Anatomy and Physiology for Veterinary Technicians

Anatomy

Deals with the form and structure of the body and its parts. A basic understanding is necessary to understand physiology

Physiology

Deals with the functions of the body and its parts. Physiology includes biophysical and biochemical processes. A basic understanding is necessary to understand veterinary technology

Cells

Basic functional units with much variation

Tissues

Groups of specialized cells of similar types or functions that cooperate to support the life of a complex organism as a whole. There are four types: Epithelial, Connective, Muscle, Nervous

Organs

Groups of tissues that work together for common purposes

Systems

Groups of organs involved in a common set of activities. This is the most complex level of body organization

Health

A state of normal anatomy and physiology. Disease results when the structures and functions of the body become abnormal

Homeostasis

The maintenance of a dynamic equilibrium in the body. It means all body systems working together. The body constantly adjusts to internal or external changes to try to maintain balance

Dynamic

Activity, energy, and work

Equilibrium

Balance

Matter

Anything that occupies space and has mass. Can exist as a gas, liquid, or solid. Composed of elements

Elements

Nitrogen, oxygen, hydrogen, and carbon make up 96% of all matter found in living organisms. Major in the animal body: Oxygen (O), Carbon (C), Hydrogen (H), Nitrogen (N). Minor elements in the animal body: Calcium (Ca), Phosphorus (P), Potassium (K), Sulfur (S), Sodium (Na), Chlorine (Cl), Magnesium (Mg).

Atoms

The smallest unit of an element that retains its unique properties. Composed of subatomic particles: Protons (positive charge), Neutrons (neutral), Electrons (negative charge).

Ions

An atom that has lost or gained an electrons, giving it a positive or negative charge. Indicated by + or -

Cation

Ion with a positive charge

Anion

Ion with a negative charge

Electron Shell

Atoms form bonds by sharing electrons. Atoms with exactly 2 or 8 electrons in the outermost are very stable and do not bond easily. Atoms with fewer than 2 or 8 are less stable and bond more easily to form molecules

Molecule

Formed when two or more atoms of different elements are joined. the smallest unit of a compound that retains the properties of that compound.

Isotopes

An atom with a different number of neutrons than normal. Radioactive can be used for treating cancer disease

Covalent

Atoms share electrons

Polarity

In some covalent bonds, shared electrons spend more time near one atom, creating slight positive and negative charges within the molecule

Ionic

Electrons are transferred from one atom to another

Hydrogen

A specific type of weak ionic bond

Chemical Reactions

Involve the formation or breaking of chemical bonds. They require energy or release energy. Three types

Synthesis

Building up

Decomposition

Breaking down

Exchange Reactions

Even exchange

Organic Compounds

Contain hydrocarbon groups and are usually covalently bonded. Contain hydrocarbon groups and often a functional group. Many are macromolecules. Four types. Carbon has 4 electrons in its outer shell and forms covalent bonds to complete it

Inorganic Compounds

Do not contain hydrocarbon groups and often have ionic bonding

Water

Ideal transport medium. High heat capacity and high heat of vaporization. Used for lubricant. Universal solvent

Salts

Mineral compounds with ionic bonds. Principle form of minerals entering and stored in the body. Ionize immediately when added to water. In ionized form, they are known as electrolytes, substances that can transmit an electrical charge

Acids

Ionically bonded substances that release hydrogen ions in water

Bases

Ionically bonded substances that release hydroxl ions in water

Buffers

Weak acids and bases that do not completely ionize in water

pH Scale

Measures acidity and alkalinity

Carbohydrates

Provide over half the energy for metabolic functions, storage of energy, part of cellular structures, backbone, of DNA and RNA

Lipids

Contain C, H, and O, but lower in O than carbohydrates. Four classes. Energy use, storage in fat, component of some hormones, important role in cell structure

Proteins

Most abundant organic molecules in the body. Made of amino acids. 20 different amino acids used in the body. Central carbon, hydrogen, amino croup, carboxyl group, and a side chain. The specific combination of amino acids is determined by DNA. Animo acids link via peptide bonds. Primary, Secondary, tertiary, quintenary. Chemical reactions, transport, growth, regulation, immunity, structural framework, muscular function

Nucleaic Acids

Largest molecules in the body. Made of carbon, oxygen, hydrogen, nitrogen, and phosphorus. Two classes

DNA

Double helix, contains genetic instructions

RNA

Single helix, important for protein synthesis

ATP

Main energy source in the cell. Energy from food is stored in the phosphate bonds. An RNA nucleotide: adenosine + 3 phosphates. Made from ADP + one more phosphate. Energy is released when the third phosphate bond is broken, yielding ADP + energy. Is continuously recycled

Prokaryotes

Cells without a nucleus

Eukaryote

Cells with a nucleus

Cell Membrane

Separates the cell from its environment. Regulates substance passage. Made of a double layer of phospholipids with proteins and other molecules. Phospholipids have hydrophilic heads facing outwards and hydrophobic tails meeting in the center. Cholesterol stabilizes. Globular proteins are scattered through

Nucleus

The control center containing genetic information. Contains DNA and RNA

Cytoplasm

Everything inside the cell membrane except the nucleus material. Contains proteins, electrolytes, metabolites, cytoskeleton

Organelles Membrane

Bound structures in cytoplasm with specialized functions

Mitochondria

Produce most cellular energy, site of cellular respiration

Ribosomes

Protein synthesis. Free ribosomes make protein for intracellular use. Ribosomes on ER make protein for membrane or export

Endoplasmic Reticulum (ER)

Series of flattened tubes. Rough has ribosomes. Smooth synthesizes and stores lipids

Golgi Apparatus

Protein packaging +/- modification

Lysosomes

Digestion and breakdown

Peroxisomes

Detoxification

Centrioles

Involved in cell division

Cilia

Numerous, short, on outer surface of some cells

Flagella

Single, long, undulates for propulsion

Intercellular Fluid

Inside the cell

Extracellular Fluid

Outside the cell

Selectively Permeable

Select which substances to allow passage

Concentration

How many molecules are in a solution

Concentration Gradient

The spectrum between areas of high and low concentration

Diffusion

Movement of molecules in fluid/gas from high concentration to low concentration

Facilitated Diffusion

Molecules pass with assistance from a carrier protein in the membrane

Osmosis

Movement of water through a semi-permeable membrane. Moves from an area of low solute concentration to high solute concentration

Tonicity

Describes extracellular fluid concentration relative to intracellular fluid

Osmotic Pressure

The force of water moving across a membrane due to concentration difference

Oncotic Pressure

Pulling pressure keeping fluid in the bloodstream by osmosis

Filtration

Based on a pressure gradient . Liquid and some dissolved solids are pushed through a membrane if pressure is greater on one side

Hydrostatic Pressure

The force that pushes liquid

ATP

Made by mitochondria. Needed when molecules are not lipid soluble, too large, or on the wrong side of the concentration gradient

Active Transport

Relies on a carrier protein with a specific binding site, and uses energy for transport

Cytosis

Mechanism for bringing substances into or getting rid of substances from the cell

Endocytosis

Engulfment of substances outside the cell to bring them into the cell

Exocytosis

Material exiting the cell

Resting Membrane Potential

Refers to changes in the distribution of the charged particles on either side of the cell membrane

Mitosis

Cell divides into 2 equal parts. Form daughter cells

Interphase

The period between cell division

DNA Replication

Cell Division. Inheritance. Repair and growth

Mitotic Phase

Cell is actively dividing. Four stages

Prophase

This is the initial stage where chromosomes condense and become visible

Prometaphase

The nuclear envelope is completely disassembled, and chromosomes are free in the cell

Metaphase

Chromosomes align at the center of the cell, forming the metaphase plate

Anaphase

Sister chromatids separate and are pulled to opposite poles of the cell

Telophase

The nuclear envelope reforms around each set of chromosomes, and the cell prepares to divide

Transcription

Formulation of mRNA. mRNA-a carrier molecule that transports genetic information from the nucleus to the cytoplasm to make a protein.

Translation

The process of building a new protein using the information from the mRNA molecule

Mutation

A genetic error

Epithelial

A special group of tissues which are designed to cover the external surfaces and line the internal surfaces of an animal’s body. Each cell has a apical surface and a basal surface. Apical surface faces the lumen or outside of the organ. Basal surface faces the basal lamina and blood vessels. Lateral surfaces are connected to neighboring cells by junctional complexes. Cells are avascular. Most cells are innervated. Simple or stratified layers of cells. The nature of the surface varies with its role at any particular location. Protects, absorbs, filters, sensory, secretes, excretes

Glandular Epithelium

Groups of cells that manufacture and discharge a secretion. Glands

Exocrine Glands

Do possess ducts. Secretions discharged directly into local areas. Unicellular exocrine gland. Most are multicellular

Endocrine Glands

Produce & secrete regulatory chemicals called hormones to entire body via bloodstream. No ducts or tubules

Connective Tissue

Metabolic and structural connections between cells and other tissues. Protects organs. Shock absorption. Insulates the body. Energy reserve. Frame to support the body. Transport of substances from one part of the body to another. Healing process after injury. Control over invading pathogens. Collagenous fibers. Tendons and ligaments. Reticular fibers. Provide support for highly cellular organs. Elastic fibers. Found in spaces between vertebrae and in areas of the body that require stretching. Fixed cells that produce the CT matrix. Fibroblasts, adipocytes, osteoblasts, chondroblasts

Cartilage

Found in joints and in the ear, nose, and vocal cords, Forms a framework on which bone is formed. No innervation; avascular. Chondrocytes. Matrix: Ground substance: gel of chondroitin sulfate, hyaluronic acid, and chondronectin

Bone

Matrix: a combination of organic collagen fibers and inorganic calcium salts. Well-vascularized. Haversian canal contains both avascular and nerve supply

Blood

Ground substance: plasma. Fibrous component: protein. Cells: Erythrocytes, Leukocytes, Thrombocytes

Membranes

Thin, protective layers of tissue. Epithelial sheet bound to underlying layer of connective tissue

Mucous Membranes

Line and protect organs that have connection with outside environment. Decrease friction Assist with passage of food or waste

Serous Membrane

Line closed body cavities and the organs within those cavities. Produce transudate which moistens surfaces

Cutaneous Membranes

Produce keratin that makes skin waterproof and prevents drying