A&P Exam 2
Terms in this set (90)
Four types of tissues
Epithelial, Connective, Nerve & Muscle.
avascular (without blood vessels) but nervous innervation. Regenerative tissue capable of undergoing mitosis.
one or more epithelial cells that makes and secretes an aqueous fluid.
"Ductless" glands that produce hormones. Secrete their products into neighboring blood vessels where it is picked up and dispersed throughout the body.
"Ducted" glands which are more numerous than the endocrine type. Secrete their products through the ducts onto body surfaces (skin) or into body cavities. Examples - mucous, sweat, oil and salivary glands
Most important "unicellular" (single cell) gland associated with columnar epithelial cells. Found in areas such as the trachea where they produce and secrete mucus to coat the inner wall of the windpipe.
2) Connective Tissue
Connective Tissue Proper, Cartilage, Bone, Blood
Connective tissue arises from
All arise from "Mesenchyme" as tissue of origin. (Messenchymal stem cells)
Collagen, Elastic, Reticular
Fibroblasts (connective tissue proper), Chondroblasts (cartilage), Osteoblasts (bone), Hemotopoietic stem cells (blood)
Branched neurons with long cellular processes. Transmits electrical signals from receptors to effectors. Found in brain, spinal cord and peripheral nerves.
Voluntary muscle. Long cylindrical, multi-nucleate cells.Striations resulting from contractile elements within the cells.
Involuntary muscle. Branching, uni-nucleated cells with the visible striations as seen in skeletal muscle (and for the same reason). (cardiac muscle cont.) Propels blood into the circulation. Found in the walls of the heart. Cardiac muscle is stimulated by the hearts internal nerve conduction system.
Involuntary muscle without striations. Spindle shaped cells with single central nucleus. Propels substances (food stuffs) along internal passageways by "peristalsis", which is the rhythmic contraction of the smooth muscle? Found in the walls of hollow organs (primarily the intestines) and walls of blood vessels. Smooth muscle is stimulated to contract primarily by stimulus at "stretch" receptors.
damage to any tissue, external or internally, may cause "inflammation"which is characterized by dilation of blood vessels & increased vessel permeability.
The cardinal "signs & symptoms" of inflammation are
Pain, Redness, Swelling, Heat
These signs & symptoms of inflammation are the result of
dilated blood vessels & the increase in permeability allowing fluid to escape into the tissue space. This interstitial fluid is now termed "edema" therefore swelling is occurring. The swollen area is stimulating the pain receptors. Beneficial "pyrogenic" chemicals from the blood (as well as dilated blood vessels) are resulting in heat and redness.
Inflammation is initially a beneficial process
to healing as the increased permeability is delivering needed nutrients into damaged tissue which is trying to repair itself. The heat and swelling can also confine the bacterial pathogens to a limited region of the body a reduce the bacteria's ability to replicate itself. However, as the inflammatory response persists the symptoms listed above can then begin to destroy the healthy tissue and become problematic itself.
Is the replacement of lost or damaged cells & tissue with "normal" appearing cells/tissue both in their anatomy & physiology.
Is the replacement of lost or damaged cells & tissue with connective tissue and results in what we think of as "scar" tissue.
Steps in Tissue Repair
1. Restored blood supply to the site of injury. 2. Regeneration and Fibrosis - surface epithelial tissue regenerates and new connective tissue is formed (fibrosis). 3. Fibrous connective tissue matures. 4.Result is a fully regenerated epithelium with underlying scar tissue
Keratinized stratified squamous epithelium.
Cell types in epidermis
Keratinocytes, Melanocytes, Langerhan's cells, Merkel cells
produce fribrous protein
touch receptors associated with nerve endings
macrophages that activate the immune system
Middle layer composed of strong, flexible connective tissue.
Cell types in dermis
Fibroblasts, Macrophages, White blood cells, Meissner's corpuscles (nerve endings) and Free nerve endings.
Deepest layer composed of adipose and areolar connective tissue
Produced by melanocytes. Yellow to reddish-brown to black pigment responsible for dark skin colors. "Natural Sun Screen"
Yellow to orange pigment. Palms and soles of feet.
Reddish pigment due to oxygen binding to hemoglobin in red blood cells.
Blueish coloration due to decreased binding of oxygen.
In the ear canal. Secrete "cerumen"
Found all over the body except palms & soles. Secrete "sebum", an oily secretion into hair follicles and onto skin surface. "Acne" --- bacterial infection of the sebaceous glands.
Functions of The Integumentary System
1. Protection is provided as chemical, physical and mechanical barriers by the skin and the associated structures (hair, nails, glands and their secretions). 2. Body temperature regulation - How does it regulate body temperature? 3. Cutaneous sensation - Pain and touch receptors. Adaptation - Most receptors with the exception of the "pain" receptors undergo adaptation. This means a decrease in perception in the presence of a constant stimulus. You are no longer consciously aware of something even though it is still in contact with the receptors. 4. Vitamin D synthesis. 5. Blood reservoir - Up to 5% of the body's blood volume is in the skin 6. Excretion - Waste products along with heat, are released in the sweat
Non-homeostatic condition resulting in white patches in/on the skin due to loss of pigmentation (melanin) from the melanocytes. Autoimmune disorder(
) with some genetic history in the family.
Autoimmune is where an individual's immune system has begun to abnormally interfere with the function of once healthy cells.
Basal Cell Carcinoma
Least malignant and most common skin cancer. Slow growing. Can generally be cured by surgical excision.
Squamous Cell Carcinoma
Involves the "keratinocytes". Found in scalp, ears, and lower lip. Grows rapidly and metastasizes. Prognosis generally good if caught early.
Involves the "melanocytes". Most dangerous. Highly metastatic. The majority of melanoma and non-melanoma cancers are related to a loss or diminished activity of the "p53 gene" therefore loss or diminished p53 tumor suppressor protein.
Asymmetry - Do the 2 sides of the pigmented area match?
Border - Is the border regular/irregular and exhibit indentations?
Color - Is the pigmentation changing?
Diameter - Diameter larger than 4-6 mm (pencil eraser size) is of concern
No blood vessels (avascular) Surrounded by "perichondrium", connective tissue which encapsulates the cartilage.
Most abundant. Present on articular surfaces (around bone ends), costal regions (ribs), respiratory regions (trachea) and nasal passages.
Functions of Bones
Support, protection, movement, mineral storage (calcium), blood cell formation (Hematopoiesis)
Dense outer layer
Honeycomb of trabeculae forming inner bone.
Tubular shaft. Compact bone surrounding a "medulary cavity" filled with yellow bone marrow.
Expanded ends of long bones. Compact bone with spongy bone interior. Surface covered with hyaline cartilage. Epiphyseal Line separates the diaphysis from epiphysis.
Protective outer membrane with osteoblasts and osteoclasts, nerve fibers, blood vessels, and lymphatic vessels.
In the medullary cavity and all spongy bone
In the flat bones (such as skull bones) & the ends of the femur & humerus.
Mature bone cells
Resorb or break down bone
The process of bone tissue formation which begins at approximately the 8th week of embryonic development.
is bone formation from connective tissue and is the type that occurs in the skull bones and clavicles.
is conversion of cartilage to bone. Most bones of the skeleton form through this type of ossification. Begins in the second month of development and uses hyaline cartilage as the template for bone formation.
Postnatal Long Bone Growth
Growth of long bones through ossification of cartilage in the "epiphyseal plates" (growth plates.) During infancy and childhood plate ossification is stimulated by "growth hormone" and later, at the onset of puberty, by "testosterone and estrogens".
At the conclusion of long bone growth a remnant of cartilage cells exists where the plate was located. This line is now the weak spot of long bones and a common site for fracture
Osteoblast and osteoclasts deposit and resorb (respectively) bone at the same pace.
Occurs where bone is injured or added strength is needed.
Osteoclasts create grooves or furrows then digest bone matrix by lysosomal enzymes. Solubilized "calcium" can be released from the bone and in to the blood vascular system for use elsewhere in the body.
necessary for bone formation.
Hormone secreted by the thyroid gland in response to elevated blood calcium. Stimulates calcium movement from the vascular system and in to the skeletal system.
Parathyroid Hormone (PTH)
Hormone secreted by the parathyroid glands in response to decreased calcium in the blood. PTH stimulates osteoclasts to degrade bone and move calcium out of the skeletal system and in to the blood.
Ends of broken bones are in alignment
Malalignment of broken bone ends. Out of alignment so more prone to soft tissue injury.
Bone is fractured completely through from side to side
Such as in a hairline fracture or not broken all the way through the bone
Fracture is longitudinal to the length of a long bone
Resembles a cross section fracture to the bone
Bone fragment(s) penetrate through the skin and outside the body. Must now be more cautious of infectious agents penetrating into the body.
All bone fragments are contained within the body
Multiple pieces, or 2 or more bone fragments
Such as twisting around the axis of a long bone. Common in sports injuries.
Generally found in skull bones from blunt force trauma forcing the bone inward.
Example would be the pressing of one body of a vertebrae between that one above and below the fracture.
Fracture of the epiphysis from the diaphysis of a long bone at the site of the epiphyseal plate (during growing years) or the epiphyseal line in the post growing years.
Commonly seen in young children. The area of unossified cartilage will bend while that where cartilage has already ossified to bone will break.
Stages in Healing a Fracture
1. Hematoma formation - Swelling, pain, heat, redness (inflammation) and blood clotting at the site of torn blood vessels. 2. Blood supply re-established. Fibrocartilaginous, "soft" callus forms to provide an internal splint between the fractured bone ends. 3. New bone trabeculae appear (spongy bone area) and the fibrocartilage ossifies into a bone, "hard" callus beginning approximately 3-4 weeks after injury. 4. Bone remodeling - Excess bone material spanning the exterior bone shaft and within the medullary canal area is removed. 5. Compact bone is laid down as a final step.
"Soft Bones". Main symptom = Pain. Caused by insufficient calcium in the diet or by vitamin D deficiency
Soft Bones" in Children. Characterized by bow legs and deformities of the pelvis, skull and rib cage. Caused by insufficient calcium in diet or by vitamin D deficiency. More severe in children than osteomalacia in adults due to children still in their growing years.
Osteoclasts outpace osteoblasts (ie resorption > deposit). Occurs primarily in postmenopausal women. Estrogen is thought to hold the osteoclasts activity in check but as estrogen levels begin to fall off the osteoclasts are left unchecked. HRT (hormone replacement therapy) traditionally the treatment of choice.
Excessive bone formation. Osteoclasts activity diminishes.