Medical Assistant Course

Plasma membrane

selectively permeable, made of phospholipids and proteins surrounding the entire cell. seperates the internal components of the cell from the surrounding environment. ESSENTIAL FOR LIFE OF CELL

cytoplasm

Gel-like fluid filling the inside of the cell that is comprised primarily of water, with electrolytes, metabolic waste products, and nutrients dissolved vvithin it. Contains many suspended organelles, or cell structures. Medium for chemical reactions

nucleus

Large, spherical body near the center of the cell containing genetic material in the form of DNA. Control center of the cell Regulates cell activity· Houses genetic material

Nuclear membrane

Double-layered, porous membrane surrounding the nucleus. Protects the nucleus, allowing in only specific materials

Nucleolus

Dark, dense body within the nucleus without an enclosing membrane; most cells contain one to four. Forms RNA and ribosomes

Mitochondria

Elongated, rod-shaped bodies filled with fluid, containing DNA Known as the "power plant" of the cell. Convert nutrients into energy for use by the cell/body; create adenosine triphosphate (ATP)

Ribosomes

Small granules of RNA found in the nucleolus or cytoplasm. Protein synthesis for both internal and external use

cilia

Short, hair-like microtubules projecting from the cell membrane. Aid in the movement of substances along the surface of the cell

flagella

Long, hair-like microtubules, projecting from the cell membrane. Move the cell itself, through a whiplike motion

endoplasmic reticulum

Complex connection of membranous fluid-filled, flat sacs and tubular channels Connects the cell membrane to the nucleus membrane, as well as some organelles Comprised of the rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER) Transports materials throughout the cell RER: Supports the synthesis and transport of proteins SER: Supports the synthesis of some lipid molecules, including steroids

golgi apparatus

Four to six flat membranous sacs, connected to the endoplasmic reticulum; typically found near the nucleus. "Packaging and shipping plant" of the cell Packages and releases materials secreted by the cell for external use Forms lysosomes for sure within the cell

lysosomes

Sacs surrounded by membranes created by the Golgi apparatus. Digest waste materials iricluding damaged materials found in the cell, old cell components, and materials entering the cell

cytoskeleton

Comprised of protein microfilaments and microtubules. Maintains the shape and structure of the cell Keeps organelles in place and moves them throughout the cell as needed

centrioles

Maintains the shape and structure of the cell Keeps organelles in place and moves them throughout the cell as needed. Participate in cell reproduction through the distribution of DNA to new cells

sagittal plane

Divides the body into left and right sides. Midsagittal refers to an equal division of left and right sides, running along the midline of the body

transverse plane

Divides the body into upper and lower sections, not necessarily equally

frontal plane

Also called coronal plane, divides the body into anterior and posterior sections

cranial cavity

Within the skull; houses the meninges (brain)

spinal cavity

Traveling down the midline of the back and formed by the vertebrae, this contains the spinal cord

thoracic cavity

Within the chest; houses the lungs, heart, and major vessels

abdominal cavity

Within the abdomen; houses several major organs such as the stomach, liver, gallbladder, and intestines

pelvic cavity

Inferior to the abdominal cavity; houses the bladder and reproductive organs

inregumentary system

hair, skin, nails

skin

Responsible for protection, temperature regulation, sensation, excretion, and vitamin D production 0 Epidermis layer: Outermost layer of epithelial tissue, covers the external surface of the body Dermis layer: Thick layer beneath the dermis that contains arteries, veins, nerves Subcutaneous layer: Loose, connective tissue composed of adipose tissue and lipocytes

hair follicles

generate hair

sebaceous glands

Produce sebum to keep skin and hair soft and prevent bacteria from growing on the skin

sudoriferous glands

produce sweat to aid in cooling the body

skeletal system

axial + appedicular skeleton, ligaments, tendons, connective tissue/cartilage

long bones

These bones have epiphysis, diaphysis, and medullary cavity containing yellow bone marrow. The ends of long bones are covered by articular cartilage to allow joint movement without causing friction. Examples: femur, humerus, tibia, fibula, ulna, radius

short bones

These are found in the wrists and ankles. Short bones are typically small and round. Examples: carpals, tarsals

flat bones

The majority of surface area of these bones are flat or slightly curved. Examples: skull, ribs

irregular bones

These include bones with an unusual shape that is typically related to its function. Examples: vertebrae, pelvis

sesamoid bones

These small, round bones are found in joints that are held in place by tendons. Example: patella

red bone marrow

found within bones, responsible for producing new blood cells in a process known as hermatopoiesis. also store calcium essential for proper cell function

skeletal muscle

Responsible for body movement; also called voluntary muscle or striated muscle

smooth muscle

Found within the walls of hollow organs and blood vessels and in the iris of the eye; also called involuntary muscle

cardiac muscle

Found only in the heart; cross-fibered to allow the heart to contract from the top and bottom to pump blood