CYTOLOGY

Question 1

Define Cytoplasm

Answer 1

aqueous medium in which various organelles are suspended

Question 2

What do nuclei contain?

Answer 2

DNA

Question 3

define endocytosis

Answer 3

(out –> in) uptake of material through the plasma membrane

Question 4

define exocytosis

Answer 4

(in –> out) removal of material thorugh the plasma membrane

Question 5

What are the 2 types of endocytosis

Answer 5

1. Pinocytosis
2. Receptor-mediated endocytosis

Question 6

define pinocytosis

Answer 6

the ingestion of liquid into a cell by the budding of small vesicles from the cell membrane

Question 7

define receptor-mediated endocytosis

Answer 7

the molecule interacts with a specific binding protein, a receptor and is then imported

Question 8

What is the difference between secretion and excretion?

Answer 8

secretion: realease of useful products
excretion: release of waste products

Question 9

What kind of charge does Eosin dye hold? What charge does it bind to?

Answer 9

holds negative charge. binds to positively charged proteins, i.e. acidophilic proteins (acid loving)

Question 10

what color does eosin stain cellular structures?

Answer 10

pink/red

Question 11

What kind of charge does hematoxylin dye hold? What kind of charge does it bind to?

Answer 11

Holds a positive charge. binds to negatively charged DNA and RNA ie. basophilic (base-loving) structures.

Question 12

What color does Hematoxylin stain cellular structures?

Answer 12

blue/purple

Question 13

Define chromatin

Answer 13

a complex of DNA and histones (positively charged)

Question 14

Define euchromatin
What color does it stain with H&E?

Answer 14

Chromatin is spread out- hightly active cells. active transcription.

Stains lightly basophilic (light blue)

Question 15

Define heterochromatin
What color does it stain with H&E?

Answer 15

Chromatin more condensed. Less active cells. Less active transcription.

Stains strongly basophilic (dark blue)

Question 16

What are the two types of ribosomes?

Answer 16

1. free polyribosomes
2. ribosomes bound to RER

Question 17

What color does the RER stain? Why?

Answer 17

Basophilic due to the presence of rRNA (very negative) bound to ribosomes

Question 18

What are the 2 main functions of the RER?

Answer 18

1. protein synthesis
2. post-translational modification of newly synthesized proteins to prep them for export

Question 19

Proteins that are destined for secretion/export and made on the _?

Answer 19

RER

Question 20

Identify A, B and C

Answer 20

A. euchromatin
B. nucleolus
C. heterochromatin

Question 21

Does the smooth ER have ribosomes?

Answer 21

No

Question 22

What is the name of the light-stained section circles in blue? Why does it stain light?

Answer 22

The Negative Golgi Complex.
Less proteins, more lipids = light stain

Question 23

What are the 4 main phases of mitosis?

Answer 23

PMAT
(Prophase, Metaphase, Anaphase, and Telophase)

Question 24

What is happening during prophase of mitosis?

Answer 24

Chromosomes condense into pairs of sister chromatids

Question 25

What is happening during metaphase of mitosis?

Answer 25

Chromosomes condense to their most compact state on the metaphase plate in the middle of the cell

Question 26

What is happening during anaphase of mitosis?

Answer 26

Sister chromatids separate from eachother and migrate to toward opposite poles

Question 27

What is happening during telophase of mitosis?

Answer 27

a constriction develops and division into two cells begins

Question 28

A. Identify the organelle. List one function associated with this organelle.
B. Identify the organelle. List one function associated with this organelle.

Answer 28

A. Golgi complex. Its function includes post-translational modification and protein packaging.
B. Mitochondrion. It produces ATP.

Question 29

1. Identify the organelle shown in A.
2. Identify the organelle shown in B.

Answer 29

1. RER
2. Mitochondrion (cut in cross-section).