Bio11 Notes Cells (New) PDF

#1) Cell Theory  Cell Theory 1) All living things are composed of cells. 2) Cells are the basic units of structure and function in living things. 3) New cells are produced from pre-existing cells.  Contributors to the Cell Theory: 1) Zacharias Jenssen 2) Anton van Leeu...

#1) Cell Theory  Cell Theory 1) All living things are composed of cells. 2) Cells are the basic units of structure and function in living things. 3) New cells are produced from pre-existing cells.  Contributors to the Cell Theory: 1) Zacharias Jenssen 2) Anton van Leeuwenhoek 3) Robert Hooke 4) *Sir Isaac Newton 5) Matthias Schleiden 6) Theodor Schwann 7) Rudolf Virchow 8) Robert Remak #2) Characteristics of Living Things  Criteria to be considered living: 1) Made of one or more cells 2) Reproduce (sexually or asexually) 3) Contain a genetic code (DNA) 4) Grow and develop 5) Obtain and use energy 6) Respond to their environment 7) Evolve over time  1) Made of one or more cells Unicellular – single celled Multicellular – more than one cell e.g. Euglena e.g. Daphnia  2) Reproduce sexually or asexually Sexual reproduction – Asexual reproduction – gamete production and genetically identical cells or fertilization offspring egg and sperm e.g. fission of bacteria 3) Contain a genetic code (DNA) Deoxyribonucleic acid (DNA) function: 1) Controls activities within a cell. 2) Stores and transmits genetic information from one generation to the next.  4) Grow and develop Cells undergo cell division and cell differentiation: cell division: cell differentiation:  5) Obtain and use energy Autotrophs (e.g. plants) Heterotrophs (e.g. bear) cannot produce their own food. produce their own food.  6) Respond to their environment The maintenance of internal conditions is called homeostasis. e.g. sweating and shivering to maintain internal temperatures.  7) Evolve over time Evolution is the change in species over time. #3a) Prokaryotes and Eukaryotes Prokaryotic Cell (Prokaryote) -Kingdom Monera -small size (1 to 10 µm) -unicellular -lacks a nucleus -genetic material called nucleoid -lack membrane-bound organelles -cell wall present Eukaryotic Cell (Eukaryote) -Kingdoms Protista, Fungi, Plantae, and Animalia -large size (10 to 100 µm) -unicellular or multicellular -nucleus present -genetic material inside nucleus -many membrane-bound organelles -cell wall present in Plantae, Fungi, and some Protista Comparison of Prokaryotes and Eukaryotes Characteristics Prokaryote Eukaryote Kingdom(s) -Monera -Plantae, Fungi, Animalia, Protista Size -1 to 10 µm -10 to 100 µm Cell organization -unicellular -uni or multi Nucleus -absent -present Genetic material -nucleoid -chromosomes Organelles -mainly ribosomes -many Cell wall -present -Plantae, Fungi, and some Protista #3b) Organelles and Cell Structures  Eukaryotic Cell (Animal) centrioles golgi nucleolus cell membrane nuclear envelope chromatin mitochondria smooth ER cytoplasm microfilament nucleus rough ER ribosome lysosome microtubule nuclear pore vacuole  Cell Membrane Cell membrane – protective barrier of the cell; regulates what enters and exits the cell  Cytoplasm Cytoplasm – gel-like material; region between the cell membrane and the nucleus Nucleus, Nuclear Envelope, Nuclear Pore, Nucleolus, Chromatin Nucleus – controls cellular activities Nuclear envelope – outer boundary of the nucleus Nuclear pores – small openings found throughout the nuclear envelope Nucleolus – region of the nucleus where ribosomes are made Chromatin – DNA and protein mixture  Chromosomes Chromosomes – genetic information of the cell; made of chromatin (DNA and protein)  Ribosomes Ribosomes – small structures on which proteins are produced  Smooth and Rough ER Smooth Endoplasmic Reticulum – network of membranes used to transport materials Rough Endoplasmic Reticulum – similar to smooth ER but covered with ribosomes  Golgi Golgi – flattened structures that collect, modify, package, and transport materials  Lysosome Lysosome – contains chemicals and enzymes used to breakdown and recycle materials  Vacuole Vacuole – stores materials such as water, salts, proteins, and carbohydrates animal plant  Mitochondria Mitochondria – energy producing structures  Centrioles Centrioles – paired structures involved in cell division; organize spindle fibers  Microtubules and Microfilaments Microtubules – form the Microfilaments – form the cytoskeleton, cilia & flagella, cytoskeleton and centrioles & spindle fibers  Chloroplast (plants only) Chloroplast – location of photosynthesis  Cell Wall (plants) Cell Wall – thick outer layer; made of cellulose in plants  Prokaryotic Cell (Bacteria) A prokaryotic cell lacks a nucleus DNA (nucleoid)  Cell Wall (bacteria) Cell wall – outer protective layer; made of peptidoglycan in bacteria  Flagella Flagella – tail-like structure Pilus Flagella  Pilus Pilus (Pili) – structure used for conjugation, a form of sexual reproduction #4) Cell Types and Kingdoms  Kingdoms – Prokaryotic or Eukaryotic? Kingdoms: Prok. Or Euk.? Example (for SAS): 1) Monera -prokaryotic -cyanobacteria 2) Animalia -eukaryotic -liver cells, muscle cells, etc. 3) Plantae -eukaryotic -banana cells 4) Fungi -eukaryotic -yeast cells 5) Protista -eukaryotic -diatoms #5) Diffusion and Osmosis  Diffusion Diffusion is the movement of particles from an area of high concentration to low concentration. (potato cells stained with iodine)  Osmosis Osmosis is the movement of water across a semipermeable membrane toward a higher concentration of solute. hypertonic: high salt environment isotonic: outside salt = inside salt hypotonic: low/no salt environment  Plasmolysis of Onion Cells before Plasmolysis is when a plant cell loses water and the cell membrane pulls away from the cell wall occurs in a hypertonic environment after #6) Energy Production  Photosynthesis Photosynthesis – plants use chloroplasts to produce food in the form of glucose: 6CO2 + 6H2O + sunlight → C6H12O6 + 6O2  Cellular Respiration (Aerobic) Aerobic Cellular Respiration – cells produce energy by breaking down glucose: C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP(energy)  Cellular Respiration (Anaerobic) Anaerobic Cellular Respiration or Fermentation is the production of energy in the absence of oxygen. 1) Alcoholic fermentation: 2) Lactic acid fermentation: e.g. in yeast e.g. in muscle Examples of Fermentation #7) Reproduction in Cells  Types of reproduction in cells Asexual Sexual mitosis meiosis binary fission *conjugation budding spore formation  Mitosis Mitosis is asexual cell division; it maintains the number of chromosomes (e.g. in humans from 46 to 46). The result is two diploid daughter cells four stages: P-M-A-T Onion root-tip Onion Root-Tip Cell Division  The Cell Cycle Three stages of the cell cycle: 1) Interphase 2) Mitosis (P-M-A-T) 3) Cytokinesis Interphase The cell prepares for mitosis: G1 – Growth S – Synthesis of DNA G2 – Growth Prophase chromosomes condense nuclear membrane breaks down centrioles begin organizing spindle fibers Metaphase chromosomes align Anaphase sister chromatids separate Telophase chromosomes move to ends of cells spindle fibers disassemble nuclear membrane reforms Cytokinesis cytoplasm divides two diploid daughter cells result  Binary Fission Binary fission is a form of asexual reproduction in which the cell divides equally. e.g. Bacteria e.g. Amoeba  Budding Budding is a form of asexual reproduction in which the cell divides unequally. bud parental cell Budding yeast  Spore Formation Spores are reproductive cells that form by mitosis. e.g. Fungi e.g. Fern #8) Meiosis  Meiosis Meiosis is division of sex cells; it reduces the number of chromosomes in half (e.g. in humans from 46 to 23). The result is four haploid gametes (egg or sperm cells).  Conjugation Conjugation in bacteria is the transfer of DNA from cell to cell through a pilus It is not true sexual reproduction, but does increase genetic diversity