Chapter 6.5 - 6.6

Question 1

Peroxisome

Answer 1

an oxidative organelle that is not part of the endomembrane system but imports proteins primarily from the cytosol

Question 2

Cristae

Answer 2

infoldings in the inner membrane of a mitochondria

Question 3

Mitochondrial matrix

Answer 3

a compartment enclosed by the inner membrane that contains many different enzymes as well as mitochondrial DNA and ribosomes

Question 4

Plastids

Answer 4

a family of closely related plant organelles in which a chloroplast is a part of

Question 5

Thylakoids

Answer 5

a membranous system in the form of flattened, interconnected sacs found in the chloroplast

Question 6

Granum

Answer 6

stacks of thylakoids in a chloroplast

Question 7

Stroma

Answer 7

the fluid outside the thylakoids which contains chloroplast DNA and ribosomes as well as many enzymes

Question 8

Cytoskeleton

Answer 8

a network of fibers extending through the cytoplasm, which play a large role in organizing the structures and activities of the cell, and is composed of 3 types of molecular structures: microtubules, microfilaments, and intermediate filaments

Question 9

Motor proteins

Answer 9

proteins that interact with the cytoskeleton in order to give cells motility

Question 10

Cell motility

Answer 10

encompasses both changes in cell location and more limited momvements of parts of the cell

Question 11

Microtubules

Answer 11

the thickest of the 3 main structures in the cytoskeleton -found in all eukaryotic cells- are hollow rods that shape and support the cell and serve as tracks along which organelles with motor proteins can move

Question 12

Microfilaments

Answer 12

the thinnest of the 3 main structures in the cytoskeleton - are solid rods built from molecules of actin -is present in all eukaryotic cells and forms a 3D network just inside the plasma membrane to help support the cell’s shape

Question 13

Intermediate filaments

Answer 13

fibers with medium sized diameters in the cytoskeleton -found in all eukaryotic cells -bear tension and are more permanent fixtures

Question 14

Centrosome

Answer 14

a region often located near the nucleus that is considered to be a “microtubule-organizing center” in which microtubules grow out of - these microtubules function as compression-resisting girders of the cytoskeleton

Question 15

Centrioles

Answer 15

found in the centrosome of an animal cell and are composed of nine sets of triplet microtubules arranged in a ring

Question 16

Flagella

Answer 16

locomotor appendages that protrude from some cells -beat in an undulating motion that generates force in the same direction as the flagellum’s axis

Question 17

Cilia

Answer 17

locomoter appendages that protrude from some cells- work like oars, with alternation power and recovery strokes generating force in a direction perpendicular to the cilium’s axis

Question 18

Basal body

Answer 18

anchors flagellum and cilia in a cell and is structurally identical to a centriole

Question 19

Dynein

Answer 19

each motor protein extending from one microtubule doublet to the next -is a large protein made of several polypeptides -are respnsible for the bending movements of cilia and flagella -dynein “walking”

Question 20

Actin

Answer 20

a globular protein that make up actin filaments

Question 21

myosin

Answer 21

a protein that acts as a motor protein by means of projections (arms) that “walk” along the actin filaments

Question 22

Pseudopodia

Answer 22

cellular extensions that extend and contract through the reversible assembly of actin subunits in microfilaments and of microfilaments into networks that convert cytoplasm from sol to gel

Question 23

Cytoplasmic streaming

Answer 23

a circular flow of cytoplasm within cells -this speeds the distribution of materials within the cell