Human Bio 2 Exam

Tissue types- Epithelial (what 2 types- number of layers)

Simple- one layer, Stratified- multiple

Epithelial- Types (what shapes of cells)

Squamous (flat) Cuboidal, or columnar (tall than they are wide)

Basement membrane (basal laminate)

protein layer supports epithelium

tight junction

seal between cells

adhesion junction

attach to cytoplasm of adjacent cells for tissue strength

gap junctions

connect cytoplasm of adjacent cells for communication

glandular epithelium- two terms

exocrine- secrete outside into epithelial surface, endocrine- secrete into blood

connective tissue- structure and support

can be lose/dense depends on amount of protein fibers, fewer cells (most common: fibroblast)

protein fibers- two types

collagen- for strength, elastin- for stretch

what are the 4 specialized connective tissues-

cartilage- cushioning cells called chondrocytes, bone- calcium phosphate makes ground substance hard, blood- red/white/platelets, adipose- fat

muscle movement 3 types

skeletal- voluntary, cardiac- heart, smooth- walls of blood vessels and other hollow structures

nervous- communication cell types

neurons- send signals, axon- send signals, dendrites- receive signals, glial cells- supportive cells

the integumentary system- skin and associated structures- layer of skin

epidermis- stratified squamous epithelium

cells: most cells here are keratinocytes

proliferate at basal layer, keratin filaments provide strength and waterproofing, top layers are dead cells

melanocytes

make pigments

dermis

dense, irregular connective tissue, contain structures including blood vessels, nerves sweat glands, hairs, sebaceous glands

hypodermis

loose connective tissue, contains adipose (fat) tissue, cushioning and insulative

skin cancer- 3 main types

cells resemble normal cells of epidermis but are abnormal cancer cells, basal cell carcinoma, melanoma- most malignant (deadly)

what causes skin cancer

uv radiation, damages DNA

chapter 18- cancer

how does it relate to cell cycle

proteins controlling cell cycle are mutated, oncogenes- proteins that normally cause to divide when activated by growth factors, mutation makes them constantly push through cycle

tumor suppressor genes- proteins that normally stop the cell cycle when appropriate

mutations- causes loss of expression or loss of normal function to stop cell cycle

growth factors

stimulate cells to divide

mutations of genes

encoding proteins involved in this leads to cancer

cancer progression

gradual accumulation of mutations in several oncogenes and tumor suppressors