(LESSON 1) Chapter 1-Human Body Flashcards
Hierarchy of the Body
Chemical-Cellular-Tissue-Organ-Organ System-Organism.
Chemical Level
Atoms combine to form small molecules (H20/CO2) and large molecules (Carbs/Sugars, Lipids/Fats, Proteins, and Nucleic Acids (RNA/DNA).
Cellular Level
The cells and their functional subunits, called cellular organelles. Cells are the smallest living things in the body and you have trillions of them.
Tissue Level
A group of cells that work together to perform a common function.
4 Tissue Types
Epithelium/Epithelial Tissue, Connective Tissue, Muscle Tissue, and Nervous Tissue.
Organ Level
Extremely complex physiological processes occur.
Organs
Most organs contain all four tissues. Each organ is a functional center responsible for activity that no other organ can perform.
Organ System Level
Organs that work closely together to accomplish a common purpose.
Organismal Level
The human organism is made up of many organ systems
Integumentary System
(organ system) External body covering, protects deeper tissue from injury, synthesizes Vitamin D, site of cutaneous (pain/pressure) receptors, and sweat and oil glands
Skeletal System
(organ system) Protects and supports body organs, provides framework the muscles use to cause movement, blood cells are formed within bones, stores minerals
Muscular System
(organ system) Allows manipulation of the environment, locomotion, facial expression, maintains posture, produces heat
Nervous System
(organ system) Fast-acting control system of the body, responds to internal and external changes by activating appropriate muscles and glands
Endocrine System
(Organ System) Glands secrete hormones that regulate processes such as growth, reproduction, and nutrient use (metabolism) by body cells
Male/Female reproductive Systems
(organ system) Overall function is production of offspring. Testes produce sperm and male sex hormone, ducts and glands aid in delivery of sperm to female reproductive tract. Ovaries produce eggs and female sex hormones, remaining structures serve as sites for fertilization and development of the fetus. Mammary glands of female breast produce milk to nourish the newborn.
Cardiovascular System
(organ system) Blood vessels transport blood which carries oxygen, CO2, nutrients, wastes, etc; the heart pumps blood.
Lymphatic System/Immunity
(organ system) Picks up fluid leaked from blood vessels and returns it to blood, disposes of debris in the lymphatic stream, houses the white blood cells (lymphocytes) involved in immunity. The immune response mounts the attack against foreign substances within the body.
Respiratory System
(organ system) Keeps blood constantly supplied with oxygen and removes CO2, the gaseous exchanges occur through the walls of the air sacs of the lungs.
Digestive System
(organ system) Breaks down food into absorbable units that enter the blood for distribution to body cells, indigestible foodstuffs are eliminated as feces.
Urinary System
(organ system) Eliminates nitrogenous wastes from the body, regulates water, electrolyte and acid base balance of the blood.
Axial Region
Makes up the main axis of the body: head, neck and trunk.
Thorax
(Chest) The trunk of the body: Chest, abdomen, and pelvis.
Appendicular Region
limbs (Appendages/extremities)
Superior
Cranial. Toward the head end or upper part of a structure. Above.
Inferior
Caudal. Away from the head end or toward the lower part of a structure or the body. below.
Anterior
Ventral. Toward or at the from of the body; in front of.
Posterior
Dorsal. Toward or at the back of the body. Behind.
Medial
Toward or at the midline of the body; on the outer side of.
Proximal
Closer to the origin of the body part or the point of attachment. The elbow is proximal to the wrist.
Distal
Farther from the origin of a body part or the point of attachment of a limb to the body trunk. The Knee is distal to the thigh.
Superficial
External. Toward or at the surface.
Deep
Internal. Away from the body surface.
Ipsilateral
On the same side. The right hand and right foot are ipsilateral.
Contralateral
On opposite sides. The right hand and left foot are contralateral.
Frontal plane
Coronal. Lies vertically and divides the body into anterior and posterior parts.
Transverse plane
Horizontal. Runs horizontally from right to left dividing the body into superior and inferior parts. AKA Cross sections
Sagittal plane
Lies vertically and divides the body into left and right sides
Median plane
Mid Sagittal plane. Sagittal plane that lies exactly at the midline.
Dorsal Body Cavity
Subdivided into Cranial Cavity(skull) and Vertebral Cavity (Vertebral Column)
Ventral Body Cavity
Larger cavity, contains lungs, heart, intestines, kidneys (Visceral organs). 2 main divisions: Superior Thoracic Cavity and Inferior abdominopelvic Cavity
Superior Thoracic Cavity
Surrounded by the ribs and muscles of the chest wall. 3 parts: a. two lateral parts, each containing a lung surrounded by a pleural cavity. b. a central band of organs called the mediastinum.
Inferior Abdominopelvic Cavity
Surrounded by the abdominal walls and pelvic girdle. 2 parts: A. Abdominal Cavity-contains liver, stomach, kidneys, and other organs. B. Pelvic Cavity-contains the bladder, some reproductive organs, and the rectum.
Mediastinum
contains the heart surrounded by a pericardial cavity. Also houses other major thoracic organs such as esophagus(gullet) and trachea(wind pipe).
The Serous Cavities
Pericardial, Pleural, and Peritoneal. Lined by serous membrane, surrounds visceral organs (lungs, heart, intestines, kidneys) like a balloon surrounding a fist. Outer part is parietal serosa, inner part is visceral serosa, and the thin space between is the cavity.
Pericardial Cavity
Associated with the heart. Parietal pericardium is the outer lining, the visceral pericardium clings to the heart.
Pleural Cavities
Around the lungs. Parietal pleura covers the deep surface of the walls of the thoracic cavity; visceral pleura covers each lung.
Peritoneal Cavity
Around some abdominopelvic organs. The parietal peritoneum covers the deep surface of the wall of the abdomen; the visceral peritoneum covers the organs of the peritoneal cavity. Kidneys are retroperitoneal (fully behind peritoneum). Pg 13
Parietal/Visceral Serosa
Outer/inner walls of the cavity.
serous fluid
both serous membranes secrete a thin layer of fluid.
Other cavities
Oral, Nasal, Orbital, Middle Ear, and synovial cavities(surrounding the freely moving joints of the body. Cavity membrane secretes lubricating fluid that reduces friction)
X-Ray Imaging
Very short electromagnetic waves are directed at the body. The more dense the body part, the more it absorbs the rays. The rays that pass through the body expose a piece of film behind the patient to create a “negative”. Dark areas=soft and easily penetrated organs. Lighter areas=bones, tumors, and other dense structures.
Limitations: Can be blurry, 2D images cause organs to appear stacked and many organs are blocked.
Computed Tomography Scan
(Tomography=cross section) Patient lies in central hole of the scanner situated between xray and recorder. The tube rotates to take about 12 xray image angles around the body’s circumference. Image created is a transverse body plane. With a full circumference reading, images show every organ’s best angle with fewest structures blocking. Computer translates info into image where soft structures are represented more clearly.
Positron Emission Tomography
Produces images by detecting radioactive isotopes injected into the body. PET images indicate regions of cellular activity. Assesses functional blood flow to heart and brain.
Drawbacks: Cannot record quick changes in brain activity. Requires cyclotron machine on site to make isotopes.
Sonography or Ultrasound
Body is probed with pulses of high frequency sound waves that reflect(echo) off the body’s tissues. Computer analyzes echoes and constructs sectional images of outlines of organs. Hand held device that looks like a microphone emits the sound and receives echoes. Device is moved across the surface of the body allowing organs to be examined from many different body planes.
Equipment is inexpensive. Safer than ionizing forms of radiation, fewer harmful effects on living tissue. Used to visualize the fetus, gallbladder, arteries.
Magnetic Resonance Imaging
Produces high contrast images of soft tissues. Detects the levels of hydrogen in the body(water). Bones (little water) don’t show up. Can peer right into the brain. Tumors show up distinctly. Patient lies in chamber and subjected to magnetic fields up to 60K times stronger than earth’s. Hydrogen atoms align with magnet, radio waves are pulsed knocking atoms out of alignment, then magnet returns atoms into alignment and atoms emit radio wave signals that are detected by the sensors and computer creates images.
