cell histology

Question 1

epithelial tissue

Answer 1

tissue that covers the external or internal surface of organs
three cell types: squamous, cuboidal and columnar
- stratified has many layers = protection from mechanical/chemical stress

Question 2

muscle tissue

Answer 2

composed of cells specialized for contraction
elongated cells referred to as muscle fibers
fibers are parallel which aligns the forces of contraction
- enables the muscles to change their shape and become shorter/thicker

Question 3

connective tissues

Answer 3

connect and support different parts of the body; provide strength; store chemicals
lots of variability: bone, blood, fat, …
- specialized cells
- matrix surrounding cell includes extracellular protein fibers (collagen, elastin) and fluid (ground substance)

Question 4

nervous tissue

Answer 4

tissues specialized for rapid communication via nerve impulses which travel over nerve cells

Question 5

stratified squamous epithelium (epithelial tissue)

Answer 5

(esophagus) made up of layers:
- free surface
- oldest squamous cells
- connective tissue
- youngest squamous cells
- basement membrane

Question 6

loose areolar (connective tissue)

Answer 6

• connects epithelium to underlying muscle layer; provides pathways for blood, lymph, nerves and ducts
• contain protein fibers that act as structural supports, cells that produce the fibers (fibroblasts) and an extensive network of capillaries (entry points for absorbed nutrients)

Question 7

blood (connective tissue)

Answer 7

has three distinct layers: erythrocytes, buffy coat (leukocyts and thrombocytes), plasma

Question 8

erythrocytes

Answer 8

transport oxygen in blood, most abundant cells in blood, have lost their nucleus, packed with hemoglobin (protein that makes blood red)

Question 9

leukocytes

Answer 9

have dark purple-staining nucleus (which may be a single structure or divided into lobes; cytoplasm may possess different granules), larger than erythrocytes, part of body’s immune system, some are pagocytic (eat invading organisms)

Question 10

thrombocytes

Answer 10

small purple particles often in clusters, are fragments of cells essential for blood clotting

Question 11

plasma

Answer 11

watery matrix that contains dissolved proteins, normally has no insoluble fibers, contains many soluble chemicals

Question 12

nervous tissue cells

Answer 12

nerve cells are called neurons (made of dendrites, axon and axon terminal)
neurons are typically composed of a nerve cell body and of nerve fibers

Question 13

axons

Answer 13

nerve cell fibers that carry nerve impulse away from nerve cell body

Question 14

dendrites

Answer 14

nerve cell fibers that receive impulses and conduct them to nerve cell body

Question 15

neuroglia

Answer 15

part of nerve tissue that supports neurons but does not conduct impulses

Question 16

skeletal muscle tissue

Answer 16

responsible for voluntary muscle movement, present in the upper third of the esophagus

• cells are long
• contraction fibers: myosin and actin
• nuclei visible as dark elongated structures on periphery of fibers