AP Biology Tour of the Cell

AP Biology Draw 9 boxes on a piece of paper  In each box you will be writing an answer to questions found in this lesson.  Write your answers in full sentences.  If you would like to write your answers in Cornell style, feel free.  When you have completed the notes turn your paper into the purple box.  Be sure to put you name on your paper before turning it in.

AP Biology Discuss with your partner everything you know about cells

AP Biology Prokaryote bacteria cells Types of cells Eukaryote animal cells Eukaryote plant cells

AP Biology Minimize competition between organelles

AP Biology

 Compare and contrast prokaryotic and eukaryotic cells in box #1

AP Biology Why organelles?  Specialized structures  specialized functions  cilia or flagella for locomotion  Containers  partition cell into compartments  create different local environments  separate pH, or concentration of materials  distinct & incompatible functions  lysosome & its digestive enzymes  Membranes as sites for chemical reactions  unique combinations of lipids & proteins  embedded enzymes & reaction centers  chloroplasts & mitochondria mitochondria chloroplast Golgi ER

AP Biology Why organelles? There are several reasons why cells evolved organelles. First, organelles can perform specialized functions. Second, membrane bound organelles can act as containers, separating parts of the cell from other parts of the cell. Third, the membranes of organelles can act as sites for chemical reactions. Organelles as specialized structures An example of the first type of organelle is cilia, these short filaments act as "paddles" to help some cells move. Organelles as Containers Nothing ever invented by man is as complex as a living cell. At any one time hundreds of incompatible chemical reactions may be occurring in a cell. If the cell contained a uniform mixture of all the chemicals it would not be able to survive. Organelles surrounded by membranes act as individual compartments for these chemical reactions. An example of the second type of organelle is the lysosome. This structure contains digestive enzymes, these enzymes if allowed to float free in the cell would kill it. Organelle membranes as sites for chemical reactions An example of the third type of organelle is the chloroplast. The molecules that conduct the light reactions of photosynthesis are found embedded in the membranes of the chloroplast.

AP Biology  To the person net to you three reasons why we have organelles.  Write your answer in box #2

AP Biology Cells gotta live!  What jobs do cells have to do?  building proteins  proteins control every cell function  make energy  for daily life  for growth  build more cells  growth  reproduction  repair

AP Biology  Describe the three jobs of the cell In box #3

AP Biology DNA Why study protein production? cells proteins organism Repeat after me… DNA gets the glory, but Proteins do all the work!

AP Biology Building Proteins  Organelles involved  nucleus  ribosomes  endoplasmic reticulum (ER)  Golgi apparatus  vesicles nucleusribosomeER Golgi apparatus vesicles The Protein Assembly Line

AP Biology DNA RNA ribosomes endoplasmic reticulum vesicle Golgi apparatus vesicle protein on its way! protein finished protein Making Proteins TO: nucleus TO:

AP Biology proteins transport vesicle Golgi apparatus vesicle smooth ER rough ER nuclear pore nucleus ribosome cell membrane protein secreted cytoplasm Making proteins Putting it together…

AP Biology  Describe protein synthesis to the person next to you. Read the textbook (page 123) to find more information about the structure and function of the following organelles: -nucleus, ER, Golgi apparatus,ribosome, and vacuole

AP Biology One of these is not like the others… Explain why in box # 4 Nucleus ER Golgi Vesicles

AP Biology Cells gotta live!  What jobs do cells have to do?  make proteins  proteins control every cell function  make energy  for daily life  for growth  build more cells  growth  reproduction  repair ATP

AP Biology Cells need power!  Making energy  take in food & digest it  take in oxygen (O 2 )  make ATP  remove waste ATP

AP Biology Lysosomes  Function  little “stomach” of the cell  digests macromolecules  “clean up crew” of the cell  cleans up broken down organelles  Structure  vesicles of digestive enzymes only in animal cells Christian de Duve 1960 | 1974 Where old organelles go to die!

AP Biology Lysosomal enzymes  Lysosomal enzymes work best at pH 5  organelle creates custom pH  how?  proteins in lysosomal membrane pump H + ions from the cytosol into lysosome  why?  enzymes are very sensitive to pH  why?  enzymes are proteins — pH affects structure  why is this an adaptation: digestive enzymes which function at pH different from cytosol?  digestive enzymes won’t function well if some leak into cytosol = don’t want to digest yourself!

AP Biology But sometimes cells need to die…  Lysosomes can be used to kill cells when they are supposed to be destroyed (recycling an organisms organic material)  some cells have to die for proper development in an organism  apoptosis  “auto-destruct” process  lysosomes break open & kill cell  ex: tadpole tail gets re-absorbed when it turns into a frog  ex: loss of webbing between your fingers during fetal development  ex: self-destruct of cancerous cell

AP Biology  Describe the structure and function of the lysosome in box #5

AP Biology Fetal development 15 weeks 6 weeks syndactyly

AP Biology When things go wrong…  Diseases of lysosomes are often fatal  digestive enzyme not working in lysosome  picks up biomolecules, but can’t digest one  lysosomes fill up with undigested material  grow larger & larger until disrupts cell & organ function  lysosomal storage diseases  more than 40 known diseases  example: Tay-Sachs disease build up undigested fat in brain cells

AP Biology One of these is not like the others… Explain why in box #6 Lysosomes Digestion Apoptosis Enzymes

AP Biology From food to making Energy  Cells must convert incoming energy to forms that they can use for work  mitochondria: from glucose to ATP  chloroplasts: from sunlight to ATP & carbohydrates  ATP = immediate energy  carbohydrates = stored energy + ATP

AP Biology Mitochondria & Chloroplasts  Important to see the similarities  transform energy  generate ATP  double membranes = 2 membranes  Internal and external membrane Lynn Margulis U of M, Amherst

AP Biology Membrane-bound Enzymes glucose + oxygen  carbon + water + energy dioxide C 6 H 12 O 6 6O 2 6CO 2 6H 2 OATP  +++  semi-autonomous organelles  move, change shape, divide  internal ribosomes, DNA & enzymes

AP Biology Membrane-bound Enzymes + water + energy  glucose + oxygen carbon dioxide 6CO 2 6H 2 O C 6 H 12 O 6 6O 2 light energy  +++

AP Biology Mitochondria are everywhere!! animal cells plant cells

AP Biology  Compare and contrast the functions of the mitochondria and the chloroplast in box #7

AP Biology Cells gotta live!  What jobs do cells have to do?  building proteins  proteins control every cell function  make energy  for daily life  for growth  build more cells  growth  reproduction  repair

AP Biology Cytoskeleton  Function  structural support  maintains shape of cell  provides anchorage for organelles  protein fibers microfilaments, intermediate filaments, microtubules  motility  cell locomotion  cilia, flagella, etc.  regulation  organizes structures & activities of cell

AP Biology  actin  microtubule  nuclei Cytoskeleton

AP Biology  Describe how the cytoskeleton helps the cell in box #8

AP Biology Centrioles  Cell division  in animal cells, pair of centrioles organize microtubules  guide chromosomes in mitosis

AP Biology One of these is not like the others… explain your answer in box #9 Cytoskeleton Support Motility Reproduction

AP Biology Watch the following videos about the cell