Lecture Week 1: Chapter 3

Question 1

Cytology

Answer 1

Study of Cells

Robert Hooke

Question 2

Cell Theory

Answer 2

Cells arise only from other cells and every living organism is composed of cells and cell products. Cells are the simplest structural and functional unit of life. All physiological processes of the body are based on cellular activity.

Question 3

Squamous

Answer 3

thin, flat, scaly shape (fried egg), line the esophagous and form the epidermis layer.

Question 4

Cuboidal

Answer 4

squarish-looking in frontal sdctions and about equal in height and width. ex: liver cells

Question 5

Columnar

Answer 5

taller than wide. Inner linging of stkmach abd intestines.

Question 6

Polygonal

Answer 6

irregularly angular shapes with four, five or more sides.

Question 7

Stellate

Answer 7

multiple pointed processes projecting from the body of a cell, starlike. ex: nerve cells.

Question 8

Spheroidal/ovoid

Answer 8

round to oval, egg cells, blood cells

Question 9

Discoidal

Answer 9

disc-shaped, red blood cells

Question 10

Fusiform

Answer 10

spindle-shaped, elongated, thick middle, tapered ends. Smooth muscle cells.

Question 11

Fibrous

Answer 11

long, slender, threadlike. skeletal muscle and axons.

Question 12

Micrometer(μm)

Answer 12

unit of measure for designating cell size. one millionth of a meter, one thousandth of a millimeter. Cells are small so they can diffuse from place to place faster.

Question 13

cyroplasm

Answer 13

fluid between nucleus and surface membrane. crowded with fibers, thbules, passages and compartments. contains Cytoskeleton, organelles,

Question 14

Plasma membrane

Answer 14

cell is surrounded by this, made up of proteins and lipids. function differs from regions of cell. governe interactions with other cells. controls passag eof materials into and out of the cell.

Question 15

cytoskeleton

Answer 15

supportive framework of protein filaments and tubules

Question 16

inclusions

Answer 16

foreign matter or stored cell products

Question 17

cytosol/intracellular fluid

Answer 17

clear gel that embeds the cytoskeleton, organelles and inclusions.

Question 18

extracellular fluid

Answer 18

all body fluids NOT contained in cells. includes blood plasma, lymph, cerebrospinal fluid.

Question 19

Tissue (intersitial) fluid

Answer 19

extracellular fluid located amid the cells.

Question 20

IN SUMMARY: major components of cells

Answer 20

• Plasam membrane
• Cytoplasm
  - Cytoskeleton
  - Organelles
  - Inclusions
  - Cytosol

Question 21

What is the difference between cytoplasm and cytosol

Answer 21

Cytosol (surrounds cell organelles, cytoskeleton, inclusions) is the fluid contained in the cell cytoplasm, cystoplasm is the entire content within the cell membrane.

Question 22

Plasma membrane

Question 23

intracellular face of plasma membrane

Answer 23

side that faces the cytoplasm

Question 24

extracellular face of plasma membrane

Answer 24

side the faces outward

Question 25

Membrane Lipids

Answer 25

membrane made up of an oily film of lipids eith proteins embedded in it.
98% of membrane molecules are lipids.
- 75% phospholipids 
- 20% cholesterol lipids
- 5% glycolipids

Question 26

Phospholipids

Answer 26

arranged in bilayer. keep the mebrane fluid.

Question 27

Cholesterol molecules

Answer 27

found amid phospholipids. interact with phospholipids, hold them, thus stiffening the membrane in spots.

Question 28

Glycolipids

Answer 28

Phospholipids with short carbohydrate chains on the extracellular face of the membrane. contribute to glycocalyx.

Question 29

Membrane proteins

Answer 29

2% of molecules in plasma membrane. larger than lipids, 50% of membrane weight. two broad classes of membrane proteins: transmembrane and peripheral.

Question 30

Transmembrane proteins

Answer 30

pass completely through phospholipid bilayer. hydrophilic and hydrophobic regions. some drift freely (ice cubes) some are anchored to cytoskeleton.

Question 31

Perioheral proteins

Answer 31

do NOT protrude into phospholipid layer, instead adhere to either inner or outer face of the membrane. Inner perioheral proteins are anchored to a transmembrane protein ad well as the cystoskeleton.

Question 32

Functions of membrane proteins

Answer 32

• receptors
• second-messengar systems
• Enzymes
• channel proteins
• carriers
• cell-identity markers
• cell-adhesion molecukes

Question 33

Receptors

Answer 33

binds to chemical messengers such as hormones sent by ither cells

Question 34

Enzyme

Answer 34

breaks down chemical messenger and terminates its effect

Question 35

channel

Answer 35

constantly open and allows solutes to pass onto and out of the cell

Question 36

gated channel

Answer 36

opens and closes to allow solutes through only at certain times

Question 37

cell-identity marker

Answer 37

glycoprotein acting as a cell-identity marker distinguishing the body’s own cells from forgein cells

Question 38

cell-adhesion molecule(CAM)

Answer 38

binds one cell to another

Question 39

Carriers

Answer 39

transmembrane proteins that bind to glucose, electrolyes and other solutes and transfer them to the other side of the membrane. Pumps: type of carrier, consume ATP in the process.

Question 40

Second messenger systems

Answer 40

when a messenger binds to a surface receptor, triggers changes within cell. This produces the SECOND MESSENGER in the cytoplasm. process involves both transmembrane and perioheral proteins.

Question 41

Glycocalyx

Answer 41

external to plasma membrane. fuzzy coating of cells. enables body to distinguish its own healthy cells from transplanted tissues, invading organisms and diseased cells.

Question 42

surface extensions

Answer 42

microvilli, cilia, flagella, pseudopods. aid in absorption, movement and sensory process.

Question 43

microvilli

Answer 43

extension of plasma membrane. increasd cell’s surface area. best for absorption cells (epithelial).

Question 44

brush border

Answer 44

very dense cluster of microvilli, look like a fringe.

Question 45

actin

Answer 45

in some microvilli: bundle of s