Introduction Audience 10 th grade Biology Students BIOLOGY

Introduction Audience: 10 th grade Biology Students BIOLOGY A – UNIT Cell Biology Objectives: Students will understand the organelles and their specific functions that are inside of eukaryotic cells.

Here we go………… • You are going to be exploring inside the cell. • You are going to learn WHAT is in there and what each organelle DOES!!!

Cell Characteristics • The basic processes necessary for living things to survive are the same for a single cell as they are for a more complex organism. • A single-celled organism has to conduct all life processes by itself. • A multi-cellular organism has groups of cells that specialize to perform specific functions.

Cell Characteristics Cell Organization • In multicellular eukaryotes, cells organize into tissues, organ systems, and finally organisms.

Cell Characteristics • All cells contain: • Genetic material – single circular molecule of DNA in prokaryotes – double helix located in nucleus in eukaryotes • Cytoplasm jelly-like substance that fills the cells interior • Plasma membrane encloses the cell – – phospholipid bilayer

Cell Size • Most cells are relatively small because as size increases, volume increases much more rapidly. – longer diffusion time

Visualizing Cells

Let’s check out the size of cells Check out Cell Sizes • Click on the above site and check out the different sizes of cells.

Lets Take a Quick Second to Review True or False The basic processes necessary for living things to survive are different for a single cell than a more complex organism. TRUE FALSE

CORRECT!!!! Congrats! You got it right!!!

Sorry!! Wrong Answer – Try Again!

Another true and false ? • A single-celled organism has to conduct all life processes by itself. TRUE FALSE

CORRECT!!!! Congrats! You got it right!!!

SORRY Hmmm…. try again!

Review cont. Fill in the blank A multi-cellular organisms has groups of _____ that specialize to perform specific functions. A. Cells B. Atoms C. Molecules

Correct! Cells is the right answer! Great Job!!!

Sorry! Try again…think about what we are learning about today!

Nucleus Stores genetic material Contains DNA site where RNA is made Nucleolus: Chromatin and ribosomal subunits Nuclear envelope: – Double membrane with pores • Largest organelle • BRAIN of the cell – controls protein synthesis • • •

Nucleus

Nucleus Cont. • Go to the site below and check out a virtual cell http: //www. youtube. com/watch? v=f. Iy. Lrp. RDr. B 8

Let’s Review the Nucleus stores _______ • A. genetic material • B. DNA • C. RNA • D. All of the above

Correct! • Sweet!

Sorry!! Wrong Answer – Try Again!

Ribosomes • Ribosomes are RNA-protein complexes composed of two subunits that join and attach to messenger RNA. – site of protein synthesis – assembled in nucleolus

Ribosomes

Ribosomes • Click here For a more in depth reading on Ribosomes, also check out the You Tube video “Bacterial ribosome translating RNA into Protein”

Endoplasmic reticulum – transports materials through the cell • Rough ER - studded with ribosomes – Attached to nuclear membrane – site of protein synthesis and processing • Smooth ER - lacks ribosomes – site of synthesis of phospholipids and the packaging of proteins into vesicles

Endoplasmic reticulum

More on ER…… • http: //www. cellsalive. com/cells/er. htm • Let’s check on cells alive again. . this time we are going to look at endoplasmic reticulum.

Review Which organelle is the site for protein synthesis? a. Nucleus b. Golgi Apparatus c. Ribosome

CORRECT • Awesome Job! You are exactly right. Ribosomes are the site for protein synthesis!

SORRY! Try again!

Review Which endoplasmic reticulum is studded with ribosomes? ROUGH or SMOOTH

CORRECT You are EXACTLY right!! Smooth LACKS ribosomes and the Rough is studded with ribosomes making it appear rough.

SORRY! Try again! Remember what each one looks like.

Golgi apparatus – collection of Golgi bodies • Stacked flattened sacks • Site where cell products are packaged for export • Proteins are modified by being combined with fats or carbohydrates

Golgi apparatus – Vesicles then pinch off from the Golgi body to be secreted (outside the cell) – Involved in the production of lysosomes

Golgi apparatus

Review The Golgi Apparatus is involved in the production of? a. Ribosomes b. Lysosomes c. Endoplasmic Reticulum

CORRECT You are exactly right! The Golgi Apparatus produces lysosomes and is the site where products are packaged for export out of the cell.

Sorry! Try again. Wrong answer.

Lysosomes • vesicles produced by the Golgi apparatus. • Lysosomes contain digestive enzymes and are involved in intracellular digestion of food particles, disease causing bacteria and worn out cell parts

Golgi Apparatus and Lysosomes

Mitochondria ¢ ¢ Powerhouse of the cell" - cellular metabolism Structure- outer and inner membranes, cristae Found in both plant and animal cells Very active cells have more mitochondria

Cell Membrane • controls what enters and leaves the cell • Found in ALL cells • Phospholipid bilayer with transport proteins, and cholesterol (for flexibility)

Which organelle is this? • • Lysosomes Golgi Apparatus Nucleus Cell Membrane

Correct • You are exactly right! The Golgi Apparatus produces lysosomes and is the site where products are packaged for export out of the cell.

Try again • Hint…. a packaging apparatus!

CELLS ALIVE • To give you some time to absorb what you have learned about the organelles, explore Cells. Alive. com and take the quiz on cells.

Almost done…. • Check out http: //www. ibiblio. org/virtualcell/index. htm • It is a virtual cell…. check out all of the organelles…

Great Job Today!!!! • Now you know all of the organelles that make up a cell and what they do.