Quiz 3

Question 1

Tetrahymena need a lot of ____ to survive

Answer 1

O2

Question 2

Most of the detail of living cells is undetectable by __________

Answer 2

bright-field microscopy,

Question 3

Tetrahymena thermophila

Answer 3

Single celled organism, eukaryotic and belong to protozoans

Contain hair like structures called cilia

Question 4

Cilia

Answer 4

Hair like structures that move in a wave like fashion

Create currents that propel nutrient material into the cytosome

Question 5

Food vacuole

Answer 5

Food particles become enclosed in ____ and pinches off from cytosome and migrated to cell interior

Question 6

Phagocytosis

Answer 6

Vacuole formation that occurs in many unicellular organisms

Question 7

Cell mouth

Answer 7

Cytosome

Question 8

Food vacuoles fuse with ____

Answer 8

Lysosomes

Question 9

Undigested material is discharged from the cell at the ______

Answer 9

Cytoproct

Question 10

Movement of cilia and formation and transport of food vacuoles are dependent on ____

Answer 10

Microtubules

Question 11

Microtubules assembled from

Answer 11

Proteins alpha and beta tubulin

Question 12

Motor protein

Answer 12

Dynein

Question 13

What creates swimming pattern in cilia

Answer 13

Bending of the cilia in alternate rows

Question 14

Tetrahymena have the same structure and function as cilia doing in specialized ____ cells

Answer 14

Human

Question 15

bright-field microscopy

Answer 15

magnified images are created by passing light directly through a specimen and into a system of objective and ocular lenses

Question 16

why is bright-field microscope hard to see things

Answer 16

little contrast between their internal structures and the surrounding water-based environment when they are observed with a bright-field microscope

Question 17

Refractive index

Answer 17

n= c/v

Question 18

why is phase contrast preferred?

Answer 18

Phase-contrast is preferable to bright-field microscopy when high magnifications (400x – 1000x) are needed and the specimen is colorless, or its details are so fine that color does not show up well

Question 19

single greatest advantage of __________, however, is that it does not require the use of toxic chemical stains, making it the best method for observing living cells and tissues

Answer 19

phase-contrast microscopy

Question 20

why are culture flasks marked ‘Tetrahymena’ with red tape never to be washed with soap?

Answer 20

The cells are sensitive to detergent and chemical residues on lab glassware.

Question 21

Tetrahymena need a lot of ___ to survive

Answer 21

O2

Question 22

When Tetrahymena cells are pelleted with a microcentrifuge, why must you resuspend them
soon afterwards

Answer 22

because if they are allowed to stand for any length of time (1 minute or more,)
cells in the center of the pellet will suffocate and die
-cells at the top will swim away into the supernate and will be lost
when it is poured or pipetted off

Question 23

why must you pipette this particular cell gently

Answer 23

Larger cells must be pipetted gently to avoid rupturing their plasma membranes as cells pass through the small opening of the pipette tip

Question 24

What does dynein do

Answer 24

Form multiple cross bridges to connect pairs of Microtubules

Question 25

Why are tetrahymena cultures grown in small volumes in large flasks ?

Answer 25

to provide effective aeration of the media

need a lot of O2 to survive

Question 26

Why fo you need to resuspend Tetrahymena soon after being in microcentrifuge?

Answer 26

Bc if allowed to stand any length of time (1minute or more), cells in the center of the pellet will suffocate and die

Question 27

Why do you need to be gentle with pipetting Tetrahymena cells?

Answer 27

bc they are large cells and need to avoid rupturing plasma membrane as cells pass through small opening of the pipette tip

Question 28

_____ is preferable when high magnifications are needed and specimen is colorless

Answer 28

Phase contrast

Question 29

Greatest advantage of phase contrast

Answer 29

does not require the use of toxic chemical stains, making the best method for observing living cells and tissues

Question 30

refractive index

Answer 30

ratio of the speed of light in a vacuum to its speed in a given medium and is

n=c/v

Question 31

____ refractive structures bend light more than ___ refractive index

Answer 31

Highly, low

Question 32

Phase contrast microscopy

Answer 32

uses variations in refractive index to produce differences in brightness that make transparent structures easy to see

Question 33

Tetrahymena are sensitive to detergent and chemical residues on lab glassware
T/F

Answer 33

T