Cell Structure and Function

Biology 11

Warm up!

A student observed a cell that covered 50% of the high

power field of view. Calculate Actual Size.

If the same student drew a diagram of the cell that measured 10.0cm calculate the Scale of the diagram.

Given:

Low power f.o.v. = 4.4mm

Question: How does the nucleus “control” the cell?

1. Nucleus is full of DNA2. DNA strands have genes3. Nucleolus has RNA4. RNA copies part of the DNA5. That copy is the instructions

to produce proteins6. Proteins are used for most

functions of the cell

Smooth Endoplasmic Reticulum (Smooth E.R.)

Huge surface area for chemical reactions to take place.

Can have different functions depending on the cell type. Examples: Synthesis of lipids Metabolism of carbohydrates Detoxification of drugs / poisons

Smooth E.R.

Lysosomes

Membrane enclosed sacs of digestive enzymes.

These enzymes can digest lipids, proteins, complex carbohydrates and nucleic acids!

Functions: Digest old cell parts Intracellular digestion example: WBC’s Development

Protoplasm

Protoplasm = Cytoplasm + Nucleoplasm

Cytoplasm = Cytosol + Organelles

Q: Why do people with Cystic Fibrosis take digestive enzymes?

A: Cystic fibrosis can cause digestive problems because thick,

sticky mucus affects the function of the pancreas. This mucus blocks the ducts of the pancreas, preventing

pancreatic enzymes from reaching the intestines to aid digestion.

Babies with C.F. may have meconium ileus, a blockage of the intestine - shortly after birth.

Source: http://ghr.nlm.nih.gov/condition/cystic-fibrosis

*F.Y.I. Pancreatic juices include a number of enzymes including peptidases, pancreatic lipase and amylase!

Exit Ticket

Explain how the following cell parts work together: Nucleus DNA Rough ER Ribosome Vesicle Golgi

Golgi

Modifies, stores and transports cell products (mostly protein)

Part of

endo-membrane

system!

Mitochondria

Site of cellular respiration converts chemical energy into ATP (usable energy)

Double membrane organelle, contains own DNA and ribosomes.

Chloroplasts

Contain chlorophyll Site of photosynthesis converts solar

energy into chemical energy Double membrane organelle, contains own

DNA and ribosomes.

Mitochondria & ChloroplastWorking Together

http://www.teachersdomain.org/asset/lsps07_int_cellenergy/

Cytoskeleton

Notes

1. How would you decide if something is living? Can you easily define life?

2. Why is the nucleus nicknamed the “control centre” of the cell? How exactly does it control the cell?

3. Explain the importance of energy to living things. Be sure to mention the three main types of energy in your answer.

4. What is metabolism? Why could you consider this the most important life activity?

5. Explain how the following organelles could work together: cell membrane, lysosome, vesicle, mitochondria and ribosome.

6. How are proteins destined for export from a cell typically modified prior to secretion?

7. A cell is like a small community. Identify five cell parts that have a similar function to parts of your community.

8. List three cell structures that have folded membranes. Explain how the folded membranes help each structure function.

Stem Cell Video

http://www.pbs.org/wgbh/nova/sciencenow/3209/04.html

Explain how the following organelles could work together: cell membrane, lysosome, vesicle, mitochondria and ribosome.