• The Work of Life

  • What jobs do cells have to do for an organism to live

    • “Breathe”

      • Gas exchange

        • O2 in vs. CO2 out

    • Eat

      • Take in and digest food

    • Make energy

      • ATP

    • Build molecules

      • Proteins

      • Carbohydrates

      • Fats

      • Nucleic acids

    • Removes waste

    • Control internal conditions

      • Homeostasis

    • Respond to external environment

    • Build more cells

      • Growth

      • Repair

      • Reproduction

      • Development

• The Jobs of Cells

  • Make energy

    • Need energy for all activities

    • Need to clean up waste produced while making energy

  • Make proteins

    • Proteins do all the work in a cell, so we need lots of them

  • Make more cells

    • For growth

    • To replace damaged or diseased cells

• Organelles

  • Do the work of the cells

    • Each structure has a job to do

      • Keeps the cell alive

• Cells need power

  • Making energy

    • To fuel daily life and growth

      • Take in food and digest it

      • Take in oxygen

      • Make ATP

      • Remove waste

    • Organelles that do the work

      • Cell membrane

      • Lysosomes

      • Vacuoles and vesicles

      • Mitochondria

• Cell Membrane

  • Function

    • Separates cell from outside

    • Controls what enters or leaves cell

    • Recognizes signals from other cells

      • Allows communication between cells

  • Structure

    • Double layer of fat

      • Phospholipid bilayer

    • Receptor molecules

      • Proteins that receive signals

• Lysosomes

  • Function

    • Digest food

      • Used to make energy

    • Clean up and recycle

      • Digest broken organelles

  • Structure

    • Membrane sac of digestive enzymes

• Mitochondria

  • Function

    • Make ATP energy from cellular respiration

  • Structure

    • Double membrane

• Plants Make Energy in Two Ways

  • Mitochondria

    • Make energy from sugar and oxygen

      • Cellular respiration

  • Chloroplasts

    • Make energy and sugar from sunlight

      • Photosynthesis

• Proteins

  • Making proteins

    • To run, the cell needs to

      • Read genes

      • Build proteins

        • Structural proteins

Muscle fibers

Hair

Skin

Claws

• Enzymes

Speed up chemical reactions

• Signals

Hormones

• Receptors

  • Organelles

    • Nucleus

    • Ribosomes

    • Endoplasmic reticulum

      • ER

    • Golgi apparatus

• Nucleus

  • Function

    • Control center of the cell

    • Protects DNA

      • Instructions for building proteins

  • Structure

    • Nuclear membrane

    • Nucleolus

      • Ribosome factory

    • Chromosomes

      • DNA

• Ribosomes

  • Function

    • Protein factories

    • Read instructions to build proteins from DNA

  • Structure

    • Some free in cytoplasm

    • Some attached to ER

• Endoplasmic Reticulum

  • Function

    • Works on proteins

      • Helps complete the protein after ribosome builds them

    • Makes membranes

  • Structure

    • Rough ER

      • Ribosomes attached

      • Works on proteins

    • Smooth ER

      • Makes membranes

• Golgi Apparatus

  • Function

    • Finishes, sorts, labels, and ships proteins

    • Ships proteins in vesicles

  • Structure

    • Membrane sacs

• Cell Reproduction

  • Making more cells

    • Copy DNA

    • Make extra organelles

    • Divide the new DNA and new organelles between two new “daughter” cells

  • Organelles

    • Nucleus

    • Centrioles

• Centrioles

  • Function

    • Help coordinate cell division

      • Only in animal cells

  • Structure

    • One pair in each cell