorganic compounds are:

• Smaller molecules

• Lacks carbon (rare)

• Does not have C-C or C-H bonds

• Usually bonded via ionic bonds

• E.g. water, oxygen, carbon dioxide, many salts, acids, and bases

Slide 28

Solute - any substance that dissolves within another substance

Solvent - any liquid that dissolves a solute

Solution - the end-product of a solute dissolved in a solvent.

Slide 30

• Water is the universal solvent

Slide 31

Water-soluble - The ability to readily dissolve in the presence of water.

Lipid-soluble - The ability to readily dissolve in the presence of lipids.

Slide 32

True solutions - Smaller solute size will not settle over time.

Colloidal solutions - Larger solutes than true solutions, but they still will not settle over time.

Suspension solutions: The largest solutes will settle over time, falling to the bottom of the container.

Slide 35

Acids:

• Will dissociate into one or more hydrogen ions (Ht)

• Will dissociate into one or more anions (negative ions)

• Are proton donors

Bases:

• Will dissociate into one or more hydroxide ions (OH-)

• Will dissociate into one or more cations (positive ions)

• Are proton acceptors

Slide 36

Salts:

• Will not dissociate into either hydrogen nor hydroxide

• Will dissociate into cations and anions

Slide 39

• The pH scale measures the acidity or alkalinity of a substance.

• 7.0 is a neutral pH.

• Any number higher than 7.0 is considered alkaline or basic.

• Any number lower than 7.0 is considered acidic.

• Normal blood pH is ~ 7.4

Slide 40

Buffers - Substances that maintain a neutral pH level and can neutralize acids and bases.

• Bicarbonate is the most important buffer of the body.

Slide 42

• The four basic organic compound groups are carbohydrates, lipids, proteins, and nucleic acids.

Slide 43

Monosaccharides - Building blocks of carbohydrates

Disaccharides - Formed by combining two monosaccharides

Polysaccharides - Formed by combining many monosaccharides

Slide 44

Hydrophobic - Insoluble in the presence of water. Also, it typically repels or is repelled by water.

Slide 45

Neutral fats (triglycerides) - A most common type of lipid in your blood. Has many functions that were not discussed specifically.

Slide 47

• Phospholipids have a hydrophilic head and a hydrophobic tail.

• Phospholipids make up the cell membrane.

• This membrane is selective and can control what passes through.

Slide 48

Steroids - Lipid compounds with a wide range of functions generally help most processes in the body.

Cholesterol - The most common steroid in the body and one of the most important.

Slide 49

Slide 51

• Enzymes are protein-based substances that activate and processed by using a lock and-key mechanism.

Slide 52

Slide 54+55

ATP (adenosine triphosphate) - The 'energy currency' of all living’. This is the equivalent of how electricity can power a device.

Tissues Overview

Page 1: Introduction to Tissues

• Types of Tissues: Epithelial, Connective, Muscle, Nervous

Page 2: Lecture and Lab Focus

• Lecture:

  • Characteristics of each tissue type

  • Classification of tissues

  • Basic functions of tissues

  • Locations of tissues

• Lab:

  • Identification based on physical characteristics

    • Types of cells

    • Types of fibers

    • Physical orientation

Page 3: Types of Tissues

• Epithelial: Covers surfaces, lines organs, forms glands

• Connective: Supports and binds organs, provides immunity

• Muscle: Generates force and movement

• Nervous: Initiates nerve impulses for coordination

Page 4-5: Epithelial Tissue Features

• Characteristics:

  • Closely packed cells with minimal space

  • Arranged in single or multiple layers

  • Apical and basal surfaces

  • Avascular

• Functions: Protection, absorption, secretion, excretion, lubrication

Page 6-7: Epithelial Tissue Structure

• Apical Surface: Faces lumen or outside body

• Basal Surface: Attached to basement membrane

• Classification:

  • Arrangement: Simple, Stratified, Pseudostratified

  • Shape: Squamous, Cuboidal, Columnar, Transitional

Page 8-10: Epithelial Cell Shapes

• Squamous: Flat, allows diffusion

• Cuboidal: Cube-shaped, involved in secretion/absorption

• Columnar: Tall, may have cilia/microvilli

• Transitional: Round, flexible, always stratified

Page 11-12: Naming Epithelial Tissues

• Naming Convention:

  1. Number of layers

  2. Cell shape

  3. Epithelial tissue or epithelium

• Examples: Simple Columnar Epithelial Tissue, Stratified Squamous Epithelial Tissue

Page 15: Surface Specializations

• Keratin: Provides rigidity and waterproofing

• Cilia: Hair-like structures aiding in movement

Page 16-22: Types of Epithelial Tissue

• Simple Squamous: Efficient transfer, found in blood vessels, lungs

• Simple Cuboidal: Lines tubules and glands, involved in secretion/absorption

• Non-ciliated Simple Columnar: Contains goblet cells, lines GI tract

• Ciliated Simple Columnar: Lines respiratory tract, aids in movement

• Stratified Squamous: Provides protection, keratinized/non-keratinized

• Stratified Cuboidal: Rare, found in sweat glands

• Stratified Columnar: Rare, found in urethra

• Pseudostratified Columnar: Lines respiratory tract, can be ciliated

• Transitional: Allows distension, found in bladder

Page 28-30: Glandular Epithelium

• Types:

  • Endocrine: Secretes into bloodstream

  • Exocrine: Secretes onto surfaces

• Goblet Cells: Secrete mucus, found in various tracts

Page 31-50: Connective Tissue

• Features:

  • Found under epithelial tissue, supports organs

  • Components: Cells, fibers, ground substance

  • Highly vascular

• Classification:

  • Loose Connective Tissue: Areolar, Adipose, Reticular

  • Dense Connective Tissue: Regular, Irregular, Elastic

  • Cartilage: Hyaline, Elastic, Fibrocartilage

  • Specialized: Blood, Bone

Page 32-38: Connective Tissue Components

• Fibroblast: Main cell type

• Chondrocyte: Cartilage cells in lacunae

• Fibers:

  • Collagen: Strong, pink-stained

  • Elastic: Flexible, dark pink/light purple

  • Reticular: Spider-web-like, dark purple/black

Page 38-48: Types of Connective Tissue

• Areolar Tissue: Supports organs, found in various locations

• Adipose Tissue: Stores fat, provides insulation

• Reticular Tissue: Filters organs, found in spleen/liver

• Dense Regular: Strong attachment, found in tendons/ligaments

• Dense Irregular: Provides strength, found in skin

• Elastic Tissue: Allows stretching, found in blood vessels

• Cartilage Types:

  • Elastic: High elasticity, found in epiglottis

  • Hyaline: Most common, found in joints

  • Fibrocartilage: Strong, found in intervertebral disks

Page 48-50: Bone and Blood

• Bone: Compact and spongy types, contains osteons

• Blood: Matrix is plasma, contains erythrocytes, leukocytes, thrombocytes

Page 51-57: Muscle Tissue

• Characteristics: Identified by striations and function

• Types:

  • Skeletal Muscle: Striated, voluntary

  • Smooth Muscle: Non-striated, involuntary

  • Cardiac Muscle: Striated with intercalated disks, involuntary

Integumentary System Overview

Page 1: Introduction

• Integumentary System: The body's outer covering.

Page 2: Components

• Includes:

  • Skin

  • Hair

  • Hooves

  • Claws

  • Skin-related glands

• Functions:

  1. Prevents desiccation

  2. Reduces threat of injury

  3. Thermoregulation

  4. Excretes water, salts, and other wastes

  5. Receives sensory information

  6. Synthesizes vitamin D (functions as an endocrine gland)

Page 3: Skin Layers

• Layers of the Cutaneous Integument (from superficial to deep):

  1. Epidermis

  2. Dermis

  3. Hypodermis (subcutaneous)

Page 4: Epidermis

• Characteristics:

  • Avascular (no blood vessels)

  • Composed of epithelial tissue

• Dead Epidermis:

  • Stratum corneum

  • Stratum lucidum

• Cell Types:

  • Keratinocytes

  • Melanocytes

  • Langerhans cells

  • Merkel cells

Page 5: Cells of the Epidermis

1. Keratinocytes: Produce keratin for protection.

2. Melanocytes: Produce melanin for UV protection.

3. Langerhans cells: Macrophages for immune support.

4. Merkel cells: Sensory cells for touch sensation.

Page 6: Layers of the Epidermis

• From Superficial to Deep:

  1. Stratum corneum

  2. Stratum lucidum

  3. Stratum granulosum

  4. Stratum spinosum

  5. Stratum basale

Page 7: Stratum Corneum

• Characteristics:

  • Thickest layer (20-30 layers of keratinized cells)

  • First line of defense

  • Continuously sheds

Page 8: Stratum Lucidum

• Characteristics:

  • Found only in thick skin (e.g., paw pads)

  • Clear due to loss of nucleus and organelles

Page 9: Stratum Granulosum

• Characteristics:

  • Keratin infiltration begins

  • Cells degenerate and lose organelles

  • Transition layer between active and dead cells

Page 10: Stratum Spinosum

• Characteristics:

  • Provides skin flexibility

  • Contains all four cell types

Page 11: Stratum Basale

• Characteristics:

  • Basement membrane of the epidermis

  • Contains stem cells for regeneration

  • Damage can impair skin cell regeneration

Page 12: Dermis

• Characteristics:

  • Composed of connective tissue

  • Vascular with nerve fibers, glands, and hair follicles

• Layers:

  1. Papillary dermis

  2. Reticular dermis

Page 13: Papillary Layer

• Characteristics:

  • Composed of areolar tissue

  • Forms dermal papillae for anchoring and reducing friction

Page 14: Reticular Layer

• Characteristics:

  • Composed of dense irregular connective tissue

  • Provides elasticity and strength

Page 15: Hypodermis (Subcutaneous)

• Characteristics:

  • Mainly adipose and areolar tissue

  • Provides thermal insulation and shock absorption

  • Highly vascular with nerve receptors

Page 16: Related Integumentary Structures

• Paw Pads:

  • Thick stratum corneum

  • Insulated with adipose tissue

  • Contains exocrine sweat glands in small animals

Page 17: Planum Nasale

• Characteristics:

  • Pigmented and hairless surface of the nose

  • Lacks stratum granulosum and stratum lucidum

Page 18: Skin Layering Types

• Types:

  • Thick: No epidermal layers absent (e.g., paw pads)

  • Standard: Stratum lucidum present

  • Thin: Stratum lucidum and granulosum absent (e.g., planum nasale)

Page 19: Hair and Glands

• Topics:

  • Types of hair

  • Hair follicle structure

  • Hair growth cycle

  • Skin glands

Page 20: Types of Hair

1. Primary Hair: Thicker, longer, slightly water-repellent.

2. Secondary Hair: Shorter, thinner, acts as undercoat.

3. Tactile Hair: Long, heavily innervated, acts as touch receptors (whiskers).

Page 21: Hair Follicle

• Characteristics:

  • Invagination in the epidermis for hair root

  • Can be simple or compound

  • Variability in dogs and cats based on breed

Page 22: Major Structures of the Hair Follicle

• Arrector Pili Muscle: Smooth muscle causing hair to stand up.

• Sebaceous Glands: Release sebum to moisturize hair and provide surface immunity.

Page 23: Glands of the Skin

• Sebaceous Glands: See previous slide.

• Eccrine Sweat Glands: Release substances onto skin (only in paw pads of small animals).

• Apocrine Sweat Glands: Release into hair follicles (found in external ear canal of small animals).

Page 24: Anal Sacs

• Location: At 4 and 8 o’clock positions of the anus.

• Characteristics:

  • Connected by a single duct

  • Secretes foul-smelling substances during defecation or when threatened.

Page 25: Tail Glands

• Location: Dorsal aspect of the tail.

• Characteristics:

  • Contains sebaceous and apocrine glands for animal identification.

Page 26: Cutaneous Pouches of Sheep

• Location: Infraorbital, interdigital, and inguinal regions.

• Characteristics:

  • Contains numerous sebaceous glands

  • Secretes lanolin used in cosmetics and ointments.