Chapter 6.5-7.1

Question 1

Cytoskeleton

Answer 1

A network of fibers extending through cytoplasm

Question 2

What are the cytoskeletons functions

Answer 2

1. Plays major role in organizing the structures and activities of the cell 2. Give mechanical support to cell and maintain its shape 3. Manipulate the plasma membrane bending it to form vacuoles or vesicles

Question 3

What 3 types of fibers make up the cytoskeleton?

Answer 3

Microtubules - thickest Microfilaments - thinnest Intermediate filaments - medium

Question 4

Microtubules

Answer 4

Hollow tubes constructed from globular proteins called tubulins Maintenance of cell shape Cell motility Chromosome and organelle movements

Question 5

Microfilaments

Answer 5

Two intertwined strands Make up core of microvilli Maintenance and changes of cell shape Muscle contraction Cytoplasmic streaming Cell motility Cell division

Question 6

Intermediate filaments

Answer 6

Fiberous protein coiled into cables Only found in some animals including vertebrates Maintenance of cell shape *sturdy Anchorage of nucleus and other organelles Formation of nuclear lamina Nucleus cage Permanent framework of entire cell

Question 7

Dimer

Answer 7

A molecule made up of 2 components

Question 8

Centrosomes

Answer 8

A region located near nucleus where microtubules grow

Question 9

Centrioles

Answer 9

A pair of nine sets of triplet microtubules staged in a ring located Within the centrosome

Question 10

Flagella

Answer 10

Cellular extension that contains microtubules Longer and fewer on cell Motion is like a fish tail Can move cell

Question 11

Cilia

Answer 11

Cellular extensions that contain microtubules Lots of them on a cell and smaller Movement like oars on boat Some Also have signal receiving antenna for the cell*

Question 12

How are each flagellum and cilium structured?

Answer 12

A group of microtubules sheathed in an extension of plasma membrane 9 doublets of microtubules are arranged in a ring with 2 single microbes in its center (9+2 pattern) Nonmotile cilia have “9+0”

Question 13

Basal body

Answer 13

Microtubules triplets in a “9+0” pattern Anchors cilia or flagellum in the cell

Question 14

Dyneins

Answer 14

Large motor protien that are attached along each outer microtubule doublet Has two “feet” that “walk” along the microtubules using ATP for energy

Question 15

Myosin

Answer 15

Protein used to cause contraction of muscle cells

Question 16

Pseudopodia

Answer 16

“False foot”

Cellular extensions used to move cell

Question 17

Cytoplasmic streaming

Answer 17

Circular flow of cytoplasm within cells

Question 18

Cell wall

Answer 18

Extra cellular structure of plant cell Protects plant cell Maintains shape and Prevents excessive uptake of water

Question 19

Middle lamella

Answer 19

Thin layer between primary cell walls rich in sticky polysaccharides called pectins which glues cells together

Question 20

(ECM) extra cellular matrix

Answer 20

Animal cells lack walls but do have ECM. Which consists of glycoproteins and other carb containing molecules

Question 21

Collagen

Answer 21

Most abundant glycoprotein in the ECM of most animal cells

Question 22

Fibronectin

Answer 22

ECM glycoprotein. Binds to cell surface receptor called integrins

Question 23

Integrins

Answer 23

Cell surface receptor proteins that are built into plasma membrane Transmit signals between ECM and cytoskeleton

Question 24

Plasmodesmata

Answer 24

Channels that connect plant cells Unify plant into one living continuum Enabling water and small solutes to pass between cells

Question 25

What are the 3 types of cell junctions in animal cells

Answer 25

Tight junction Desmosomes Gap junctions

Question 26

Amphipathic

Answer 26

Has Both hydrophilic and hydrophobic region

Question 27

Integral proteins

Answer 27

Penetrate the hydrophobic interior of lipids bilayer

Question 28

Peripheral proteins

Answer 28

Loosely bound to the surface of the membrane