Cell Shape & Movement Flashcards Preview

BIO125 > Cell Shape & Movement > Flashcards

Flashcards in Cell Shape & Movement Deck (22)
Loading flashcards...
1
Q

cytoskeleton functions

A

(1) maintain cell shape
(2) structural support
(3) locomotion / movement
(4) transport materials w/in cells

2
Q

types of cytoskeleton

A

(1) actin filaments
(2) intermediate filaments
(3) microtubules

3
Q

actin filament

A
  • motor: myosin
  • subunit: actin
  • strucutre: strands in double helix
  • 5-10% of total proteins in cell

aka microfilaments

4
Q

actin filament functions

A

(1) cell shape
(2) move cells
(3) divide animal cells in two
(4) move organelles & cytoplasm in plants, fungi & animals

5
Q

intermediate filament

A
  • structure: fibers wound into thicker cables

- motor: none (purely strucutral fcn)

6
Q

intermediate filament subunits

A

(1) keratin
(2) lamins
(3) others

7
Q

intermediate filament function

A

(1) cell shape

(2) anchor nucleus & other organelles

8
Q

actin filament types of movement

A

(1) cytokinesis
(2) cytoplasmic streaming
(3) cell crawling
(4) muscle

9
Q

microtubule

A
  • structure: hollow tube
  • motor: dynein & kinesin
  • subunits: ∝-tubuline & β-tubuline
10
Q

microtubule function

A

(1) cell shape
(2) move cells via flagella/cilia
(3) move chromosomes during cell division
(4) assist cell plate formation during plant cell division
(5) move organelles
(6) provide tracks for intracellular transport

11
Q

(+) end in microfilament

A

where things get on

12
Q

(-) end in microfilament

A

where things get off

13
Q

cytokinesis

A

division of cytoplasm to form 2 daughter cells

  • process of cell division
  • typically occurs immediately after nucleus divides in mitosis/meiosis
  • actin-myosin interactions pinch membrane in 2

“cell-moving”

14
Q

cytoplasmic streaming

A

directed flow of cytosol & organelles (that facilitate material distribution) w/in plant & fungal cells

  • occurs along actin filaments
  • actin-myosin interactions move cytoplasm around cell
  • common in large cells
15
Q

cell crawling

A

form of cellular movement

  • involves actin filaments in which the cell produces bulges (pseudopodia) that stick to substrate & pull the cell forward
  • occurs in wide range of organisms & cell types

(aka) amoeboid motion

16
Q

microtubule organizing center (MTOC)

A

any structure that organizes microtubules in cells

- where microtubules originate from

17
Q

centrosome

A

microtubules organizing center (MTOC) for cell’s cytoskeleton

  • structure containing 2 centrioles
  • responsible for spindle apparatus during cell division
  • found only in animal & fungal cells
18
Q

centriole

A

1 of 2 small cylindrical structures found together w/in centrosome near nucleus of eukaryotic cell (not plants)

  • microtubule triplets
  • structurally identical w/ basal body
19
Q

basal body

A

microtubule organizing center for cilia & flagella in eukaryotic cells

  • 9 triplets of microtubules arranged in circle
  • establishes axoneme structures
  • located @ base of microtubules
  • important for axoneme growth
  • foundation for microtubule
20
Q

cilium

A

one of many short, filamentous projections of some eukaryotic cells

  • core = microtubules
  • fcn: move cell & circulate fluid/particles around surface of stationary cell
21
Q

flagellum

A

long, cellular projection that undulates (eukaryotes) or rotates (prokaryotes) to move cell through aqueous environment

  • longer than cilia
  • abundance & pattern of movement diff. than cilia
  • underlying organization identical to cilia
22
Q

axoneme

A

structure found in eukaryotic cilia/flagella

  • responsible for their motion
  • 2 central microtubules surrounded by 9+2 arrangement (nine doublet microtubules)