BIOL2141 Exam 2 Study Guide

Epithelial, Connective, Muscle, Nervous

Name the 4 classes of tissue

polarity, specialized contacts, supported by underlying connective tissue, avascular but innervated, regenerative 

Name the 5 characteristics of epithelial tissue

protection, absorption, filtration, excretion, secretion, sensory reception

Name the 6 functions of epithelial tissue

covering and lining and glandular epithelia

Name the two main types of epithelial tissue

sodium potassium pump 

The apical surface of epithelial tissue tends to be negatively charged due to the ___________________

basal lamina

adhesive sheet made up of glycoproteins and collagen fibers adjacent to basal surface of epithelia

tight junctions and desmosomes

covering and lining epithelial tissues fit closely together due to ____________ and ____________

Reticular lamina 

network of collagen fibers deep to basal lamina

Basement membrane

Basal lamina + reticular lamina together; reinforces epithelial sheet, defines epithelial boundary, and resists stretching and tearing

Diffusion

Epithelial tissue must be nourished by _________ from underlying connective tissues

simple epithelia

single layer of epithelial cells

stratified epithelia

two or more layers of cells

Squamous cells

flattened and scalelike, nucleus flattened

cuboidal

boxlike, round nucleus

columnar

tall; column shaped with an elongated nucleus

apical layer 

In stratified epithelia, epithelia is classified by cell shape in the ____________

Holocrine

___________ glands accumulate secretions until rupturing, releasing secretions and dead cell fragments; only found in sebaceous oil glands 

Merocrine

__________ glands secrete product by exocytosis as it is produced; most common secretion type; found in sweat, salivary, and pancreas

connective tissue proper, cartilage, bone, blood

Name the 4 classes of connective tissue

Binding and support, protecting, insulating, storing reserve fuel, transporting substances

Name the 5 major functions of connective tissue 

Mesenchyme

Connective tissues have ______________ as their common tissue of origin 

ground substance, fibers, cells

Name the 3 structural elements of connective tissue

interstitial fluid, cell adhesion proteins, proteoglycans

Name the components of CT ground substance

collagen fiber

strongest and most abundant fiber type; tough, provides high tensile strength

elastic fibers

networks of long, thin, elastin fibers that allow for stretch and recoil

reticular fibers

short, fine, highly branched collagenous fibers that branch, forming networks that offer more “give”

blast cells

immature cell form; mitotically active; secrete ground substance and fibers

fibroblasts

also called reticular cells; most common cells in connective tissue proper

chondroblasts

most abundant blast cells in cartilage

osteoblasts

most abundant blast cells in bone

hematopoietic stem cells

most abundant blast cells in blood; found in red bone marrow

Cyte cells

mature cell form; maintain the health of the matrix

Chondrocytes

most abundant cyte cells in cartilage

osteocytes

most abundant cyte cells in bone

Fat cells- Adipocytes

these cells store nutrients 

Mast cells

cells that initiate local inflammatory response against foreign microorganisms they detect 

Macrophages

phagocytic cells that “eat” dead calls and microorganisms; function in immune system

epithelium and underylying connective tissue proper 

Covering and lining membranes are made of what two primary tissue types? 

cutaneous, mucous, serous

Name the 3 covering and lining membrane types

inflammation, organization, regeneration and fibrosis

Name the 3 steps of tissue repair

Regeneration

tissue repair type in which the same kind of tissue replaces destroyed tissue and original function is restored

Fibrosis

tissue repair type in which connective tissue replaces destroyed tissue and original function is lost 

epithelial, bone, areolar connective tissue, dense irregular connective tissue, blood forming tissue

What tissue types regenerate extremely well?

smooth muscle and dense regular connective tissue

what tissue types regenerate moderately well?

skeletal muscle and cartilage

what tissue types have poor regenerative capacity?

cardiac muscle and nervous tissue of brain and spinal cord

what tissue types have virtually no functional regenerative capacity?

ectoderm

Nerve tissue arises from ____________

Mesoderm

muscle and connective tissues arise from ____________

Endoderm, mesoderm, ectoderm

epithelial tissues arise from ____________ , ____________, and ____________

stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, stratum corneum 

Name the 5 distinct layers of the epidermis from deepest to most superficial 

keratinocytes, melanocytes, dendritic cells, tactile cells

Name the 4 cell types found in the epidermis

stratum basale

deepest epidermal layer; one row of actively mitotic stem cells; some newly formed cells move to other layers; melanocytes compose 10-25% of this layer; also called stratum germanitivum

stratum spinosum

above the stratum basale; several layers thick; cells contain web like system of intermediate prekeratin filaments attached to desmosomes; abundant melanosomes and dendritic cells

stratum granulosum 

above stratum spinosum; thin-4 to 6 cell layers; cells flatten, nuclei and organelles disintegrate, keratinization begins in this layer; cells accumulate keratohyaline and lamellar granules

stratum lucidum

found only in thick soles of feet and palms; thin, translucent band superficial to stratum granulosum consisting of a few rows of flat, dead keratinocytes

stratum corneum

also called the horny layer; most superficial layer of epidermis; 20-30 rows of dead, flat, anucleate keratinized membranous sacs; makes up ¾ of epidermal thickness 

papillary dermis

areolar connective tissue with collagen, elastic fibers, and blood vessels directly beneath epidermis

friction ridges

thick skin lying atop dermal ridges; enhance gripping ability, contribute to sense. of touch, make up fingerprints

reticular dermis

dense fibrous connective tissue with elastic and collagen fibers to provide flexibility and strength to the dermis

Cleavage Lines

externally invisible lines in the reticular dermis running parallel to skin surface; important to surgeons because incisions parallel to these gap less and heal more readily 

Flexure lines

dermal folds at or near joints; dermis tightly secured to deeper structures, so skin cannot slide easily for joint movement causing deep creases; found on hands, wrists, fingers, soles, toes 

Striae

“stretch marks” silvery-white dermal tears caused by stretching

blister

fluid filled pocket that separates epidermal and dermal layers

melanin, carotene, hemoglobin 

name the 3 pigments that contribute to skin color 

Melanin

pigment made in the skin; two forms from reddish-yellow to brownish-black; produced in melanocytes and protects nuclei from UV radiation 

carotene

yellow to orange pigment found in certain plants like carrots that accumulates in stratum corneum and hypodermis 

hemoglobin

when oxygenated, this causes a pinkish hue on fair skin

cyanosis

blue skin color, usually due to low oxygenation of hemoglobin

erythema

redness caused by fever, hypertension, inflammation, or allergy

pallor

blanching caused by anemia, low blood pressure, fear, or anger

jaundice 

yellow cast caused by liver injury or disorder 

bronzing

fake tan color caused by inadequate steroid hormones in Addison’s disease 

bruise

clotted blood beneath skin

hair, nails, cutaneous glands

Name the appendages of the skin

hair shaft, hair root, hair bulb

name the 3 parts of a hair

arrector pili

accessory smooth muscle attached to hair follicles responsible for producing “goosebumps” 

vellus hair

pale, fine body hair of children and adult females

terminal hair

coarse, long hair of eyebrows and scalp, and in axillary and pubic regions of both sexes at puberty 

alopecia

hair thinning in both sexes after age 40

nails

scalelike modifications of epidermis forming a protective cover for distal dorsal surfaces of fingers and toes; made of hard keratin 

Eccrine sweat glands

most numerous sudoriferous glands, abundant on palms, soles of feet, and forehead; merocrine type secretions with ducts connecting to pores on surface of the skin; secrete sweat and function in thermoregulation 

apocrine sweat glands

sweat glands confined to axillary and anogenital areas; secrete sweat, fatty substances, and proteins; ducts empty into hair follicles

sebaceous glands

widely distributed holocrine glands that secrete sebum; most develop from hair follicles and secrete into hair follicles 

protection, body temperature regulation, cutaneous sensations, metabolic functions, blood reservoir, excretion

Name the 6 functions of the integumentary system

chemical, physical, biological

Name the 3 types of protective barriers of the integumentary system

Chemical

skin secretions and melanin are important ___________ barriers

physical 

the flat cells of the stratum corneum surrounded by lipids act as an important _____________ barrier to limit penetration of most water and water soluble substances 

biological

dendritic cells of the epidermis, macrophages of the dermis, and electrons surrounding DNA all act as important _____________ barriers in the integumentary system

Meissners corpuscles

located in the dermal papillae and are responsible for sensing light touch

Panician corpuscles

located in the deep dermis and are responsible for sensing deep pressure

free nerve endings

located in the dermal part of the nervous system and are responsible for detecting temperature, touch, and pain

blood volume

the epidermis makes up to 5% of the body’s _____________

athlete’s foot

epidermal infection of the foot caused by fungus

Pustules, boils, carbuncles

epidermal infections caused by bacteria

cold sores

epidermal condition usually found around the mouth caused by a virus

impetigo

very contagious bacterial (staphylococcus) infection common around the nose and mouth

psoriasis

most likely autoimmune skin disease causing overproduction of skin cells; can be triggered by trauma, infection, or stress. not contagious 

Basal cell carcinoma 

Least malignant and most common skin cancer in which stratum basale cells proliferate and slowly invade the dermis and hypodermis. Cured by surgical excision in 99% of cases 

Squamous cell carcinoma

second most common type of skin cancer involving keratinocytes of stratum spinosum; usually identified by scaly reddened papule on scalp, ears, lower lip, and hands; good prognosis if treated with radiation or surgically removed but can metastasize 

Melanoma

Most dangerous and highly metastatic type of skin cancer involving the melanocytes; resistant to chemotherapy and treated by wide surgical excision accompanied by immunotherapy; key to survival is early detection with ABCD rule