Question

1. If the job of a plasma cell (a type of immune cell) is to make and secrete antibody proteins, which structure(s) might you find a lot of in these cells?

2. If your body tissues are made up of millions of microscopic cells, why don’t they all just fall apart like grains of sand?

3. Your heart needs a constant supply of energy. Which cellular structure might you find in abundance in heart cells?

4. There are special immune system cells called “macrophages” that travel around your body eating up bacteria and dead cells (“macro” means big, “phage” means eater, so a “macrophage” is literally a “big eater”). Which cellular structure(s) do you think these cells might have in abundance?

5. We know that organisms are made out of cells and that cells are made out of cellular structures. But what are cellular structures made out of? In the table below, check off which type(s) of biomolecules make up the major parts of different cellular structures

Cellular Structure	Proteins	Lipids	Nucleic Acids	Carbohydrates
Nucleus
mitochondrion
Chloroplast
Cell membrane
Smooth endoplasmic reticulum
Rough endoplasmic reticulum
Golgi apparatus
Cell wall
amyloplast
cytoskeleton
ribosome

Answer 1

1. Plasma cells: Rough Endoplasmic reticulum ( protein antibodies are synthesized and folded in this organelle)

2. All the cells are held tightly together within a meshwork of extracellular matrix composed of collagen, proteoglycans etc.

3. Heart cells: Mitochondria (produces energy in the cell)

4. Macrophages: Lysosomes (they are the digestive organelles of the cell, digesting protein lipid carbohydrate etc)

5.

Cellular structure	Proteins	Lipids	Nucleic acid	Carbohydrates
Nucleus			Yes
Mitochondria	Yes
Chloroplast	Yes
Cell membrane		Yes
SER	Yes
RER			Yes
Golgi		Yes
Cell wall				Yes
Amyloplast				Yes
Cytoskeleton	Yes
Ribosome			Yes