Interstitial fluid is ECF between cells and tissues
Plasma is ECF of blood
Other examples of ECF:
Lymph
Synovial fluid
Intra- = inside, Extra- = Outside, Inter- = between
Scales of Measurement
System of measurement in anatomy is the metric system
Meter
Micrometer
Liter
Milliliter
Kilogram
Anatomical Terminology
A standard position/frame of reference = Anatomical Position
Specific, unambiguous terminology to describe anatomical relationships.
Directional terms
Regional names
Body cavities
Gross Anatomy - Introduction
Regional and directional terms
Anatomical position:
Person stands erect with feet together and eyes forward
Palms face anteriorly with the thumbs pointed away from the body
Regional Terms
Axial region
Axis of body – head, neck, and trunk
Appendicular region
Appendages
Standard Directional Terms
Used by professionals to describe the location of one body part in relation to another
Precise Location
Directional terms are used to explain the precise location of a body structure in relation to another body structure
Terms are paired with opposites
Superior (Cranial) / Inferior (Caudal)
Anterior (Ventral) / Posterior (Dorsal)
Medial / Lateral
Proximal / Distal
Superficial / Deep
Ipsilateral / Contralateral
Directional Terms
Superior: Above, top, toward the head
Inferior: Below, bottom, away from the head
*Describe the position of one body part in relation to another
Medial: Toward the midline
Lateral: Away from the midline
*Used on the torso (axis)
Proximal: Nearest to the origination
Distal: Farther from origination
*Used on the limbs (appendages)
Anterior (Ventral): Toward the front (belly side)
Posterior (Dorsal): Toward the back (back side)
Ipsilateral: Same side of the body
Contralateral: Opposite side of the body
*Right arm is ipsilateral to the right leg
*Right arm is contralateral to the left leg
Superficial: Towards the surface
*Deep: Towards the core of the body
Orientation and Directional Terms
Superior (Cranial): Toward the head end or upper part of a structure or the body; above. Example: The head is superior to the abdomen.
Inferior (Caudal): Away from the head end or toward the lower part of a structure or the body; below. Example: The intestines are inferior to the liver.
Medial: Toward or at the midline of the body; on the inner side of. Example: The heart is medial to the lungs.
Lateral: Away from the midline of the body; on the outer side of. Example: The thumb is lateral to the pinky.
Proximal: Closer to the origin of the body part or the point of attachment of a limb to the body trunk. Example: 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. Example: The knee is distal to the thigh.
Ipsilateral: On the same side. Example: The right hand and right foot are ipsilateral.
Contralateral: On opposite sides. Example: The right hand and left foot are contralateral.
Anterior (Ventral): Toward or at the front of the body; in front of. Example: The sternum is anterior to the heart.
Posterior (Dorsal): Toward or at the back of the body; behind. Example: The vertebra is posterior to the heart.
Superficial (External): Toward or at the body surface. Example: The skin is superficial to the skeletal muscles.
Deep (Internal): Away from the body surface; more internal. Example: The lungs are deep to the skin.
Anatomical Descriptive and Directional Terms
Superior (cranial): Toward the head
Inferior (caudal): Toward the bottom (tail)
Anterior (ventral): Toward the front
Posterior (dorsal): Toward the back
Medial: Toward the midline of the body
Lateral: Toward the side of the body
Internal (deep): Away from the surface of the body
External (superficial): Toward the surface of the body
Proximal: Toward the main mass of the body
Distal: Away from the main mass of the body
Visceral: Related to internal organs
Parietal: Related to the body walls
Body Planes and Sections
Frontal (coronal) plane:
Lies vertically and divides body into anterior and posterior parts
Transverse plane:
Runs horizontally and divides body into superior and inferior parts
Sagittal planes:
Are vertical
Divide the body into right and left parts
Median (midsagittal) plane
Sagittal plane that runs along the midline
Parasagittal planes
A sagittal plane offset from the midline
The Human Body Plan
Tube-within-a-tube
Bilateral symmetry
Dorsal hollow nerve cord
Notochord and vertebrae
Segmentation
Pharyngeal pouches
Body Cavities and Membranes
Body Cavities:
Any space or compartment in the human body.
Cavities accommodate organs and other structures; cavities as potential spaces contain fluid.
The two largest human body cavities are the ventral body cavity, and the dorsal body cavity.
Other human body cavities: oral, nasal, orbital, middle ear, and synovial
Dorsal body cavity:
Divided into two parts:
Cranial cavity:
Superior cavity
Contains the brain
Vertebral cavity:
Inferior cavity
Contains the spinal cord
Both cavities surrounded by the meninges and cerebrospinal fluid
Ventral body cavity:
Divided into two parts:
Thoracic cavity
Superior portion
Abdominopelvic cavity
Inferior portion
Separated by the Diaphragm
Thoracic cavity:
Divided into three parts
Pleural Cavity
Two lateral cavities, each containing a lung surrounded by pleural membranes
Mediastinum
Single middle cavity
Contains the heart surrounded by the pericardial membranes (Pericardial Cavity)
Abdominopelvic cavity:
Divided into two parts:
Abdominal cavity
Contains the liver, stomach, kidneys, and other organs
Pelvic cavity
Contains the bladder, some reproductive organs, and rectum
Body Membranes
Epithelial and/or connective tissue that surround and structure
Protect, lubricate, secrete, and/or absorb
Two types of body membranes:
Epithelial:
Cutaneous
Mucous
Serous
Connective:
Synovial
Types of Membranes
Cutaneous:
Top Layer: Epithelial
Bottom Layer: Connective
Location: Skin
Function: Protection
Mucous:
Top Layer: Epithelial
Bottom Layer: Connective
Location: Organs that encounter the outer environment such as Nasal Cavities, Oral Cavity, Mouth, Anus, Vagina
Function: Protect, lubricate, secrete, absorb. Fluid is Mucous
Serous:
Top Layer: Epithelial
Bottom Layer: Connective
Location: Organs that do not encounter the outer environment such as Heart, Lungs, Intestine
Function: Lubricate. Fluid is Serous
Synovial:
Tissue Type: Connective
Location: Organs that do not encounter the outer environment, specifically Free moveable joints, e.g., shoulder, elbow, hip, knee
Function: Lubricate to reduce friction. Fluid is Synovial
Serous Cavities
A slit-like space lined by a serous membrane
Pleura, pericardium, and peritoneum
Parietal serosa
Covers the outer wall of the cavity
Visceral serosa
Covers the visceral organs
Cavity
Space between Parietal and Visceral Serosa
Contains fluid, produced by both Serosa
Function: lubrication, decrease friction, movement
Pleural Serosa:
Parietal Pleura
Pleural Cavity (with Pleural Fluid
Visceral Pleura
Pericardial Serosa:
Parietal Pericardium
Pericardial Cavity (with Pericardial Fluid)
Visceral Pericardium
Peritoneal Serosa:
Parietal Peritoneal
Peritoneal Cavity (with Peritoneal Fluid)
Visceral Peritoneal
Abdominal Quadrants
Abdominal quadrants divide the abdomen into four quadrants:
Right Upper Quadrant (RUQ)
Left Upper Quadrant (LUQ)
Right Lower Quadrant (RLQ)
Left Lower Quadrant (LLQ)
Abdominal Regions
Abdominal Regions divide the abdomen into nine regions:
Not every structure in every individual is identical.
Structures can vary due to:
Age, sex, height, weight of an individual
Health status (healthy or sick)
Variations include:
Blood vessels branching at different locations
Structures, blood vessels, and nerves being out of place
Small muscles missing
90% of human body structures match textbook descriptions.
Extreme variations are incompatible with life.
Microscopic Anatomy
Microscopy—examining small structures through a microscope
Light microscopy illuminates tissue with a beam of light (lower magnification)
Electron microscopy uses beams of electrons (higher magnification)
Preparing human tissue for microscopy
Specimen is fixed (preserved) and sectioned
Specimen is stained to distinguish anatomical structures
Acidic stain—negatively charged dye molecules
Basic stain—positively charged dye molecules
Scanning electron microscopy
Heavy metal salt stain—deflects electrons in the beam to different extents
Artifacts
Minor distortions of preserved tissues
Not exactly like living tissues and organs
Clinical Anatomy – Medical Imaging Techniques
X-ray—electromagnetic waves of very short length
Best for visualizing bones and abnormal dense structures
Computed (axial) tomography (CT or CAT)
Takes successive X-rays around a person’s full circumference
Computer translates recorded information into a detailed picture of the body section
Angiography
Contrast medium highlights vessel structure
Digital subtraction angiography (DSA)
Images taken before and after contrast medium injection
Computer subtracts “before” from “after” to identify blockage of arteries to the heart wall and brain
Positron emission tomography (PET)—forms images by detecting radioactive isotopes injected into the body
Sonography (ultrasound imaging)—body is probed with pulses of high-frequency sound waves that echo off the body’s tissues
Imaging technique used to determine the age of a developing fetus
Magnetic resonance imaging (MRI)—produces high-quality images of soft tissues
Distinguishes body tissues based on relative water content
Different Imaging Tests
X-Ray
Imaging Method: Ionizing radiation
Used to Diagnose: Bone fractures, arthritis, osteoporosis, infections, breast cancer, swallowed items, digestive tract problems
What to Expect: You will lie, sit, or stand while the x-ray machine takes images. You may be asked to move into several positions.
Duration: 10-15 minutes
CT Scan
Imaging Method: Ionizing radiation
Used to Diagnose: Injuries from trauma, bone fractures, tumors and cancers, vascular disease, heart disease, infections, used to guide biopsies
What to Expect: You will lie on a table that slides into the scanner, which looks like a large doughnut. The x-ray tube rotates around you to take images.
Duration: 10-15 minutes
MRI
Imaging Method: Magnetic waves
Used to Diagnose: Aneurysms, Multiple Sclerosis (MS), stroke, spinal cord disorders, tumors, blood vessel issues, joint or tendon injuries
What to Expect: You lie on a table that slides into the MRI machine, which is deeper and narrower than a CT scanner. The MRI magnets create loud tapping or thumping noises.
Duration: 45 minutes - 1 hour
Ultrasound
Imaging Method: Sound waves
Used to Diagnose: Gallbladder disease, breast lumps, genital/prostate issues, joint inflammation, blood flow problems, monitoring pregnancy, used to guide biopsies
What to Expect: A technician applies gel to your skin, then presses a small probe against it, moving it to capture images of the inside of your body.
Duration: 30 minutes - 1 hour
PET Scan
Imaging Method: Radiotracers
Used to Diagnose: Cancer, heart disease, coronary artery disease, Alzheimer's Disease, seizures, epilepsy, Parkinson's Disease
What to Expect: You swallow or have a radiotracer injected. You then enter a PET scanner (which looks like a CT scanner) which reads the radiation gives off by the radiotracer.