Anatomy 1: lecture 2
Anatomy - DMD-701 Lecture 2 Overview
Part 2 - An Overview of Body Systems
This section covers various body systems studied in gross anatomy, specifically:
Skeletal System
Muscular System
Cardiovascular System
Lymphatic System
Nervous System
Digestive System
Respiratory System
Urinary System
Reproductive System
The Skeletal System
The skeletal system serves as the body's framework.
Composed of bones, cartilage, ligaments, and tendons.
Functions of the skeletal system:
Support and protection of vital organs.
Enables movement.
Stores minerals.
Produces blood cells.
The human skeleton is divided into:
Axial Skeleton: Comprising the skull, vertebral column, ribs, and sternum, forming the body's central axis.
Appendicular Skeleton: Including the limb bones (arms and legs) and girdles (pelvic and pectoral) that attach limbs to the axial skeleton.
Skeletal System - Main Components
Bones:
The adult human body contains 206 bones, classified by shape:
Long
Short
Flat
Sesamoid
Irregular
Bones contain both compact and spongy tissue.
Cartilage:
A flexible connective tissue that cushions joints and provides support in places like the nose and ears.
Ligaments:
Strong, fibrous tissues that connect bones to each other, stabilizing joints.
Tendons:
Strong, fibrous tissues that connect muscles to bones, enabling movement.
Joints:
Areas where two or more bones meet, allowing for various types of movement.
Skin and Fascia
Skin:
The largest organ in the body, made up of two main layers:
Epidermis: Outer layer; avascular and varies in thickness.
Dermis: Dense connective tissue layer beneath the epidermis.
Functions:
Acts as a mechanical barrier and regulates permeability.
Serves as a sensory and thermoregulatory organ.
Initiates primary immune responses.
Fascia:
Connective tissue varying in fat content that separates, supports, and interconnects organs and structures.
Functions:
Enables movement between structures.
Facilitates the transit of vessels and nerves.
Types of fascia:
Superficial Fascia: Lies just deep to the dermis and is attached to the skin.
Deep Fascia: Covers deeper regions of the body.
The Muscular System
Comprised of three types of muscle tissue:
Skeletal Muscle:
Responsible for voluntary movements and posture, consciously controlled.
Cardiac Muscle:
Found in the heart, responsible for pumping blood.
Smooth Muscle:
Located in the walls of internal organs and blood vessels, controlling involuntary movements like digestion.
Muscle Types
Skeletal Muscle:
Muscles we consciously control (e.g., arms, legs).
Attached to bones via tendons for movement and posture maintenance.
Cardiac Muscle:
Unique to the heart, essential for blood circulation.
Smooth Muscle:
Involuntary muscles found in the stomach, intestines, and blood vessels; regulate body functions.
The Cardiovascular System
Also known as the circulatory system, responsible for blood transport throughout the body.
Key components:
Heart: Acts as a muscular pump.
Blood Vessels: Including arteries, veins, and capillaries, serve as conduits for blood flow.
Blood: The fluid circulating in these vessels.
Functions:
Delivers oxygen and nutrients.
Removes waste products.
The Cardiovascular System - The Heart
A muscular organ with four chambers:
Two atria (right and left) and two ventricles (right and left).
Blood flow pattern:
Passes through valves for one-way flow.
The Cardiovascular System - Blood Vessels
Types of blood vessels:
Arteries:
Carry oxygenated blood away from the heart, except pulmonary arteries (deoxygenated blood to lungs).
Veins:
Transport deoxygenated blood to the heart, except pulmonary veins (oxygenated blood to heart).
Capillaries:
Connect arteries and veins; facilitate exchange between blood and body tissues.
The Cardiovascular System - Blood
Composed of plasma and formed elements:
Red blood cells (carry oxygen and carbon dioxide).
White blood cells (immune response).
Platelets (blood clotting).
Average human body contains 5 liters (1.3 gallons) of blood.
The Lymphatic System
Functions to:
Maintain fluid balance in the body.
Defend the body against infection.
Assist in fat absorption and removal of cell debris.
Structure:
Network of channels that connect to larger vessels, joining with veins at the neck's root.
The Nervous System
Functions as an intricate communication network; structural and functional divisions:
Structural Division:
Central Nervous System (CNS): Brain and spinal cord.
Peripheral Nervous System (PNS): Nerves outside CNS.
Functional Division:
Somatic: Innervates skin and skeletal muscle.
Visceral: Innervates organs, smooth muscle, and glands.
Cranial Nerves
List of cranial nerves:
I. Olfactory
II. Optic
III. Oculomotor
IV. Trochlear
V. Trigeminal
VI. Abducens
VII. Facial
VIII. Vestibulocochlear
IX. Glossopharyngeal
X. Vagus
XI. Accessory
XII. Hypoglossal
The Digestive System
Key processes involved:
Ingestion: Taking food into the body.
Digestion: Breaking food into small molecules.
Absorption: Nutrients absorbed into the bloodstream.
Excretion: Removal of waste products.
Organs of the Digestive System and Their Functions
G.I. Tract:
Mouth: Chews food, mixes with saliva.
Esophagus: Tube carrying food to the stomach.
Stomach: Stores and breaks down food with juices.
Small intestine: Main site of nutrient absorption.
Large intestine: Absorbs water and electrolytes; forms feces.
Rectum: Stores feces before elimination.
Anus: Exit point for feces.
Accessory Organs:
Liver: Produces bile to digest fats.
Gallbladder: Stores and releases bile into the small intestine.
Pancreas: Produces enzymes breaking down carbohydrates, proteins, and fats.
The Respiratory System
Responsible for oxygen intake and carbon dioxide expulsion.
Key components:
Nose
Mouth
Pharynx (throat)
Larynx (voice box)
Trachea (windpipe)
Bronchi
Lungs
Diaphragm
Organs of the Respiratory System and Their Functions
Nose and Mouth: Entry points for air.
Pharynx: Dual passageway for air and food.
Larynx: Contains vocal cords and directs air into the trachea.
Trachea: Tube conveying air to bronchi.
Bronchi: Split into two tubes for each lung.
Lungs: Main respiratory organs for gas exchange.
Diaphragm: Muscle aiding breathing.
Bronchioles: Smaller branches leading to alveoli.
Alveoli: Tiny air sacs for gas exchange.
The Urinary System
Also known as the renal system, responsible for filtering blood and producing urine.
Components:
Kidneys: Filter waste and excess water producing urine.
Ureters: Tubes carrying urine from kidneys to bladder.
Bladder: Stores urine until release.
Urethra: Carries urine to the outside during urination.
The Reproductive System
Collection of organs and structures for offspring production.
Divided into primary reproductive organs (gonads) and secondary reproductive organs (ducts, glands, external genitalia).
The Female Reproductive System
Ovaries: Produce eggs and female hormones (estrogen, progesterone).
Fallopian tubes: Connect ovaries to the uterus, site of fertilization.
Uterus: Where fertilized eggs implant and fetal development occurs.
Vagina: Canal connecting uterus to external body.
Vulva: External female genitalia.
The Male Reproductive System
Testes: Produce sperm and testosterone.
Epididymis: Stores mature sperm.
Vas deferens: Transports sperm to ejaculatory ducts.
Ejaculatory ducts: Connect vas deferens to urethra.
Urethra: Carries urine and semen out of the body.
Penis: External organ for intercourse and urination.
Scrotum: Pouch regulating temperature of the testes.
Laboratory Sessions Information
Location: DeBusk College of Osteopathic Medicine (DCOM)
Address: 9537 Cogdill Dr. Knoxville, TN 37932
Class divided into two groups (A and B).
Laboratory sessions: Every Wednesday (except August 27th).
Group A: Cadaver dissection at 8 a.m.
Group B: Cadaver dissection at 10 a.m.
Laboratory Introduction
First session: Introductory orientation at the cadaver lab.
Group meet times:
Group A: 7:50 a.m.
Group B: 9:50 a.m.
DCOM Anatomy Laboratory Attire
Closed-toe shoes required.
Locker bag and old scrubs for lab work.
No food or drink permitted in lab.
No personal items allowed in lab.
Safety goggles required.
Masks and gloves will be provided by school.
Always maintain respect in lab.
Important Note
DO NOT BE LATE TO THE LABORATORY SESSIONS.