Introduction to Human Anatomy The Anatomical Position For, descriptions of body structures the body is assumed to be in a specific orientation, called the anatomical position Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position The subject is Facing forward Head level Eyes facing forward Feet flat on ground arms down the sides palms turned forward Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position While laying down: Prone Body facing down Supine Body is facing up Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position Anterior or Ventral Front of the body Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position Posterior or Dorsal Back of the body Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position Superior: Toward the top Inferior: Toward the bottom Neck is superior to the abdomen Thigh is inferior to the abdomen Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position Distal: Away from, farther from origin Proximal: Near, closer to the origin Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position Lateral away from the midline of body Medial toward the midline of body Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position Contralateral On the opposite side Ipsilateral On the same side Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position Tanveer Raza MD MS MBBS razajju3@yahoo.com The Anatomical Position Superficial: Towards the surface Deep: Towards the center Tanveer Raza MD MS MBBS razajju3@yahoo.com Anatomical Positions Anatomical planes Coronal plane Separates body into front and back half Sagittal plane Left and right halves Transverse plane Superior and inferior halves Tanveer Raza MD MS MBBS razajju3@yahoo.com Tanveer Raza MD MS MBBS razajju3@yahoo.com Body Cavities, Abdominopelvic Regions and Quadrants Structural Plan: The human body has certain general characteristics. Among the characteristics are a backbone, a tube within a tube organization, and bilateral symmetry. Directional Terms: indicate the relationship of one part of the body to another. 1. 2. 3. 4. 5. 6. 7. 8. 9. superior (toward the head) inferior (away from the head) anterior (near front of the body) posterior (near back of the body) medial (near midline of the body) lateral (near side of the body) intermediate (between a medial and lateral structure) ipsilateral (same side of the body) contralateral (opposite side of body) 10. 11. 12. 13. 14. 15. proximal (nearer the attachment of an extremity to the trunk or a structure) distal (farther from the attachment of an extremity to the trunk or a structure) superficial (on the surface of the body) deep (away from the surface of the body) parietal (outer wall of a cavity) visceral covering of an organ). Planes Planes are imaginary flat surfaces that are used to divide the body or organs into definite areas. A median plane: is a vertical plane through the midline of the body that divides the body or organs into equal right and left sides A sagittal plane: is a plane parallel to the midsagittal plane that divides the body or organs into unequal right and left sides A frontal/coronal plane: is a plane at a right angle to a median (or sagittal) plane that divides the body or organs into anterior and posterior portions A horizontal/transverse plane: is a plane parallel to the ground and at a right angle to the median, sagittal, and frontal planes that divides the body or organs into superior and inferior portions. Abdominopelvic Regions To describe the location of organs easily, the abdominopelvic cavity may be divided into nine regions by drawing four imaginary lines. The names of the nine abdominopelvic regions are epigastric, right hypochondriac, left hypochondriac, umbilical, right lumbar, left lumbar, hypogastric (pubic), right iliac (inguinal), and left iliac (inguinal). Abdominopelvic Quadrants The abdominopelvic cavity may be divided into four quadrants by passing imaginary horizontal and vertical lines through the umbilicus. The names of the four abdominopelvic quadrants are right upper quadrant (RUQ), left upper quadrant (LUQ), right lower quadrant (RLQ). And left lower quadrant (LLQ). Liver RUQ Section of descending colon LUQ Gallbladder RUQ Lower lobe of right kidney RLQ Duodenum RUQ Cecum RLQ Head of Pancreas RUQ Appendix RLQ Right adrenal gland RUQ Section of ascending colon RLQ Upper lobe of right kidney RUQ Right ovary RLQ Hepatic flexure of colon RUQ Right fallopian tube RLQ Section of ascending colon RUQ Right ureter RLQ Section of transverse colon RUQ Right spermatic cord RLQ Left lobe of liver LUQ Part of uterus RLQ Stomach LUQ Lower lobe of left kidney LLQ Spleen LUQ Sigmoid colon LLQ Upper lobe of left kidney LUQ Section of descending colon LLQ Pancreas LUQ Left ovary LLQ Left adrenal gland LUQ Left fallopian tube LLQ Splenic flexure of colon LUQ Left ureter LLQ Section of transverse colon LUQ Left spermatic cord LLQ Part of uterus LLQ Descriptive Terms of the Body Region Terms used for the body found on your handout. Descriptive Terms of the Body Region Body Cavities Spaces in the body that contain internal organs are called cavities. There are two major body cavities: Dorsal & Ventral Cavity. The dorsal body cavity contains the brain and the spine. It is subdivided into cranial (brain) and vertebral/spinal cavities (spinal cord) Ventral body cavity is the space of the body’s trunk anterior to the vertebral column and posterior to the sternum and abdominal muscle wall. Further divided into: The thoracic cavity (heart, lungs, trachea, etc) and the abdominopelvic cavity (liver, stomach, kidneys, etc). Cranial and Vertebral Cranial Cavity – formed by the cranial bones and contains the brain Vertebral Cavity – formed by the vertebral column and contains spinal cord and the beginnings of spinal nerves Thoracic Cavity Pleural Cavity – each surrounds a lung Pericardial Cavity – surrounds the heart Mediastinum – central portion of thoracic cavity between the lungs, extends from sternum to vertebral column and from neck to diaphram Abdominopelvic Cavity Abdominal cavity – contains stomach, spleen, liver, gallbladder, small intestine, most of large intestine. Pelvic Cavity – contains urinary bladder, portions of large intestine, and internal reproductive organs. BODY CAVITY MEMBRANES The body cavities are lined with serous membranes that provide a smooth surface for the enclosed internal organs. Abdominal cavity membrane: peritoneum. Dorsal cavity membrane: Dura mater Thoracic cavity membrane: pleura Membranes are doubled layered with lubricant fluid between them. The 2 layers: Visceral layer: – the thin membranes that covers an organ in a cavity. Parietal: actual wall of a body cavity or lining membrane that covers its surface. Example: Parietal peritoneum: line abdominal cavity. Visceral peritoneum: lines abdominal organs Levels of Structural Organization The human body consists of several levels of structural organization: chemical, cellular, tissue, organ, system, and organismic levels. The Tissue Level of Organization Chapter 4 Pgs 82-107 Tissue Overview Epithelial Simple Neurons neuroglia Dense Blood Lymph Supporting Cartilage Areolar Adipose Fluid connective tissue Exocrine Endocrine Neural Loose Squamous Cardiac Smooth Skeletal Connective tissue proper (CTP) Muscle Glandular Connective Squamous Cuboidal Columnar Pseudostratified Transitional Stratified Hyaline Elastic Fibrocartilage Bone Membranes Mucous Serous Cutaneous Synovial Epithelial Tissue Includes epithelia and glands Important characteristics: Cells close together Apical surface Free to environment Attachment to basement membrane Avascular Functions of Epithelia Physical protection Controls permeability Provides sensation Produce specialized secretions (glands) Exocrine Endocrine Epithelial Surface The Basement Membrane Keeps epithelial tissue firmly anchored down Epithelial tissue attached to connective tissue Acellular; consists of protein fibers Provides strength and protection Classifying Epithelia 2 name system 1st name based on # cell layers We will study: Simple Stratified 2nd name based on cell shape Columnar Cuboidal squamous Simple Squamous Cuboidal Columnar Pseudostratified columnar Transitional Stratified squamous Epithelial cell shapes: • Squamous cells- the thinnest of the 4, have a flattened nucleus • Cuboidal cells- cubelike with a round nucleus in the center of the cell • Columnar cells- tall with an oval nucleus close to the base of the cell • Transitional cells- change shape (cuboidal when tissue is relaxed, squamous when the tissue is expanded) Glandular Epithelia Endocrine vs. exocrine Exocrine structure Unicellular (Goblet cells) Multicellular Further classified on branching pattern of duct Mode of secretion Merocrine Apocrine Holocrine Connective Tissue Composed of: Cells Extracellular matrix (most of the volume) Ground substance Fibers Never exposed to outside environment Ranges from highly vascularized to avascular Contain many receptors Tanveer Raza MD MS MBBS razajju3@yahoo.com Tanveer Raza MD MS MBBS razajju3@yahoo.com Classification of Connective Tissue Connective Tissue Proper Loose Dense Fluid Connective Tissues Areolar Adipose Blood Lymph Supporting Connective Tissues Cartilage Hyaline Fibrocartilage Elastic Bone (Osseous) Connective Tissue Proper (CTP) Cell Population Connective Tissue Fibers Fibroblasts Macrophages Fat cells (Adipocytes) Mast cells Collagen Elastic Reticular Ground Substance Clear and colorless; similar to syrup Slows movement of pathogens Areolar tissue Areolar tissue: This is the most widely distributed connective tissue in the body of the animals. The main function of this tissue is connective. It usually fixes skin with the muscles and then attaches blood vessels and nerves with the surrounding tissues and fastens the peritoneum to the body wall and the viscera. The other functions of Areolar tissue include formation of the dermis of the skin and submucosa in the wall of the alimentary canal. Fluid Connective Tissues Blood Cells: Matrix: Plasma Extracellular fluid of body composed of: RBCs (half vol of blood) WBCs Platelets Plasma Interstitial fluid Lymph Lymph Respond to injury and infection Supporting Connective Tissue: Cartilage Matrix Cells Firm gel Chondrocytes found in lacunae Avascular Covered by perichondrium 3 major types: Hyaline (vertebral discs) Elastic fibrocartilage The most common type of cartilage in the body is known as hyaline cartilage. It has a very dense matrix with relatively small amounts of collagen and little or no elastin. This makes hyaline cartilage quite strong, though it’s not as strong as bone. Hyaline cartilage is found capping the ends of long bones such as those in the arms and legs. It helps reduce friction and absorb shock, and protect the bones from being chipped and damaged when they move against each other.Hyaline cartilage also makes up the Cshaped bands of tissue that surround the windpipe and prevent it from collapsing. Hyaline Cartilage Elastic cartilage, as you might imagine from the name, contains lots of branching fibers of elastin and other proteins in its matrix. As a result, elastic cartilage isn’t as strong as is hyaline cartilage, but it’s much more flexible and if stretched, will quickly resume its original shape. A good place to find elastic cartilage is in the ear. It makes up the framework of the outer ear, which is why the ear can be so easily deformed, yet returns to its original shape. Elastic cartilage also forms the framework of the epiglottis. Elastic cartilage Fibrocartilage makes up the “disks” of cartilage that separate the vertebrae, for instance. These fibrocartilage pads absorb shock and prevent the vertebrae from being damaged when we jump. Fibrocartilage is also found in the knees, and helps to absorb shock and prevent bone injury when we run and jump. Tanveer Raza MD MS MBBS razajju3@yahoo.com fibrocartilage Mucous Membranes Mucous membranes are epithelial membranes that consist of a mucous-forming epithelium that is attached to an underlying areolar connective tissue. The connective tissue layer is called the lamina propria. These membranes line the body cavities that open to the outside. The entire digestive tract is lined with mucous membranes. Other examples include the respiratory, excretory, and reproductive tracts. Pseudostratified epithelium Lamina propria Serous Membranes Serous membranes line body cavities that do not open directly to the outside, and they cover the organs located in those cavities. Serous membranes are covered by a single layer of squamous cells and a thin layer of serous fluid that is secreted by the epithelium. Serous fluid lubricates the membrane and reduces friction and abrasion when organs in the thoracic or abdominopelvic cavity move against each other or the cavity wall. Serous membranes have special names given according to their location. For example, the serous membrane that lines the thoracic cavity and covers the lungs is called pleura. Connective tissue Simple squamous Thank You For review: Describe the general features of epithelial tissue. Discuss the cells, ground substance, and fibers that compose connective tissue. Define a membrane and describe the location and function of mucous, serous, and synovial membranes.
