Chapter 3: The Cellular Level Of Organization

Question 1

Ion channel (integral)

Answer 1

Forms a pore through which a specific ion can flow through

Question 2

Carrier (integral)

Answer 2

Transports a specific substance across membrane by undergoing a change in shape

Question 3

Receptor (integral)

Answer 3

Recognizes specific ligand & alters cells function in some way

Question 4

Enzyme (integral & peripheral)

Answer 4

Catalyze reaction inside or outside of cell

Question 5

Linker (integral & periperal)

Answer 5

Anchors filaments inside & outside the plasma membrane, providing structural stability & shape for the cell

Question 6

Cell identity marker (glycoprotein)

Answer 6

Distinguishes your cells from anyone else’s

Question 7

Selective permeability

Answer 7

Permit some substances to pass more readily than others

Question 8

Passive process

Answer 8

Movement of substance down concentration gradient until equilibrium is reaches - don’t require energy in ATP

Question 9

Diffusion P

Answer 9

Movement of molecules or ions down a concentration gradient due to their kinetic energy until they reach equilibrium

Question 10

Facilitated diffusion P

Answer 10

Move substance down concentration gradient through the lipid bilayer by transmembrane proteins that function as channels or carriers

Question 11

Simple diffusion P

Answer 11

Movement of substance drown concentration gradient through the lipid bilayer of the plasma membrane without help of membrane transport proteins

Question 12

Osmosis P

Answer 12

Move water molecules across a selectively permeable membrane from an area of higher to lower water concentration until equilibrium is reached

Question 13

Active processes

Answer 13

Movement of substances against a concentration gradient - requires cellular energy in form of ATP

Question 14

Active transport A

Answer 14

Cell expands energy to move a substance across the membrane against its concentration gradient by transmembrane proteins that function as carriers

Question 15

Primary active transport A

Answer 15

Substance moves across the membrane against its concentration gradient by pumps (carriers) that use energy supplied by hydrolysis of ATP

Question 16

Secondary active transport A

Answer 16

Coupled active transport of 2 substances across the membrane using energy supplied by NA+ or H+ concentration gradient maintained by primary active transport pumps

Question 17

Transport in vesicles A

Answer 17

Substances move into or out of cells in vesicles that bud from plasma membrane - requires energy supplied by ATP

Question 18

Receptor-mediated endocytosis A

Answer 18

Ligand-receptor complexes trigger unfolding of a clathrin-coated pit that forms a vesicle containing ligands

Question 19

Endocytosis

Answer 19

Movement of substances into a cell in vesicles

Question 20

Phagocytosis A

Answer 20

“Cell eating” - movement of a solid particle into a cell after pseudopods engulf it to form a phagosome

Question 21

Bulk-phase endocytosis

Answer 21

“Cell drinking” - movement of ectracellular fluid into a cell by unfolding of plasma membrane to form vesicle

Question 22

Exocytosis A

Answer 22

Move substances out of a cell in secretory vesicles that fuse with the plasma membrane & relase their contents into the extra cellular fluid

Question 23

Transcytosis

Answer 23

Movement of a substance through a cell as a result of Endocytosis on one side & exocytosis on the opposite side

Question 24

Organelles

Answer 24

Specialized structures with characteristic shapes

Question 25

Centrosome

Answer 25

Pair of centrioles plus pericentriolar matrix

Question 26

Cilia & flagella

Answer 26

Motile cell surface projections that contains 20 microtubules & a basal body

Question 27

Ribosome

Answer 27

Composed of 2 subunits containing ribosomal RNA & proteins - may be free in cytosol or attached to rough ER

Question 28

ER

Answer 28

Membranous network of flattened sacs or tubules - rough ER is covered by ribosomes & is attached to the nuclear envelope

Question 29

Golgi complex

Answer 29

3-20 flattened membranous sacs called saccules - structurally & functionally divided into entry face, medial saccules & exit face

Question 30

Lysosome

Answer 30

Vesicle formed form golgi complex - contains digestive enzymes

Question 31

Proteasome

Answer 31

Tiny barrel-shaped structure that contains proteases

Question 32

Peroxisome

Answer 32

Vesicle containing oxidase & catalase - new proxisomes bud from pre-existing ones

Question 33

Mitochondrion

Answer 33

Consists of an external & internal mitochondrial membrane, mitochondrial crustaceans & mitochondrial matrix

Question 34

3 main parts of cell

Answer 34

Plasma membrane, cytoplasm, nucleus

Question 35

Glycocalyx:

Answer 35

The sugary coat on the extracellular surface of the plasma membrane - composed of carb proportions of membrane glycolipids & glycoproteins

Question 36

Membrane protein that binds to insulin acts as a:

Answer 36

Receptor