Cytoskeleton

Question 1

Cytoskeleton

Answer 1

Dynamic network of fibers throughout the cytoplasm

Question 2

Cytoskeleton function

Answer 2

Support, maintains shape, and anchors organelles
Movement
Regulation
Transmits forces from the surface to the interior of the cell (signal)

Question 3

Types of filaments

Answer 3

Microtubules, microfilaments, and intermediate filaments

Question 4

Motor protein function

Answer 4

Use ATP to power movement in interaction with plasma membrane molecules or cytoskeleton tracks, one foot maintaining contact wile the other releases and attaches one step further
Responsible for bending movements of cilia and flagella

Question 5

Motor protein structure

Answer 5

Microtubule doublets held in place by cross linking proteins
Receptor connects motor protein to vesicle for transport

Question 6

Microtubule structure

Answer 6

Hollow tubes made of protein tubulin dimers (globular proteins made of an α-tubulin and a β-tubulin)

Question 7

Microtubule diameter

Answer 7

25nm

Question 8

Microtubule subunit

Answer 8

Tubulin

Question 9

Microtubule function

Answer 9

Cell support (compression resistance)
Cell movement (cilia and flagella)
Chromosome movement in cell division
Organelle movement
Vesicle movement

Question 10

Microtubules grow from…

Answer 10

Centrosomes

Question 11

Centrioles

Answer 11

Cylindrical structures containing 9 sets of 3 microtubules
Exist in perpendicular pairs in the centrosome

Question 12

Cilia and flagella structure

Answer 12

Hair-like structures with 2 central microtubules and an outer 9 sets of 2 microtubules with dynein motor proteins extending from the outer microtubule and walking along the adjacent microtubule
Anchored by a basal body
Surrounded by an extension of the plasma membrane

Question 13

Basal body structure

Answer 13

Cylindrical structures containing 9 sets of 3 microtubules (same as centrioles)

Question 14

Basal body function

Answer 14

To anchor cilia and flagella to the cell

Question 15

Cilia and flagella function

Answer 15

Move the cell or move things past the cell

Question 16

Cilia

Answer 16

Many and short

Question 17

Flagella

Answer 17

Few and long

Question 18

Primary cilia

Answer 18

Nonmotile signal receiving cilia in many vertebrate animal cells

Question 19

Microfilament structure

Answer 19

Solid fibers made of two intertwined strands of actin

Question 20

Microfilament function

Answer 20

Cell support (bearing tension via pulling forces)
Cytokinesis
Cell movement (creeping)
Muscle contraction
Cytoplasmic streaming

Question 21

Microfilament diameter

Answer 21

7nm

Question 22

Microfilament subunit

Answer 22

actin

Question 23

Cytoplasmic streaming

Question 24

Cortical microfilaments

Answer 24

Network of supportive microfilaments just inside the cell membrane that gives the cell its shape and gives the cortex a gel-like consistency

Question 25

Cortex

Answer 25

Outer cytoplasmic layer of the cytoplasm with a gel-like consistency

Question 26

Microvilli

Answer 26

Finger-like projections made of microfilaments that increase a cells surface area

Question 27

Microfilament (actin) interaction with myosin

Answer 27

Myosin and actin filaments driven past each other drawing actin filaments towards each other in order to shorten a muscle cell for contraction

Question 28

Pseudopodia

Answer 28

Microfilament cellular extension that allow for creeping cell movement

Question 29

Intermediate filament structure

Answer 29

Fibrous proteins coiled into cables

Question 30

Intermediate filament function

Answer 30

Cell support (bear tension) Cell adhesion (DESMOSOMES) Hold organelles in place Formation of the nuclear lamina (supporting the nuclear envelope)

Question 31

Intermediate filament diameter

Answer 31

8-12nm

Question 32

Intermediate filament subunit

Answer 32

Various proteins Some are repeating keratin subunits

Question 33

Cell wall structure

Answer 33

Supportive layer outside cell membrane

Question 34

Cell wall function

Answer 34

Cell and organism structural support and protection Prevents excess water uptake and loss

Question 35

Cell walls exist in...

Answer 35

All plants and fungi Many bacteria and protists

Question 36

Plant cell wall structure

Answer 36

Cellulose and other carbohydrates (pectin and hemicellulose)

Question 37

Primary cell wall

Answer 37

First thin cell wall layer Able to stretch

Question 38

Secondary cell wall

Answer 38

Thicker cell wall layer formed afterwards and on the interior of the primary cell wall

Question 39

Middle lamina structure

Answer 39

Made of pectin; highly hydrophilic carbohydrates that take a sticky gelatinous texture in water

Question 40

Middle lamina function

Answer 40

Cement adjacent cells together

Question 41

Cell wall structure (outside in)

Answer 41

Middle lamina, primary cell wall, secondary cell wall, cell membrane

Question 42

Plant cell wall main component

Answer 42

Cellulose

Question 43

Fungi cell wall main component

Answer 43

Chitin

Question 44

Bacteria cell wall main component

Answer 44

Peptidoglycans (netlike sugar and amino acid macromolecule)

Question 45

Archaea cell wall

Answer 45

No peptidoglycans

Question 46

Protist cell wall

Answer 46

Highly variable structure

Question 47

Extracellular matrix structure

Answer 47

Glycoproteins and other carbohydrate containing molecules Integrins Fibronectins Collagen Proteoglycans

Question 48

Extracellular matrix function

Answer 48

Tissue support Tracks for cell movement Cell signaling Coordinating behavior between cells in tissues

Question 49

Integrin

Answer 49

Protein with two subunits embedded in the cell membrane to connect the ECM to the cell Binds to fibronectins in ECM and microfilaments in cortex

Question 50

Fibronectin

Answer 50

One kind of extracellular protein that binds to integrins

Question 51

Plasmodesmata structure

Answer 51

Areas of the cell wall in which the cytoplasm of one cell is directly continuous of that of another Lined by plasma membrane and filled with cytosol

Question 52

Plasmodesmata function

Answer 52

Cell to cell communication Passing macromolecules between cells using

Question 52

Central desmotubule of ER

Answer 52

Tubules running through the plasmodesmata and connecting to the endoplasmic reticulum's of adjacent cells

Question 53

Types of junctions in animal cells

Answer 53

Tight junctions Desmosomes Jap junctions

Question 54

Tight junction structure

Answer 54

Membranes of neighboring cells are fused with the help of proteins

Question 55

Tight junction function

Answer 55

Cell adhesion Holds cells together tightly and forms a seal Prevents leakage of extracellular fluids across a layer of epithelial cells

Question 56

Gap junction structure

Answer 56

Protein channels lined up between cells (similar to plasmodesmata but no membrane lining)

Question 57

Gap junction function

Answer 57

Cell to cell communication

Question 58

Desmosome structure

Answer 58

Plates on the inside of each cell membrane anchored by keratin intermediate filaments

Question 59

Desmosome function

Answer 59

Cell adhesion