Chapter 3

Question 1

Three basic human cells

Answer 1

Plasma membrane
Cytoplasm
Nucleus

Question 2

Plasma membrane

Answer 2

flexible outer boundary

Question 3

Cytoplasm

Answer 3

intracellular fluid outer organelles

Question 4

Nucleus

Answer 4

DNA containing control center

Question 5

What is the major component of the plasma membrane

Answer 5

phospholipid bilayer

Question 6

Cell junctions

Answer 6

Tight
Desmosomes
Gap

Question 7

Tight Junctions

Answer 7

impermeable, form continuous seals around the cell prevent molecules from passing between cells

Question 8

Desmosomes

Answer 8

Anchoring, bind adjacent cells together like molecular Velcro and help keep cells from tearing apart

Question 9

Gap Junctions

Answer 9

communicate, allow ions and small molecules to pass from cell to cell, in heart cells and embryonic cells

Question 10

Passive transport

Answer 10

no energy is required

Question 11

simple

Answer 11

very small molecules that can pass through membrane or channels, lipid-soluble and nonpolar substances

Question 12

Facilitated

Answer 12

larger, non-lipid soluble or polar molecules can cross the membrane but only with assistance of carrier molecules

Question 13

Osmosis

Answer 13

movement of solvent, not molecules

Question 14

moving down a concentration gradient

Answer 14

natural movement of molecules from areas of high concentration to areas of low concentration

Question 15

Osmolarity

Answer 15

measure the concentration of the total number of solute particles on solvent

Question 16

Isotonic

Answer 16

has equal balance as osmolarity inside the cell, volume unchanged

Question 17

Hypertonic

Answer 17

higher osmolarity resulting in cell shrinking

Question 18

Hypotonic

Answer 18

lower osmolarity resulting in cell swelling

Question 19

Hydrostatic pressure

Answer 19

outward pressure exerted on cell side of membrane caused by increased in volume of cell to osmosis

Question 20

Osmotic pressure

Answer 20

inward pressure due to tendency water to be pulled into a cell with higher osmolarities

Question 21

Active membrane transport

Answer 21

have Active transport and vascular transport both require ATP to move solutes across a plasma membrane:
Solute is too large for channels, or
Solute is not lipid soluble, or
Solute is not able to move down concentration gradient

Question 22

Antiporter

Answer 22

Transport one substance into cell while transporting a different
substance out of cell

Question 23

symporters

Answer 23

transport two different substances in the same direction

Question 24

primary active transport

Answer 24

Required energy comes directly from ATP hydrolysis ->Energy from hydrolysis of ATP causes change in shape of transport protein->
Shape changes cause solutes (ions) bound to protein to be pumped across
membrane

Question 25

secondary active transport

Answer 25

Required energy is obtained indirectly from ionic gradients created by primary active transport

Question 26

Vesicular active transport

Answer 26

involves transport of large particles, macromolecules, and fluids across membrane in membranous sacs called vesicles

Question 27

Exocytosis

Answer 27

transport out of cell

Question 28

Transcytosis

Answer 28

transport into, across, and out of cell

Question 29

vesicular trafficking

Answer 29

transport from one area or organelle in cell to another

Question 30

Endocytosis

Answer 30

involves protein-coated vesicles being pulled in must bind to its unique receptor once inside: fuse with lysosome or transcytosis

Question 31

Phagocytosis

Answer 31

"Cell eating" pseudopods form and flow around solid particles being engulfed, forming a vesicle is pulled into cell

Question 32

Pinocytosis

Answer 32

"Cell drinking" a fluid phase, plasma membrane enfolds bringing extracellular fluid and dissolved solutes inside cell membrane

Question 33

Receptor- mediated endocytosis

Answer 33

involves endocytosis and transcytosis of specific molecules, bind to a membrane-bound receptor

Question 34

Histones

Answer 34

have an effect on DNA can help regulate gene expression

Question 34

Nucleus envelope

Answer 34

double membrane, separates nucleoplasm from cytoplasm

Question 34

Nucleolus

Answer 34

Dense collection of RNA and proteins site of ribosome production

Question 35

Chromatin

Answer 35

fibers of relaxed DNA and proteins, stores info for synthesis of proteins

Question 36

Mitochondria

Answer 36

"Powerhouse" produces most of cell energy ATP cellular respiration. own DNA, RNA, and ribosomes

Question 37

Free Ribosomes

Answer 37

free floating

Question 38

Membrane-bound ribosomes

Answer 38

site of syntheses of proteins to be incorporated into membranes or lysosomes, exported from cell

Question 39

peroxisomes

Answer 39

neutralize toxins, breakdown and synthesis of fatty acids

Question 40

Lysosomes

Answer 40

digest old or unwanted cell sub, bacteria, viruses, and toxins