Anatomy labs for lab pract. 2 Flashcards
Description and location of Stratum corneum
Most superficial layer, its composed of many layers of keratinized, dead epithelial cells; appear scaly and flattened; resists water loss, abrasion, and absorption.
Description and location of Stratum lucidum
Between stratum corneum and stratum granulosum on soles and palms of thick skin. Cells appear clear; nuclei organelles, and plasma membranes no longer visible.
Description and location of Stratum granulosum
Beneath the stratum corneum (or stratum lucid of thick skin). Three to five layers of flattened granular cells; contain shrunken fibers of keratin and shriveled nuclei.
Description and location of Stratum spinosum
Beneath the stratum granulosum. Many layers of cells w/ centrally located, large, oval nuclei; develop fibers of keratin; cells becoming flattened in superficial portion.
Description and location of Stratum basale
Deepest layer. A single row of cuboidal or columnar cells; layer also includes the melanocytes; frequent cell division; some cells become parts of more superficial layers.
Apocrine sweat gland
Most abundant in the axillary and genital regions. The sweat ducts open into the hair follicles and become active at puberty. Their secretions increase during stress and pain and have little influence on thermoregulation.
Arrector pili muscle
They are attached to the hair follicle and can pull the hair to a more upright position, causing goosebumps when experiencing cold temperatures or fear.
Sebaceous Gland
Secretes an oily sebum into the hair follicles, which keeps the hair and epidermal surface pliable and somewhat waterproof.
Epidermis
The outer layer of skin which consists of stratified squamous epithelium.
Dermis
Inner layer of skin, consists of a superficial papillary region of areolar connective tissue and a thicker and deeper reticular region of dense irregular connective tissue.
Hypodermis
Beneath the Dermis, subcutaneous layer; superficial fascia composed of adipose and areolar connective tissues. The hypodermic is not considered a true layer of the skin.
Hair Papilla
Located at the base of the hair, it contains a network of capillaries that supply the nutrients for cell divisions for hair growth within the hair bulb.
Sweat Glands (sudoriferous glands)
Distributed over most regions of the body and consist of two types of glands.
Eccrine Sweat Glands
Widespread glands that are most numerous on the palms, soles of feet and the forehead. Their ducts open to the surface at a sweat pore. The secretions increase during hot days, physical exercise, and stress; they serve as an excretory function and can help prevent our body temperature from overheating.
Apocrine Sweat Glands
Most abundant in the axillary (arm pit) and genital regions. The sweat ducts open into the hair follicles and become active at puberty. The secretions increase during stress and pain and have little influence on thermoregulation.
Skeletal Muscle
Long, threadlike cells; striated; many nuclei near plasma membrane.
Voluntary movements of skeletal parts; facial expressions or contracting the muscles in your thigh.
Muscles usually attached to bones
Smooth Muscle
Shorter spindle-shaped cells; single central nucleus.
Involuntary movements of internal organs
Walls of hollow internal organs
Cardiac muscle
Branched cells; striated; single nucleus (usually)
Heart contractions to pump blood; involuntary
Heart walls
Nervous Tissue
Neurons w/ long cellular processes; neuroglia smaller and variable
Sensory reception and conduction of action potentials; neuroglia supportive
Brain, spinal cord, and peripheral nerves
Skeletal Muscle Characteristics
Unbranched and relatively parallel cells Striations are present and obvious Nucleus is multinucleate Intercalated discs (junction where cells fit together) is absent Voluntary control
Smooth Muscle Characteristics
Spindle-shaped cells Striations are absent Nucleus is uninucleated Intercalated discs are absent Involuntary control
Cardiac Muscle Characteristics
Branched and connected cells in complex networks Striations are present but faint Nucleus is usually uninucleated Intercalated discs are present Involuntary control
Name the three types of muscle tissues
Skeletal, smooth, and cardiac
Which muscle tissue is under conscious control?
Skeletal