Honors Anatomy Unit 2

simple squamous epithelial

simple cuboidal epithelial

simple columnar epithelial

nonkeratinized stratified squamous epithelial

keratinized stratified squamous epithelial

pseudostratified columnar (with cillia)

loose connective (areolar)

adipose

dense regular connective

dense irregular connective

hyaline cartilage

osseus (bone)

hematopoietic tissue (lymphatic)

hematopoietic tissue (blood)

striated (skeletal) muscle

smooth (visceral) muscle

cardiac muscle

nervous tissue

levels of cellular organization

cell

tissue

organ

organ system

organism

histology

study of tissues

4 types of tissues

epithelial, muscle, connective, nervous

epithelial tissue

-upper (apical) surface of epithelium is free space

-lower (basal) surface rests on connective tissue

-basement membrane

-densely packed

-avascular, nutrients diffuse from neighboring connective tissue

-high rate of mitosis

epithelial tissue function

protection, filtration, secretion, absorption, excretion

simple squamous

located in alveoli and lining of blood vessels, nucleus is centrally located

Simple Cuboidal

located in kidney tubules

Ciliated Simple Columnar

located in oviducts/upper respiratory tract

Nonciliated Simple Columnar

located in the Ileum, Gallbladder, and Urinary tract; may contain goblet cells (secrete mucus)

Simple Columnar with microvilli brush border

located in duodenum; microvilli found at apical surface to increase surface area/ absorption

Keratinized Stratified Squamous

located in superficial skin layer; contains filaments of protein keratin → cells accumulate keratin as they age, become tough and water resistant

Non-keratinized Stratified Squamous

located in esophagus, Oral cavity, Vagina, Anal canal; no keratin, must be kept moist

Stratified Cuboidal

found in ducts of mammary, sweat, and salivary glands

Stratified Columnar

located in lining of developing ovarian follicles; very rare

Ciliated Pseudostratified Columnar

found in respiratory passages; cilia = movement of materials; single layer, but nuclei are at different levels and not all cells reach the free surface

Nonciliated Pseudostratified Columnar

located in prostate and vas deferens; no mucus or cilia

Transitional epithelium

located in urinary bladder'; Cells change shape (from squamous to columnar) as body parts stretch and move

Glandular Epithelium

- makes up the secreting portions of exocrine and endocrine glands

- epithelial tissue specialized for secretion

Endocrine Glands

-secretions enter the extracellular fluid and diffuse into the bloodstream

-no ducts

-secretions are called hormones

-Glands include adrenal, thyroid, pituitary

Exocrine Gland

-secrete products into a duct that leads to the surface of the skin or into the lumen (interior space) of a hollow organ

-Glands include sweat, salivary

- hollow

-lined by glandular epithelium.

Merocrine glands

-type of exocrine gland

-Cells secrete their substances by exocytosis

-Salivary and Sudoriferous (sweat) Glands

-think of “emerge” (exocytosis to open spaces)

Apocrine gland

-type of exocrine gland

-portion of the cell membrane that contains the secretion buds off

-Mammary and Ceruminous (earwax) Glands

-think “a-part”/”apical surface” breaks off

Holocrine gland

-type of exocrine gland

-entire cell disintegrates to excrete its substance

-Sebaceous (oil) Glands

-think “whole” cell

Connective tissue

- Most abundant tissue

- Major transport tissue (blood)

- Stored energy (adipose)

- Doesn’t occur on free surfaces

- rich nerve and blood supply (except cartilage)

connective tissue function

- Supports/strengthens/protects/insulates

Mesenchymal Connective Tissue

-first connective tissue to develop in the embryo

-all connective tissues are later derived from
- clusters are scattered throughout adult tissue and supply the cells needed for replacement and repair after connective tissue injury

all connective tissues derive from

mesodermal layer of the embryo

Extracellular Matrix

-material found in space between tissue cells

-contains ground substance and fibers

-produced by the connective tissue cells that are embedded within it

- composed of ground substance + protein fibers

Ground Substance

part of extracellular matrix; can be fluid/semi-fluid/gelatinous/calcified

Protein Fibers

part of extracellular matrix; composed of one or more types: collagen, elastic, reticular

“-blast” cells

immature; secrete the matrix and produce new cells; all major tissues contain

Chondroblasts

-Cartilage

-secrete gelatinous matrix

Osteoblasts

-bone formation

-secretion of organic fibers and inorganic salts to create crystalline matrix

Mature Fibroblasts

secrete fibers and ground substance of matrix in loose and dense connective tissue, lots of collagen

Red Blood Cells/Erythrocytes

mature resident cell, transport oxygen

White Blood cells/Leukocytes

mature resident cell, immune response; i.e. plasma cells – secrete antibodies/immune system

Platelets/Thrombocytes

blood clotting

Mast cells

produce histamine (chemical that triggers inflammatory response which increases vascular swelling) and attracts more phagocytic cells to the site.

Adipocytes

- fat cells/store triglycerides

- found below skin and around organs

Macrophages

-develop from WBC’s

-move about in connective tissue as scavengers clearing foreign particles

subclasses of connective tissue proper

1. loose (areolar, reticular, adipose)

2. dense (regular, irregular)

cells of loose connective tissue proper

fibroblasts

adipocytes

mast cells

macrophages

cells in dense connective tissue proper

fibroblasts scattered scarcely

extracellular matrix in loose connective tissue proper

reticular includes fibers; areolar is gel-like; adipose has very little

extracellular matrix in dense connective tissue proper

mainly fibers; little else

extracellular fibers in loose connective tissue proper

all three

  - collagen

  - reticular

  - elastic

general features of loose connective tissue proper

-wide variety of locations

-wide variety of functions → support, strength, and elasticity

-store triglycerides

general features of dense connective tissue proper

-dense fibers provide tensile strength

-resist stretching

-found in tendons/ligaments or dermis of skin

subclasses of cartilage connective tissue

hyaline

elastic

fibrocartilage

cells of cartilage connective tissue

chondroblasts

chondrocytes

extracellular matrix of cartilage connective tissue

secreted by chondroblasts

extracellular fibers of cartilage connective tissue

collagen in all; elastic in some

general features of cartilage connective tissue

-provides support and flexibility

-minimizes friction

-forms features and found in joints

subclasses of bone connective tissue

-compact

-spongy (trabecular)

cells of bone connective tissue

osteoblasts

osteocytes

extracellular matrix of bone connective tissue

secreted by osteoblasts

extracellular fibers of bone connective tissue

collagen

general features of bone connective tissue

provides framework; protects organs; supports body

subclasses of liquid connective tissue

-hemopoietic lymph

-hemopoietic blood

cells of hemopoietic lymph connective tissue

macrophages lymphocytes

cells of hemopoietic blood connective tissue

-Thrombocytes (platelets)

-Erythrocytes (RBCs)

-Leukocytes (WBCs)

extracellular matrix of liquid connective tissue (blood + lymph)

plasma

extracellular fibers of hemopoietic blood connective tissue

none

extracellular fibers of hemopoietic lymph connective tissue

reticular

general features of hemopoietic blood connective tissue

-provides transportation, regulation, and protection

- carries oxygen and nutrients to cells

-carries away wastes and carbon dioxide

general features of hemopoietic lymph connective tissue

-plays role in immune defenses

-found in spleen and lymph nodes

skeletal muscle tissue

-striated

-voluntary

-Attached to bones of the skeleton

-function: movements and locomotion

cardiac muscle tissue

-Striated/Intercalated Discs

-involuntary

-walls of heart

-function: pump blood

smooth muscle tissue

-non-striated

-involuntary

-in walls of hollow organs, blood vessels, intestines, urinary tract

-function: change diameter of blood vessels, eliminate waste, move materials along digestive tract

nervous tissue

initiates and transmits nerve impulses to coordinate activities of

the body

muscle tissue

contract to produce voluntary or involuntary movements

two major cells of nervous tissue

neurons + neuroglia

neurons

-specialized to transmit electrical (nerve) impulses

- Sense stimuli → convert stimuli into nerve impulses → signal other nerves, muscles, or glands respond

neuroglia

- do not generate or conduct nerve impulses

- smaller than neurons, many times more numerous

Astrocytes (CNS)

-neuroglia

-Help provide proper environment for generation of nerve impulses

-Provide nutrients to neurons

-Take up excess neurotransmitters

-Maintain proper ion balance (Ca 2+ and K+)

Microglial cells (CNS)

-neuroglia

-Engulf invading microbes

-Clear debris of dead cells

Oligodendrocytes (CNS)

-neuroglia
-provide support for surrounding neurons

-produce myelin sheaths around adjacent neuron axons

Ependymal (CNS)

-neuroglia

-Line cavities of the brain filled with CSF

-Forms CSF and aids with its circulation

CSF

cerebral spinal fluid; clear, colorless liquid that cushions, nourishes, and protects the brain and spinal cord

Schwann Cell (PNS)

Produce myelin sheath around axons of PNS neurons

Satellite Cell (PNS)

Form a protective layer around neuron cell bodies in PNS, providing nutritional and metabolic support

organ

two or more tissues, work together to perform a specific function