1. Ingenuity Honor’s Biology December 3rd, Monday
Baltimore Polytechnic Institute
Ingenuity Honor’s Biology
December 3rd, Monday
Unit 3: Cells: Nucleus & Endoplasmic reticulum,
Golgi apparatus and vesicles
Insong James Lee, Ph.D.

2. Unit 3: Cells: Nucleus & Endoplasmic reticulum,
December 3rd, Monday
Learning objectives:
Briefly describe the nucleus. What are its functions?
Describe the structure and functions of organelles involved with protein production in cells, including rough ER, smooth ER, ribosomes, Golgi apparatus, and vesicles.
What is the ribosome made up of? What is its function?
What is the difference between the smooth and rough
endoplasmic reticulum.
Unit 3: Cells: Nucleus & Endoplasmic reticulum,
Golgi apparatus and vesicles

3. Unit 3: Cells: Nucleus & Endoplasmic reticulum,
Golgi apparatus and vesicles
Topic slides
Nucleus
2. Logic break
Endomembrane system
(endoplasmic reticulum, golgi apparatus,
vesicles)

4. Nucleus slides 5-15

5. Should we be afraid of the clones?

6. The Nucleus
The nucleus is a small sphere that holds almost all of a eukaryotic cell’s DNA.

7. Structure & Function of Nucleus
Structure: Spherical lipid membrane bound organelle (like cell membrane) that contains DNA.
Functions: Stores DNA, controls cell activity

8. The nucleus is found ONLY in EUKARYOTIC cells.

9. Dolly the Sheep
Dolly was the first clone of an adult mammal ever made.
Dolly was born in 1997, she died a few years later, younger than usual for a sheep.
So what does a cloned sheep have to do with a cell nucleus?

10. When adult animals are cloned, it is by adding a nucleus from a cell to a new egg cell without a nucleus

11. How to Make a Sheep: The Point: Change the nucleus = change the organism
(remove
Nucleus)
(to get the new nucleus into the enucleated cell)
Ewe: female sheep

12. nuclear envelope: A lipid bilayer that surrounds the nucleus nuclear pores: openings in the nuclear envelope

13. Most of the inside of a nucleus is made up of chromatin, which is a mix of DNA and proteins

14. The nucleolus is a small dark part inside a nucleus where ribosomes are made.

15. Find those parts:
Nuclear Envelope
Nuclear Pores
Chromatin
Nucleolus

16. Logic break
TASK: Six classmates raced one another on the playground during recess. Use a matrix (grid) to find out who came in first, second, third, fourth, fifth, and sixth.
1. Alice crossed the finished line immediately after Austin. 2. Aaron finished right between Allen and Abby. 3. Adam won the race. 4. Aaron came in right after the boy who finished second. 5. Austin saw four people finish before him. 6. Allen did not finish fourth.

17. Endomembrane system (in the cytoplasm)
slides 18-30

18. General Cell Terminology
Everything between the nucleus and the cell membrane is called CYTOPLASM.
CYTOPLASM is:
All of the organelles like mitochondria, etc.
The CYTOSOL, which is the aqueous solution everything else floats around in

19. The Endomembrane system
The endomembrane system is a series of folded lipid membranes where protein production takes place. It includes:
The nuclear envelope
The rough and smooth endoplasmic reticulum
The Golgi bodies
Vesicles
PROKARYOTES have NO INTERNAL MEMBRANES. Protein production occurs in the cytoplasm

22. The Endoplasmic Reticulum
Structure: The endoplasmic reticulum is a large series of folded membranes attached to the outside of the nucleus.
Function: Freshly made proteins travel into the lumen of the ER and gets folded and processed within the ER.

23. Two Parts of the ER
The first part has RIBOSOMES attached to it, and is therefore called the ROUGH endoplasmic reticulum.
The second part has no ribosomes and is called the SMOOTH endoplasmic reticulum.
The function of the smooth ER is to produce new lipids for vesicles and membranes.

24. About those SUPER IMPORTANT ribosomes…
Very important function:
RIBOSOMES MAKE PROTEINS!
Structure:
Made up of many proteins and three pieces of rRNA combined

25. More on Ribosomes in the Future…
We’ll learn more about how ribosomes make proteins when we study molecular genetics. The ribosome basics:
Made up of rRNA and proteins.
millions per cell.
Use the information in mRNA to build proteins from amino acids.
Found in all cell types.

27. Rough then Smooth The rough ER is where proteins are built.
The smooth ER has several functions
Most importantly:
Lipid synthesis (for membranes)
Home to many enzymes.

29. Golgi apparatus Structure: folded membranes
Function: Proteins are modified
folded into correct conformations & quarternary structures
Modified chemically
Addition of chemical groups (e.g. heme in hemoglobin, etc.)
Modified amino acids
label proteins so they get delivered to the right places.
What might they be labeled with?

30. Protein Production Smooth Endoplasmic Reticulum Transport Vesicle
Amino
Acids
Rough
Endoplasmic
Reticulum
Outgoing
Transport
Vesicles
Golgi
Apparatus
mRNA
Ribosome
Transport
Vesicles
Nucleus
(DNA)