Biology 2 exam

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Biology 2 exam
2013-03-13 17:55:54
exam biology ch4

ch4-7 biology exam2
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  1. What is the cell theory
    The idea that all organisms are composed of cells
  2. What are the 3 principle sof the cell theory
    • 1. All organisms are composed of one or more cells with which the process of life occur.
    • 2.)Cell are the smallest living things
    • 3.) Cells arise only by division of previously existing cells
  3. Why are most cells small
    Because larger cells do not function as effeciently
  4. The only way to increase resolution is to
    increase magification
  5. What are the different types of microscopes
    compund microscope, transmission electron microscope, and the scanning electron microscope.
  6. What is the prokaryotic cell composed of
    cytoplasm, ribosomes, DNA, nucleiod region, plasma membrane, cell wall, capsule.
  7. A normal eukaryotic cell has
    cytoskeleton, centriole, cytoplasm, mitochondira, secretory vesicle, lysome, golgi complex, peroxisome, nucleus, smooth and rough ER,
  8. What do only plant cells have?
    Chloroplast, cell walls, plasmodesmata, central vacuole.
  9. Why does a lipid bilayer occur spontaneously?
    A phospholipid has two ends: one is "comfortable" in water; the other is not. The result is that any phospholipids, even in a glass of water, will bring their "water-avoiding" ends together, and leave the "water-liking" ends on the outside. In short, phospholipids in the presence of water form a bilayer. 
  10. What do membrane proteins do?
    they project up from the surface and act as a beacon to bind specific hormones or proteins to the cell.
  11. what are transmembrane proteins?
    They extend all the way through the bilayer and provide passage ways for ions and polar molecules like water
  12. What 2 things does the nucleus do?
    It acts as a command center and it also is the genetic library where hereditary info is stored.
  13. Why is it called the rough ER?
    Because it is studded with ribosomes.
  14. What do plant vacuoles act as?
    A storage center for ions, water, sugar, and pigments.
  15. What is the difference between mitochondria and chloroplast?
    Chloroplast is more complex and larger it also has thylakoids.
  16. How do we know mitochondia is related to bacterium?
    Because mitochondrial DNA closely resembles the circular DNA of bacterium. And both replicate their DNA during division.
  17. How do animal cells move?
    Using cilia or flagella
  18. What is diffusion?
    the net movement of molecules to regions of lower concentration as a result of random molecular motions
  19. Osmosis
    water passes across a cell membrane down its concentration gradient
  20. Organisms maintain osmotic balance in three ways...
    • 1. Extrusion
    • 2. Isosmotic regulation
    • 3. turgor
  21. what is selective diffusion?
    controls what enters and exits the membrance by using proteins
  22. what is facilitated diffusion?
    passive transport, allows substances to cross membrane with the assistance of special transport proteins
  23. phagocytosis
    cells engulf organisms or fragments of organisms
  24. Pinocytosis
    material brought into the cell is liquid containing dissolved molecules
  25. Protein fibers of the cytoskeleton are made of
    Microfilaments and microtubules
  26. fluid mosaic model
    biological membranes can be considered as a two-dimensional liquid in which lipid and protein molecules diffuse more or less easily.
  27. Organelle
    They are membrane-bound compartments or structures of a cell that preform specific functions.
  28. exocytosis
    The process in which the cell releases materials to the outside by discharging them asmembrane-bounded vesicles passing through the cell membrane
  29. endocytosis
    A process in which cell takes in materials from the outside by engulfing and fusing them with its plasma membrane.
  30. Calvin cycle
    The Calvin cycle is a process that plants and algae use to turn carbon dioxide from the air intosugar, the food autotrophs need to grow.
  31. calvin cycles four main steps
    • 1. carbon fixation 
    • 2.reduction phase
    • 3. carbohydrate formation
    • 4. regeneration phase.
    • Energy to fuel chemical reactions in this sugar-generating process is provided by ATP and NADPH, chemical compounds which contain the energy plants have captured from sunlight.
  32. Energy
    The capacity for work or vigorous activity
  33. Kinetic energy
    Energy a body has because it is in motion
  34. Potential energy
    Energy that is stored. To be used, potential energy must be converted into one of the six forms of kinetic energy.
  35. The first law of thermodynamics
    Heat and work are forms of energy transfer. Energy is invariably conserved however the internal energy of a closed system may change as heat is transferred into or out of the system or work is done on or by the system. In real systems work does not alwaysleave the system. For example, changes in molecular energy (potential energy), are generally considered to remain within the system. Similarly, the rotational and vibrational energies of polyatomic molecules remain within the system.
  36. difference between endergonic and exergonic reactions
    • is a chemical reaction in which the standard change in free energyis positive, and energy is absorbed. In layman's terms the total amount of energy is a loss (it takes more energy to start the reaction than what you get out of it) so the total energy is a negative net result.
    •  Exergonic reactions are those in which the free energy of the final state is less than the free energy of the initial state.This represents energy that can be used to do biological work
  37. Entropy
    Entropy is a mathematically-defined thermodynamic quantity that helps to account for the flow of energy through a thermodynamic process
  38. activation energy
    The least amount of energy needed for a chemical reaction to take place.
  39. cataylsis
    acceleration of a chemical reaction by the action of a catalyst
  40. ATP
    Adenosine triphosphate (ATP) is considered by biologists to be the energy currency of life. It is the high-energy molecule that stores the energy we need to do just about everything we do. It is present in the cytoplasm and nucleoplasm of every cell, and essentially all the physiological mechanisms that require energy for operation obtain it directly from the stored ATP. (Guyton) As food in the cells is gradually oxidized, the released energy is used to re-form the ATP so that the cell always maintains a supply of this essential molecule. Karp quotes an estimate that more than 2 x 1026 molecules or >160kg of ATP is formed in the human body daily! ATP is remarkable for its ability to enter into many coupled reactions, both those to food to extract energy and with the reactions in other physiological processes to provide energy to them. In animal systems, the ATP is synthesized in the tiny energy factories called mitochondria.
  41. ATP to ADP
    The ATP can power needed reactions by losing one of its phosphorous groups to form ADP, but you can use food energy in the mitochondria to convert the ADP back to ATP so that the energy is again available to do needed work.
  42. photosynthesis
    Photosynthesis is the process of converting light energy to chemical energy and storing it in the bonds of sugar.This process occurs in plants and some algae
  43. The 3 layers of leaf that light must pass through to reach the chloroplast
    • 1. Cuticle
    • 2. epidermis
    • 3.) Mesophyll cells