Nucleus and Mitosis

VIBS 443/602

Structure: pancreatic acinar cells

Identification: nucleus, nucleolus, heterochromatin

1. Heterochromatin

2. Nucleus

3. Nucleolus

Pancreas158

Pancreas158

32409

Nuclei with nucleoli

32409

Structure: electron micrograph of hepatocyte (EM 5)

Identification: nuclear envelope, inner and outer membrane, nuclear pores

1. Nuclear envelope

2. Heterochromatin

3. Euchromatin

4. Nuclear pore

EM 2b

nucleuscytoplasm

Structure: electron micrograph

of stomach (EM 15)

Identification: honeycomb nucleolus called nucleonema

1. Nucleus

2. Nucleonema

Structure: freeze etched of small lymphocyte (EM 6)

Identification: fracture plane at one of the nuclear pores jumped from the outer to the inner membrane of the nuclear envelope

1. Inner nuclear membrane

2. Outer nuclear membrane

3. Nuclear pores

Mitosis anaphase102

Mitosis - metaphase102

Mitosis - anaphase102

ORIENTATION

SEGREGATIONALIGNMENT

Three major events in mitosis

CHROMOSOME MOVEMENT

1

2

3

Three contributions Astral microtubules

Structure: intestinal absorptive cells

Identification: nucleus, nucleolus

1. Nuclei

2. Nucleoli

201

152

Intestine crypt mitotic activity.

1. Brush border

2. Interphase nucleus

3. Anaphase

4. Artifact

201

duodenum152

duodenum152

duodenum152

duodenum152

duodenum152

Ileum148

32409

Cells in mitosis

32409

EM 10f: Arteriolar wall; 30,000x.

1. Apical caveolae

2. Collagen

3. Dense bodies

4. Elastic fiber

5. Endothelial cell

6. Nuclear pore

7. RER

EM 19c: Sertoli cell; 13,300x.

1. Golgi

2. Heterophagic vacuole

3. Lipid droplet

4. Microtubule

5. Nuclear pores (cross-section)

6. Sertoli cell

7. Synaptoneural complex

Colchicine treatment – chromosomes do not separate and NE forms around each chromosome due to breakdown of MT.

1. Multinucleated cell

Cytochalasin B treatment-breaks down microfilaments-nucleus activity but cells do not undergo cytokinesis

1. Binucleated cell

2. Nucleolus

Cytochalasin B treatment – chromosomes separate into two normal size nuclei, but the cytoplasm does not split in two

EVENTS IN MITOSIS

CYTOKINESIS

Nucleus and Mitosis