AP Biology AP Biology John D. O’Bryant School of Mathematics and Science September 20, 2012

AP Biology Agenda  Do Now (Quiz)  Cells and Organelles

AP Biology Do Now (Quiz)  1. How many molecules of water are needed to completely hydrolyze a polymer that is 11 monomers long?  A) 12 B) 11 C) 10 D) 9 E) 8

AP Biology Do Now (Quiz)  2. Which of the following statements is false for the class of biological molecules known as lipids?  A) They are soluble in water. B) They are an important constituent of cell membranes. C) They contain more energy than proteins and carbohydrates. D) They are not true polymers. E) They contain waxes and steroids.

AP Biology Do Now (Quiz)  3. Which of the following statements is true regarding the molecule illustrated in Figure 5.3? A) It is a saturated fatty acid. B)A diet rich in this molecule may contribute to atherosclerosis. C) Molecules of this type are usually liquid at room temperature. D) A and B only E) A, B and C

AP Biology Do Now (Quiz)  4. What is the structure shown above?  A) starch molecule B) protein molecule C) steroid molecule D) cellulose molecule E) phospholipid molecule

AP Biology Do Now (Quiz)  5. Which of the following statements is/are true regarding the chemical reaction illustrated in Figure 5.5?  A) It is a hydrolysis reaction. B) It results in a peptide bond. C) It joins two fatty acids together. D) A and B only E) A, B, and C

AP Biology Do Now (Quiz)  6 ) Figure 5.7 best illustrates the  A) secondary structure of a polypeptide. B) tertiary structure of a polypeptide. C) quaternary structure of a protein. D) double helix structure of DNA. E) primary structure of a polysaccharide.

AP Biology Cells & Cell Organelles Doing Life’s Work

AP Biology bacteria cells Types of cells animal cells plant cells Prokaryote - no organelles Eukaryotes - organelles

AP Biology Cell size comparison Bacterial cell Animal cell  micron = micrometer = 1/1,000,000 meter  diameter of human hair = ~20 microns most bacteria  1-10 microns eukaryotic cells  microns

AP Biology Why study cells?  Cells  Tissues  Organs  Bodies  bodies are made up of cells  cells do all the work of life!

AP Biology  What jobs do cells have to do for an organism to live…  “breathe”  gas exchange: O 2 in vs. CO 2 out  eat  take in & digest food  make energy  ATP  build molecules  proteins, carbohydrates, fats, nucleic acids  remove wastes  control internal conditions  homeostasis  respond to external environment  build more cells  growth, repair, reproduction & development The Work of Life ATP

AP Biology  Cells have 3 main jobs  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 The Jobs of Cells Our organelles do all these jobs! ATP

AP Biology Organelles  Organelles do the work of cells  each structure has a job to do  keeps the cell alive; keeps you alive Model Animal Cell They’re like mini-organs!

AP Biology 1. Cells need power!  Making energy  to fuel daily life & growth, the cell must…  take in food & digest it  take in oxygen (O 2 )  make ATP  remove waste  organelles that do this work…  cell membrane  lysosomes  vacuoles & vesicles  mitochondria ATP

AP Biology  Function  separates cell from outside  controls what enters or leaves cell  O 2, CO 2, food, H 2 O, nutrients, waste  recognizes signals from other cells  allows communication between cells  Structure  double layer of fat  phospholipid bilayer  receptor molecules  proteins that receive signals Cell membrane lipid “tail” phosphate “head”

AP Biology cell membrane  cell boundary  controls movement of materials in & out  recognizes signals cytoplasm  jelly-like material holding organelles in place

AP Biology Vacuoles & vesicles  Function  moving material around cell  storage  Structure  membrane sac small food particle vesicle vacuole filled w/ digestive enzymes vesicle filled w/ digested nutrients

AP Biology End 9/20