Cell Organelles and their Functions. Chapter 4 Section 2

Transcription

1 Cell Organelles and their s Chapter 4 Section 2

2 1. Cell Membrane A phospholipid bilayer around the cell that contains proteins and other markers Separates the cell from its environment Secretes materials out of the cell A selectively (semi) permeable membrane that recognizes friendly and enemy objects and allows some materials to enter

3 2. Mitochondria Large organelles that contain their own DNA Has a bilayer membrane: a smooth outer membrane and very folded inner membrane (cristae)

4 2. Mitochondria Releases energy in food into a form the cell can use which is called ATP (cellular respiration) ATP is the currency of energy that cells use Parts of the body that use a lot of energy will have a lot of mitochondria (muscle cells) Because the mitochondria has its own DNA, it can reproduce itself.

5 3. Ribosomes Each cell has 1000 s of ribosomes which are little spheres A ribosome contains a protein connected to some RNA. Ribosomes don t have membranes Protein Synthesis What is the function of nucleic acids?

6 4. Endoplasmic Reticulum ER A membrane system of folded sacs and tunnels When it is covered with lots of ribosomes= rough ER When it lacks ribosomes= smooth ER

7 4. Endoplasmic Reticulum ER The place where the ribosomes assemble their proteins Intercellular highways: where materials can move from one part of the cell to another.

8 5. Golgi Apparatus A system of flattened sacs & membranes that emerge from the ER Modifies the proteins made in the ER so they can be put into packages and exported from the cell

9 6. Vesicles Little sacs that emerge from the Golgi apparatus The transport passage of materials within the cell

10 7. Lysosomes A sac of very strong enzymes in a double membrane Common in animal, fungi and protist cells, but are rare in plant cells Used to digest food molecules and invaders of the cell Sometime used to self destruct cells suicide sacs

11 8. Nuclear Membrane or nuclear envelope A double membrane Has holes called nuclear pores Holds the DNA safe inside the cell Controls what enters and leaves the nucleus

12 9. Nucleolus A spherical body in the nucleus Makes the ribosomes

13 10. Chromatin A fine strand of DNA coiled around proteins Contains all the information for making proteins Is the inherited information that is given to the offspring during reproduction

14 11. Chromosomes Chromatin that is coiled up tightly during cell division Same as chromatin except that it is coiled up tightly so that it can be separated cleanly into the two daughter cells

15 12. Microfilaments Long threads of protein called actin Used when the cell moves and when a muscle cell contracts

16 13. Microtubules Long, slender tubes of protein Gives structure to the cell so it doesn t collapse on itself During cell division, microtubules are used to pull apart the chromosomes into the new daughter cells

17 14. Cilia Short, hair-like structures that emerge from the cell membrane A cell may have 1000 s The cilia beat in unison or in waves. Cilia are used to move cells e.g. paramecium Cilia move mucus or fluids e.g. over the cells of human trachea and lungs Female reproductive system

18 15. Flagellum A long whip-like structure that emerges from the cell membrane A cell has only 1-2 flagella Whip back and forth to move a cell through fluid (e.g. sperm or Euglena)

19 16. Cell Wall A rigid covering of: Cellulose in plants Gives the cell an internal structure so it doesn t collapse on itself What does an animal cell have to not collapse?

20 17. Vacuoles An fluid-filled sac is usually large in plants Contains one of these materials: Water, enzymes, food particles, or waste

21 18. Plastids (chloroplast) Have a double membrane and their own DNA Some plastids have thylakoids which contain pigments Thylakoids look like stacks of pancakes A chloroplast contains thylakoids which absorb solar energy. Then converts it into chemical energy. makes food

22 19. Centrioles Pair of small cylindrical bodies located near the nucleus in cell division

23 Cell Coloring Mitochondrion (mitochondria) Golgi Body (apparatus) Endoplasmic Reticulum Nuclear Membrane Nucleus/ Nucleolus Ribosomes Lysosome Chromatin Cell Membrane Centriole Vacuole Cell Wall Chloroplast