1. Outer boundary of the cell, which regulates what enters and exits the cell. It is selectively permeable.
Cell membrane

2. This is the jelly-like fluid matrix within the cell
Cytoplasm

3. The organelle that releases energy from stored food molecules
mitochondrion

4. Site of protein synthesis (where proteins are made)
Ribosome

5. Structures within the cell that perform specialized functions
organelles

6. Controls all cell activities, especially growth and reproduction
nucleus

7. Porous double membrane that separates the nucleus from the cytoplasm
Nuclear envelope

8. Network of protein filaments that helps the cell to maintain its shape
cytoskeleton

9. Genetic material that is found in the nucleus of a nondividing cell
Chromatin

10. Compact form of DNA and protein in the nucleus of a cell about to divide
Chromosome

11. Rough endoplasmic reticulum
Set of tubular passageways involved with the transport of proteins; it has many ribosomes attached and connects the nucleus to the cell membrane
Rough endoplasmic reticulum

12. Non-living layer that surrounds a plant cell and provides protection and support
Cell wall

13. Tubular structures found only in animal cells that are involved in cell division
Centrioles

14. Storage sacs that store food, water, salts and other materials
Vacuoles

15. Stack of flattened membranes that processes and packages proteins to be secreted out of the cell
Golgi apparatus

16. Organelles that contain powerful digestive enzymes that break down substances to be used by the cell as well as toxic materials
Lysosome

17. Site of photosynthesis in the plant cell
Chloroplast

18. Smooth endoplasmic reticulum
Tubular passageways that have few or no ribosomes attached and is the site of lipid synthesis
Smooth endoplasmic reticulum

19. Tail-like structure found in prokaryotes and some animal cells; used for cell movement
flagella