Ch 3, Sec 2 Looking Inside Cells
Objective: Identify role of cell wall & cell membrane,
role of nucleus, name organelles found in
cytoplasm & describe their functions, describe
how cells differ
Organelles
- small structure inside cell
- carries out specific function in cell
Cell wall
- rigid layer of nonliving material
- surrounds cells of plants & some other organisms
- helps protect & support cell
- made of cellulose
Cytoskeleton
- protein framework inside cell
- gives cells their shape
- found in animal cells & single celled organisms
Cell Membrane
- found in all cells!
- for plant cells, this membrane is located inside
the cell wall
- for animal cells, the membrane forms the
outside boundary that separates cell from
outside environment
- controls what can go in & out of cell!
Nucleus (and everything in it)
- control center of cell, directs all cell’s activities
- large oval structure inside cell
Nuclear Envelope
- outside protective structure of nucleus
- materials pass in & out through nuclear pores
Chromatin
- contain genetic material (instructions for cell)
- thin strands floating in nucleus (cut up
spaghetti)
- stay inside nucleus
Nucleolus
- inside the nucleus
- where the ribosomes are made
Cytoplasm & it’s Organelles
- between cell membrane & nucleus
- clear jello fluid liquid
- constantly moving
Mitochondria
- rod shaped structures
- powerhouses of cell
- convert energy in food molecules to cell
energy
- gives cells their energy to perform
Endoplasmic Reticulum (ER)
- help form proteins and carry material
throughout cell
- like a conveyor belt
Ribosomes
- grainlike bodies
- produce proteins (which tell the cells what
to do)
- some float in cytoplasm, some stay on the
ER
Golgi Body (Golgi Apparatus)
- looks like flat sac’s & tubes
- cell’s mail room
- receives proteins from ER, packages and
distributes to other parts of cell
Chloroplasts
- located in most plants & some other
organisms, not in animal cells!
- capture energy from sunlight to make food
- make leaves green
Vacuoles
- large water filled sacs
- store food & needed material for cell
- also store waste material
- found in all plant cells
- smaller vacuoles found in some animal
cells
Lysosomes
- small, round structures that contain chemicals to
break down certain cell material
Cell Diversity
- cells come in different shapes & sizes,
depending on their function
- some have more of a particular organelle than others