1 / 22

Cells

Explore the levels of cellular organization, including atoms, molecules, organelles, cells, tissues, organs, organ systems, and organisms. Learn about the components of cells, such as the nucleus, cytoplasm, cell membrane, cell wall, and various organelles like the endoplasmic reticulum, Golgi apparatus, mitochondria, chloroplasts, and more. Discover the differences between prokaryotic and eukaryotic cells.

jshane
Download Presentation

Cells

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Cells

  2. Levels of cellular organization Atom Molecule Organelle Cell Tissue Organ Organ System Organism

  3. Division of Cells • Eukaryotic Cells • Literally means “True nucleus” • Have a nucleus • Complex Cells • Have membrane-bound organelles • Organisms made of eukaryotic cells are called “eukaryotes” Examples: Animals, Plants, Fungi, Unicellular organisms like paramecium and amoeba

  4. Cellular Components • Cytoplasm • Gel-like substance within the cell where organelles are found • Cytoskeleton • “Cell skeleton” • Network of protein fibers that maintain the shape of cell • Composed of three networks of fibers • Microtubules: largest; hollow tubes made of protein; determine cell shape; scaffolding • Intermediate Filaments: Provide strength of cell • Actin Filaments: smallest; contractile string-like proteins that allow for cell movement

  5. Cellular Components • Cell Membrane • Semi-permeable barrier that encloses the cell • Regulates what enters and exits the cell • Provides protection • Found in all types of cells • Cell Wall • Porous, rigid barrier found surrounding the cell membrane • Adds additional layer of support and protection • Not found in animal cells

  6. Organelles • Nucleus • Houses the genetic material (DNA) needed for replication of the cell • “Control Center” of the cell • Contains the instructions for the creation of proteins (made from DNA) • Exterior: Surrounded by nuclear envelope: double-layered membrane that encloses the DNA; contains nuclear pores: small openings that allow for the passage of molecules between the cytoplasm and the nucleus • Interior: DNA in the form of chromatin (string-like) • Nucleolus: where ribosomes are made; very dense region

  7. Organelles • Endoplasmic Reticulum • A grouping of sac-like structures • Two Types of ER: • Rough ER: contain ribosomes (creating ‘rough’ appearance); involved in the process of protein synthesis • Smooth ER: no ribosomes; involved in lipid synthesis • Ribosomes • Location where proteins are made (protein synthesis)

  8. Organelles • Golgi Apparatus • Looks like a stack of membranes (pancake-like appearance) • Modifies, sorts and packages proteins received from the ER. • Break off from the golgi apparatus; floats freely in the cell or travels to cell membrane where it will eventually exit the cell. • Creation of lysosomes

  9. Organelles • Lysosomes • Contain enzymes necessary for digestion of cell food or waste • Can break down lipids, carbs, proteins • Digest non-functional organelles, ‘cleaning up’ the cell

  10. Organelles • Vacuoles • Sac-like structure responsible for storage of various materials (e.g. water, carbs, proteins, etc.)

  11. Organelles • Mitochondria • The “Powerhouse” of the cell • Convert food energy into energy that is used by the cell itself (for growth, development, movement, etc.) via cellular respiration • ATP (Adenosine Triphosphate) • Complex structure

  12. Organelles • Chloroplast • Site of photosynthesis • Energy from sun is captured and converted into chemical energy • Contain the pigment chlorophyll which absorbs solar energy used in photosynthesis • Responsible for the green color of plants

  13. Organelles • Centrioles • Made of microtubules • Located near nucleus • Organize microtubules within the cytoskeleton prior to cell division

  14. Division of Cells • Prokaryotic Cells • Include Bacteria & Archaea • Literally means “before nucleus” • So-have no nucleus • Lack membrane-bound organelles • Simpler and much smaller than Eukaryotes • Organisms made of prokaryotic cells are called “prokaryotes”

  15. Structure of Prokaryotes • Three basic shapes • Bacilli: rod-shaped bacteria • Cocci: Spherical-shaped bacteria • Spirilla: Spiral-shaped bacteria; flexible

  16. Prokaryotic Cell Parts: Interior Do prokaryotic cells have DNA if they lack a nucleus? • Nucleoid: a region within the cytoplasm of the cell in which the DNA is located; center of the cell (no membrane encloses the DNA) • Cytoplasm • Semifluid, gel-like solution encased within the cell membrane of the cell

  17. Interior • Ribosomes • Made of two subunits (each containing a combination of various proteins and rRNA) which work together to synthesize protein • Located throughout the cytoplasm

  18. External Layers • Cell Membrane • Regulates the entrance and exit of various substances in and out of the cytoplasm • Cell Wall • Provides shape, structure, and support for cell • Glycocalyx • The outermost layer of bacterial cells; gel-like protective layer

  19. External Structures • Flagella • Allows for cell movement • Long, rotating filament that propels the cell forward • Fimbriae • Hair-like bristles located on the external surface of the cell • Allow cells to attach to surfaces • Conjugation Pili • Tube-like structures that allow for bacteria to pass DNA from cell to cell; usually larger and less numerous than fimbriae

More Related