Chapter 1 Anatomy
Anatomy
Form
Physiology
Function
mediastinum cavity
It contains the heart, thymus, esophagus, trachea, and major blood vessels that connect to the heart.
Specialized branches of anatomy focus on the diagnosis of medical conditions or the advancement of basic scientific research. These branches include the following:
Pathologic and Radiographic anatomy
Gross anatomy includes:
Systemic anatomy, Regional anatomy, Surface anatomy, Comparative anatomy, Embryology
oblique plane
The coronal, transverse and sagittal planes are at perfect 90 degree angles from one another. If a plane is cut at another angle, it is termed
transverse plane
also termed a horizontal plane, divides the body into top (superior) and bottom (inferior) parts.
Ventral body cavities
are lined by serous membranes unlike those of the posterior cavities
The human body is partitioned into two main regions,
axial, and appendicular regions.
abdominal cavity
contains most of the digestive organs along with the kidneys and most of the ureters.
posterior body cavity is subdivided into two enclosed cavities,
cranial, and vertebral cavities
Surface anatomy
focuses on both superficial anatomic markings and the internal body structures that relate to the skin covering them
visceral pericardium
forms the heart's external surface.
Pathophysiology
investigates the relationship between the functioning of an organ system and disease or injury to that organ system.
chemical level
is the simplest level involving atoms and molecules. Atoms are the smallest intact chemical units and molecules are combinations of atoms.
effector
is the structure that brings about the change to alter the stimulus. Its action attempts to bring the variable back into optimal homeostatic range, as dictated by the control unit.
control center
is the structure that interprets input from the receptor and initiates changes through the effector. It serves as the go between, integrating the other two components of the homeostatic system.
Histology
is the study of tissues
Systemic anatomy
studies the anatomy of each functional body system
Cytology
the study of body cells and their internal structure
the serous cavity
Between the parietal layer and visceral layer of serous membranes is a potential space, called
Physiologists examine the function of various organ systems, and typically focus on the molecular or cellular level to gain a complete understanding of the system's workings. These groups include the following:
Cardiovascular physiology, Respiratory physiology, Reproductive physiology, Pathophysiology
receptor, control center, effector
Components of Homeostatic Systems
Anatomic position description
In order to assume the position, the person stands erect and upright with their limbs at their sides, their palms facing anteriorly and feet held together but positioned in a 45-degree angle from one another.
(a) Serous membranes are composed of two layers
a parietal layer and a visceral layer
Serous membranes secrete
a serous fluid that has an oily consistency. Its purpose is to serve as a lubricant that prevents friction when organs rub against one another in the ventral cavities.
1) Microscopic Anatomy
cannot be seen with unaided eye. It includes cytology and histology.
visceral layer
covers the external surface of the lungs
visceral layer
covers the external surface of the organ in the cavity.
Reproductive physiology
explores how the regulation of reproductive hormones can drive the reproductive cycle and influence sex cell production and maturation
pleural cavities
have two layers of serous membranes
axial region
includes the head, neck and trunk
Dorsal
is at the back side of the human body
organism
is the highest level human structural organization, comprised of all of the organ systems working in an integrated functional manner
pleural cavities two, serous membranes called
parietal layer and the other is the visceral layer.
Proximal
refers to a structure on the appendages. It is the structure closest to the point of attachment to the body trunk
Distal
refers to a structure on the appendages. It is the structure farthest away from the point of attachment to the body trunk.
Respiratory physiology
studies how respiratory gases are transferred by gas exchange between the lungs and the blood vessels, supplying the lungs among other things.
The quadrant system divides
the abdominal cavity into a right upper quadrant, right lower quadrant, left upper quadrant, and left lower quadrant.
The main two body cavities are
the posterior cavity and ventral cavity
four quadrants method
using the umbilicus as the central point and having imaginary transverse and midsagittal planes pass through the umbilicus.
Characteristics that Describe Living Things
Organization, Metabolism, Anabolism, Catabolism, Growth, Development (differentiation), Responsiveness, Regulation, Reproduction
Anatomists cannot gain a full appreciation of anatomic form without also understanding a structure's function. Physiologists cannot fully appreciate body functions without learning the form of the structures involved
a
pleural cavities
are located in the right and left sides of the thoracic cavity, they surround the two lungs
Homeostatic control systems
are separated into two broad categories based on whether the system maintains the variable within a normal range by moving the stimulus in the opposite direction, or amplifies the stimulus in the same direction
feedback loop
homeostatic system form a dynamic control system, known as
diagnosis
is a finding of the specific cause of the homeostatic imbalance.
Ventral
is at the belly side of the human body
pericardial cavity
is the potential space between the parietal and visceral pericardium.
peritoneal cavity
is the potential space between the visceral and parietal peritoneum, containing a lubricating fluid: serous fluid.
pelvic cavity
lies inferior to the horizontal plane, at the level of the superior aspects of the hip bones.
abdominal cavity
lies superior to this horizontal plane, at the level of the superior aspects of the hip bones
Disease
occurs when the body is unable to maintain a relatively stable internal environment: homeostatic imbalance
posterior body cavity
contains cavities that are completely encased in bone and are physically and developmentally different from the ventral cavity
Pathologic anatomy
examines all anatomic changes resulting from disease
Regional anatomy
examines all of the structures in a particular region of the body as a complete unit.
Comparative anatomy
examines similarities and the differences in the anatomy of different species.
Cardiovascular physiology
examines the functioning of the heart, blood vessels, and blood.
Anabolism
is a biochemical building process where small molecules are joined to make larger ones.
serous membrane
is a continuous layer of cells, as compared to the plasma membrane, which surrounds a single cell.
Computerized Tomography, CT scan
is a more sophisticated application of X-rays, producing multiple axial images of a body organ or region. The multiple images are processed and analyzed by a computer, thus producing a 3- dimensional image of a thin slice of the body region.
Reproduction
is a process that produces new cells for growth, maintenance and repair. The sex cells are responsible for developing a new living organism
Dynamic Spatial Reconstruction
is a special radiologic technique that provides three-dimensional images of body organs as they move
abdominopelvic cavity
is a subdivision of the ventral body cavity and is separated from the thoracic cavity by a flat dome-shaped muscle, known as the diaphragm.
Example of Negative Feedback
Temperature regulation
Anatomy and physiology initially may appear to be different sciences, but further reflection reveals that these two sciences are integrated, because form (anatomy) and function (physiology) are interrelated
a
The Body's Levels of Organization: Scientists group the body's components into an organized hierarchy of form and function.
a
The feedback loop operates in the following manner:
a stimulus is received by the receptor The receptor information is sent to the control center The control unit integrates the incoming input this dictates a change utilizing the effectors The effectors receive input from the control unit, effecting return of the body to homeostasis.
Homeostatic imbalance may sometimes occur due to a normal process, such as
aging
coronal plane
also termed a frontal plane, is a vertical plane that divides the body into front (anterior) and back (posterior) parts.
The View from Simplest to Most Complex Anatomists and Physiologists recognize several levels of increasing complex organization in humans. In increasing hierarchical order these levels include the following
chemical level, tissue level, organ level, organ system level, organism.
cellular level
consists of cells, which are the smallest living structures and serve as the basic units of structure and function. Interfaced between the chemical level and cellular level are the biochemical macromolecules (carbohydrates, lipids, proteins and nucleic acids) and the cellular substructures these macromolecules form, which are the organelles.
organ system level
contains organs that work together to coordinate activities and achieve a common function.
pelvic cavity
contains the distal part of the large intestine, the remainder of the ureter, the urinary bladder, and the internal reproductive organs.
The ventral cavity subdivisions
contains the thoracic and abdominopelvic cavities
nine compartment method
divides the abdominopelvic cavity into an umbilical region, epigastric region, hypogastric region, right hypochondriac region, left hypochondriac region, right lumbar region, left lumbar region, right iliac region, and left iliac region.
sagittal plane
divides the body into right and left halves. Since the body is intended to be bilaterally symmetrical, a cut down the middle of the head continuing down through the midline of the trunk (through the umbilicus) will divide the body into equal right and left sections, thus termed a midsagittal plane. If the body is divided into unequal right and left parts, it is simply termed a sagittal plane
Radiographic anatomy
investigates the relationships among internal structures that may be visualized by specific scanning procedures, such as the ultrasound, magnetic resonance imaging (MRI), or X-ray
Gross anatomy, also called macroscopic anatomy
investigates the structure and relationships of body parts that are visible to the unaided eye, such as the intestines, stomach, brain, heart, and kidneys.
Catabolism
is a biochemical breaking down process where large molecules are broken down into smaller ones
Anatomic position
is a common agreed upon point of reference used when describing the position of certain anatomical structures in the human body
Digital Subtraction Angiography
is a modified three-dimensional X-ray technique used primarily to observe blood vessels.
peritoneum
is a two-layered serous membrane that lines the abdominopelvic cavity. It also has a parietal layer and visceral layer.
plane
is an imaginary flat surface passing through the body. The planes of the body include the coronal, transverse, sagittal, and oblique planes
Sonography, termed ultrasound,
is an imaging method that transmits high-frequency ultrasonic waves into the body and receives them in order to produce an image of internal organs.
Regulation
is based in homeostasis. The ability to maintain a constant internal environment in the face of a changing external environment
organ level
is composed of human organs that are composed of two or more tissue types that perform specific, complex functions
appendicular region
is composed of the upper and lower limbs, which attach to the axial region.
tissue level
is comprised of groups of similar cells (similar embryonic origin) that collectively form common functions
cranial cavity
is formed by the bones of the cranium, and so it goes by the name endocranium.
vertebral cavity
is formed by the bones of the vertebral column, and houses the spinal cord.
pericardial cavity
is located within the mediastinum
abdominopelvic cavity
is subdivided into two smaller cavities, the abdominal cavity and pelvic cavity, by a horizontal plane at the level of the superior aspects of the hip bones.
Responsiveness
is the ability to sense and react to stimuli
receptor
is the body structure that detects changes in a variable, which is either the substance or process that is regulated. The change in the variable is the stimulus
Organization
is the complex hierarchical structuring of the body.
Embryology
is the discipline concerned with the developmental changes occurring from conception until birth
Growth
is the enlargement in the size of an organism
The visceral peritoneum
is the inner layer of this serous membrane, covering the external surfaces of most of the abdominopelvic organs.
The ventral cavity
is the large, anteriorly placed cavity in the body. Unlike the posterior cavity, the ventral cavity and its subdivisions do not completely encase their organs.
The parietal layer
is the outer layer that surrounds the internal surface of the thoracic wall
parietal pericardium
is the outermost layer of the serous membrane and forms the sac around the heart
parietal peritoneum
is the outermost layer of this serous membrane, lining the internal walls of the abdominopelvic cavity.
Development (differentiation
is the process whereby cells specialize to become more sophisticated for specific functioning, like nerve cells
Metabolism
is the sum of all chemical reactions in the body. Metabolism is subsumed into two interrelated processes, anabolism and catabolism.
Posterior
is toward the back surface.
Anterior
is toward the front surface
pericardial cavity
it encloses the heart in a two-layered serous membrane, called the pericardium.
(a) The parietal layer
lines the internal surface of the body wall.
mediastinum cavity
located in the median space in the thoracic cavity
thoracic cavity a subdivision of the ventral cavity , contains three cavities itself:
mediastinum cavity, pericardial cavity, and the pleural cavity
Negative feedback
moves the variable in the opposite direction
Positive feedback
moves the variable in the same direction
Magnetic Resonance Imaging, MRI
provides non-invasive images of soft body tissues, using a strong magnetic field and radio waves that alters the energy of protons in the nuclei of hydrogen atoms. Since hydrogen atoms are a main component of water molecules, soft tissues possessing higher water contents are viewed better than hard tissues, such as bone, having lower water contents.
set point
the variable is maintained with a normal level called
Positive Emission Tomography (PET scan)
uses radioactively labeled glucose molecules to analyze the metabolic state of a tissue at a given moment in time, thus determining which tissues are most metabolically active.
