Human Anatomy Lecture Notes PDF

1 ADML 122 Anatomy/Gross anatomy and histology BMD 209/BMS121 Human Anatomy This Unit covers CLO # 1 List the major body systems and identify the organs within each system, and Identify major organ structures as well as their histology....

1 ADML 122 Anatomy/Gross anatomy and histology BMD 209/BMS121 Human Anatomy This Unit covers CLO # 1 List the major body systems and identify the organs within each system, and Identify major organ structures as well as their histology. Dr.Sameh Fawzy Elsonbaty 1  OBJECTIVES Organization of the Body  The Human Body: An Orientation October 15, 2024 Dr.Sameh Fawzy Elsonbaty 2 Human Body Systems  Skeletal System Functions: 1. Provides shape & support 2. Helps you move 3. Protects organs 4. Produces blood cells 5. Stores certain materials  Skeletal System Protects internal organs: – Skull … protects the brain – Ribs … protect the heart & lungs – Vertebrae … protects the spinal cord – Femur … produces blood cells in the leg – Humerus … produces blood cells in the arm Organs of the Skeletal System Bones Cartilage – Connective tissue that is more flexible than bone – Ex: nose, tops of ears, ends of bones Ligaments – Hold bones together to form joints  Bone Marrow Marrow – soft connective tissue found in spaces in bone – Red marrow Produces the body’s blood cells – Yellow marrow Stores fat (energy reserve)  Muscular System Some functions: 1. Helps the body move 2. Moves food through the digestive system 3. Keeps the heart beating  Muscle Action Involuntary muscle – Muscles not under your conscious control Ex: muscles used for breathing & digesting food Voluntary muscles – Muscles that are under your conscious control Ex: Smiling, turning the pages in a book, walking to class  3 Types of Muscle Tissue Skeletal – Attached to bones & move bones using tendons Connective tissue attaching muscles to bones – Striated, or banded – Voluntary Smooth – Inside many internal organs – Involuntary – Ex: Stomach Cardiac – Found only in the heart – Involuntary – Never gets tired (unlike skeletal muscles)  How do muscles work? Muscles move by contracting, or becoming shorter Must work in pairs – One contracts, the other returns to its original length  Integumentary System (Skin) Functions: 1. Covers and protects the body to prevent water loss and keep out foreign particles. 2. Keeps you in touch with the environment (nerve endings) 3. Regulates your body temperature 4. Gets rid of wastes (sweat/perspiration)  Layers of the Skin Epidermis – Outermost layer – No nerves or blood vessels – Surface is made of dead cells (provide protection) Dermis – Lower layer of the skin – Contains nerves, blood vessels, sweat glands, hairs & oil glands Nervous System Functions: 1. Receives information about what is happening inside & outside of the body. 2. Directs the way your body responds to this information. (Remember stimulus and response?). 3. Helps maintain homeostasis.  Organs of the Nervous System Brain Nerves (neurons – nerve cells) Spinal Cord  Central Nervous System Brain - controls most functions in the body – Cerebrum Interprets input from the senses Controls movement of skeletal muscles Complex mental processes (learning) – Cerebellum Coordinates muscle actions & balance – Brainstem (medulla) Controls involuntary actions (ex: breathing) Spinal cord - link between brain &  Peripheral Nervous System Neurons – nerve cell that is specialized to transfer messages in the form of fast-moving electrical energy – electrical messages are called impulses Peripheral Nervous System Path of nerve impulse: sensory neuron spinal cord brain spinal cord motor neuron Video Clip: Senses & the Nervous S ystem  Respiratory System Why the body needs oxygen…  Respiratory System Function: – Moves oxygen from the outside environment into the body. – It also removes carbon dioxide and water from the body.  Path of Air into the Body Path of air into the body: nose pharynx trachea bronchi alveoli  How you breathe: Diaphragm – large dome-shaped muscle used in breathing. Structure of the Lungs Transfer Between the Lungs and the Blood Circulatory System (aka Cardiovascular System) Function: Carries needed substances to cells and carries wastes away from cells.  Organs Heart – Hollow, muscular organ that pumps blood throughout the body. Path of Blood Through the Heart  Organs – Blood Vessels Arteries – Blood vessel that carries oxygen-rich blood away from the heart and to the body parts. Capillaries – Small blood vessels where materials are exchanged between the blood and the body’s cells (oxygen & carbon dioxide) Veins – Carries oxygen-poor blood (w/carbon dioxide) back to the heart (to be Flow of Blood Through the Body Blood Vessels  Blood Blood is made of 4 components (parts): 1.Plasma – liquid part of blood 2.Red blood cells – take up oxygen in the lungs and deliver it to cells 3.White blood cells – the body’s disease fighters (part of immune system) 4.Platelets – cell fragments used in forming blood clots (that make  Roles of Organs Mouth – mechanical & chemical digestion starts here – Mechanical – physically breaking down food (teeth) – Chemical – breakdown of molecules of food (saliva) Esophagus – muscular tube connecting the mouth to the stomach – Peristalsis (muscle contraction) moves the food  Roles of Organs Stomach – Most mechanical digestion takes place – Some chemical with the help of digestive juices (enzymes & acids) Small Intestine – Most of the chemical digestion takes place – Absorption of nutrients from digested food into the bloodstream  Roles of Organs Large Intestine – Water is absorbed into the bloodstream – Remaining material is readied for elimination from the body Rectum – Waste material is compressed into solid form Path of food through Digestive System mouth esophagus stomach small intestine large intestine rectum eliminated from body  Excretory System Function: – Collects wastes produced by cells and removes the wastes from the body.  Organs Kidneys – Eliminate urea, excess water, & some other waste materials – Filter wastes from the blood – Produce urine  Organs Anus – Removes solid wastes from digestive system Lungs – Remove carbon dioxide produced during cellular respiration Skin – Removes perspiration (dissolved waste materials)  Immune System Function: 1. Provides a barrier against pathogens (disease causing agents). 2. Defends the body against pathogens. First line of defense: barrier Second line of defense: inflammatory response Third line of defense: immune system targets specific pathogens