Body Organisation Study Notes PDF

Learning Objectives 1. Define anatomy and physiology 2. List the different levels of structural organisation in the body Anatomy & Physiology Anatomy: the study of structure • Gross or macroscopic (regional, surface, systemic anatomy) • Microscopic (cytology and histology) • Developmental (embryol...

Learning Objectives 1. Define anatomy and physiology 2. List the different levels of structural organisation in the body Anatomy & Physiology Anatomy: the study of structure • Gross or macroscopic (regional, surface, systemic anatomy) • Microscopic (cytology and histology) • Developmental (embryology) Physiology: the study of function at many levels Subdivisions are based on organ systems • Renal or cardiovascular physiology Physiology Physiology focuses on the functions of the body Considers the operation of specific organ systems • Renal physiology (kidney function), Neurophysiology (nervous system function), Cardiovascular (heart and blood vessels function) • Also requires a knowledge of basic physical and chemical principles (e.g., electrical currents, pressure, and movement) Anatomy and physiology are inseparable • Function always reflects structure • What a structure can do depends on its specific form Learning Objectives 3. Name the organs contained within the following organ system and list the major function of each organ: • nervous system • cardiovascular system • endocrine system • respiratory system • renal system • digestive system • reproductive systems Integumentary System (Skin) Forms the external body covering Components: Skin, hair, nails, sweat, oil glands Functions: • Protects body • Helps regulate body temperature • Eliminates some wastes • Helps produce vitamin D • Detects sensations (pain, touch, hot, cold) Skeletal System Components: bones, joints and associated cartilages Functions: • Supports and protects body organs • Provides framework for muscles • Aids body movement • Site of blood cell formation • Stores minerals and lipids (fats) Bones Joint Muscular System Components: Skeletal muscle tissue, attached to bones, Tendons Functions: • Produces body movements • Stabilises body position (posture) • Generates heat • Allows manipulation of the environment, locomotion, and facial expression Nervous System Components: brain, spinal cord, nerves, special sense, organs (eye & ear) Functions: • Uses action potentials/nerve impulses to regulate body activities • Detects changes in the body’s internal and external environment • Interprets changes and responds by causing muscular contractions or glandular secretions Endocrine System Components: hormone producing cells and glands (e.g. pituitary gland, thyroid gland, pancreas) Functions: • Regulates body activities by releasing hormones • Hormones transported in blood from an endocrine gland to a target organ Cardiovascular System Components: blood, heart, blood vessels Functions: • The heart pumps blood • Blood carries oxygen and nutrients to cells and carbon dioxide and waste away from cells • Helps regulate acidity, water content and temperature • Blood components help defend against disease Lymphatic & Immune System Thoracic Red bone marrow duct Components: Lymphatic fluid and vessels, red marrow, spleen, thymus gland, lymph nodes, tonsils Functions: • Returns proteins and fluid to blood • Carrier lipids from GIT to blood • Sites of maturation of white blood cells (immunity) Thymus Lymphatic vessels Spleen Lymph nodes Respiratory System Components: Composed of the nasal cavity, pharynx, trachea, bronchi, and lungs Functions: • Transfers oxygen from inhaled air to blood and carbon dioxide from blood to exhaled air • Air flowing out of lungs through vocal cords produces sound Nasal cavity Pharynx Larynx Trachea Lung Bronchus Digestive System Components: mouth, salivary glands oesophagus, stomach, intestines, liver, gallbladder, pancreas, rectum, anus. Oral cavity Esophagus Functions: • Physical and chemical breakdown of food • Absorbs nutrients • Eliminates solid wastes Liver Stomach Small intestine Large intestine Rectum Anus Urinary System Components: kidneys, ureters, urinary bladder, and urethra Functions: • Produces, stores & eliminates urine • Eliminates nitrogenous wastes from the body • Regulates water, electrolyte & pH balance of the blood • Helps regulate red blood cell production Kidney Ureter Urinary bladder Urethra Male Reproductive System Mammary glands (in breasts) Components: Testis, scrotum, penis, Prostate seminal ducts and glands gland Function: Penis • Testis To produce offspring. Scrotum • Testes produce sperm & male sex hormone • Ducts & glands aid in the delivery of sperm to the female reproductive tract. Ovary Uterus Vagina Uterine tube Female Reproductive System Mammary glands (in breasts) Components: Ovaries, uterine tubes, Prostate uterus, vagina, mammary gland glands Function: Penis • Testis To produce offspring. • Ovaries produce eggs & female sex hormones. • Sites for fertilization & development of the fetus. • Mammary glands produce milk to nourish the newborn. Ovary Uterus Vagina Uterine tube Organ Systems Relationships Organ systems work cooperatively to perform necessary life functions 1. Nutrients are absorbed into the blood through the digestive system 2. oxygen is inhaled through the respiratory system 3. Nutrients and oxygen are distributed by the cardiovascular system to organs and tissues 4. Metabolic wastes are eliminated by the urinary and respiratory systems Necessary Life Functions • Metabolism: all the chemical reactions that occur in the body • Excretion: removal of wastes from the body • Responsiveness: body’s ability to detect and respond to changes in its internal or external environment • Movement: includes motion of the whole body, individual organs, single cells, tiny structures within cells • Reproduction: formation of new cells for growth, repair or replacement or to the production of a new individual • Growth: increase in size of a body part or of the organism • Differentiation: process a cell undergoes to develop from an unspecialised to a specialised state Survival Needs • Nutrients: chemical substances used for energy and cell building • Oxygen: needed for metabolic reactions • Water: provides the necessary environment for chemical reactions • Maintaining normal body temperature: necessary for chemical reactions to occur at life-sustaining rates • Atmospheric pressure: required for proper breathing and gas exchange in the lungs Learning Objectives 4. Describe the anatomical position. 5. Use correct anatomical terminology to describe body directions, body regions, and body planes or sections. 6. Locate and name the major body cavities and their subdivisions. 7. Name the four quadrants or nine regions of the abdominopelvic cavity and list the organs they contain. Anatomical Position Standard anatomical body position: • Body erect • Feet slightly apart • Palms facing forward Table 1.1 Table 1.1 Table 1.1 Table 1.1 Table 1.1 Regional Terms Two major divisions of the body: 1. Axial skeleton (yellow) • Skull • Vertebrae • Sternum & ribs • Sacrum 2. • • • • Appendicular skeleton (grey) Pectoral girdle Upper extremity Pelvic girdle Lower extremity Body Planes 1. Sagittal plane: divides body vertically into right and left parts • Mid-sagittal (median) plane: lies on midline • Para-sagittal plane: not on midline 2. Frontal (coronal) plane: divides body vertically into anterior and posterior parts 3. Transverse (horizontal) plane: divides body horizontally into superior and inferior parts (cross section) Body Cavities Dorsal cavity: protects the nervous system Two subdivisions: • Cranial cavity (brain) • Vertebral cavity (spinal cord) Ventral cavity: houses the internal organs (viscera) Two subdivisions (separated by diaphragm): • Thoracic cavity (lungs and heart) • Abdominopelvic cavity (digestive, urinary and reproductive organs) Cranial cavity Cranial cavity Dorsal cavity Ventral cavity Vertebral cavity Dorsal cavity Thoracic cavity Vertebral cavity Thoracic cavity Ventral cavity Abdominopelvic cavity (a) Lateral view Dorsal cavity: protects the nervous system Two subdivisions: • Cranial cavity (encases brain) • Vertebral cavity (encases spinal cord) Abdominopelvic cavity (b) Anterior view Ventral cavity: houses the internal organs Two subdivisions, separated by diaphragm • Thoracic cavity • Abdominopelvic cavity Ventral Body Cavities Thoracic cavity subdivisions: • Two pleural cavities that each house a lung • Mediastinum contains the pericardial cavity, surrounds thoracic organs • Pericardial cavity encloses heart Dorsal body cavity Ventral body cavity Superior mediastinum Thoracic cavity Pleural cavity Pleural cavity Pericardial cavity Ventral body cavity Ventral Body Cavities Abdominopelvic cavity subdivisions: • Abdominal cavity: stomach, intestines, spleen, and liver • Pelvic cavity: urinary bladder, reproductive organs, and rectum Dorsal body cavity Ventral body cavity Ventral body cavity Abdominal cavity Pelvic cavity Abdominopelvic cavity Abdominopelvic Regions Abdominopelvic Quadrants