BIO 101 – Exam #2 Study Guide

1)Chromatin – strands of DNA in nucleus during Interphase

2)Sister chromatids = two half’s of a chromosome

3)Chromatids = 2x # of chromosomes /one half of a replicated chromosome

4)Chromosome = coiled up DNA that passes genes on the DNA to daughter cells when the cell divides

  1. most visible during mitosis/meiosis

5)Centromere – middle of a sister chromatid

  1. Divides at onset of Anaphase in Mitosis and Anaphase II in Meiosis

6)Spindle fibers – what pull chromosomes apart during cell division

7)Cleavage furrow – bit of cleavage that animal cells make when dividing

8)Diploid (2n) – cell containing 2 homologous sets of chromosomes, one from each parent

  1. Reproduces sexually
  2. What all cells have except egg + sperm
  3. Double the haploid

9)Haploid(n)– half the Diploid # of genes, is the egg + sperm cells

10)Dyad = 2 chromatid

11)Tetrad = 4 chromatid (Haploid #)

12)Crossing over – when chromosomes exchange segments to rearrange genetic information during Prophase I of Meiosis

13)Homologous chromosomes – 2 chromosomes making up matched pair in a diploid cell

  1. Same length, centromere position, and staining pattern
  2. Possess genes for same traits at corresponding loci
  3. 1 from father, 1 from mother

14) Autosomes – chromosome not involved in determining an organism’s sex

15)Sex chromosomes – determine organism’s sex

16)Gametes – reproductive cells (egg/sperm)

17)Chiasmata – microscopically visible site where crossing over has occurred between chromatids of homologous structures during Prophase I of Meiosis

18)Somatic cell – typical body cell

19)Karyotype – micrographs of the metaphase chromosomes of a cell (nucleus)

20)Karyokinesis – division of nucleus

21)Gametogenesis – creation of gametes within gonads

22)OOgenesis – creation of mature egg cells

23)Spermatogenesis – creation of sperm cells

24)Polar bodies – byproducts of primary/secondary oocyte at each point of meiotic division in oogenesis (not in spermatogenesis)

25)Girls are born with their eggs already made in Prophase I; puberty comes during Metaphase II

26)Prophase is longest phase of Meiosis

27)Klinefelters – XXY (when a male has an extra X chromosome)

28)Metafemale – XXX (when a female has an extra X chromosome)

29)Turners Syndrome – X0 (45 chromosomes in female, where they lack another X chromosome)

30)Not viable – Y0

31)Mitosis – growth/repair

  1. One diploid parent cell divides to form 2 genetically identical daughter cells
  2. Used for asexual reproduction in unicellular organisms
  3. Cell cycle = 90% Interphase, 10% Mitotic phase
  4. Interphase
  5. G1–cell grows + carries out normal metabolism; organelles duplicate
  6. S – DNA replication + chromosome duplication
  7. G2 – construction of spindle apparatus; chromosomes condense; cell continues growing
  8. Prophase – nuclear envelope + nucleoli disappear
  9. Spindle fibers begin to form
  10. Chromosomes begin to supercoil and are visible for 1st time
  11. Centrosome head to poles of cell
  12. Metaphase
  13. Spindle fibers fully formed
  14. Attached to all of the kinetochores
  15. Centrosome are on polar sides of cell
  16. Anaphase
  17. Sister chromatids pulled apart at centromere by spindle fibers retracting, resulting in 1 member of each sister chromatid pair moving into a new cell
  18. Telophase
  19. 2 daughter cells have clear body
  20. Spindle fibers start disappearing
  21. Nucleoli reappears
  22. Chromosomes uncoil
  23. Cytokinesis–division of the cell/cytoplasm to form 2 separate daughter cells
  24. Cleavage furrow forms

32)Meiosis – egg/sperm (sexual cell division)

  1. One parent cell(2n) divides to form 4 haploid daughter cells which are then processed into gametes
  2. Meiosis I – homologous chromosomes separate
  3. InterphaseI – chromosomes duplicates  each chromosome has 2 genetically identical sister chromatids
  4. Prophase I – crossing over occurs  tetrad forms as a result of synapsis
  5. Metaphase I – spindle microtubules attached to a kinetochore
  6. Anaphase I – sister chromatids remain attached  homologous chromosomes separate toward 2 poles of cell
  7. Telophase I + Cytokenesis – cleavage furrow forms
  8. Meiosis II – sister chromatids separate during Anaphase II

33)Chemistry/Periodic Table of Elements

  1. Proton = positive charge, Electron = negative charge, Neutron = neutral charge
  2. # of rows = # of rings of electrons an element has
  3. Atomic # = # of protons
  4. Atomic weight = weight of atom’s protons & neutrons
  5. 1st ring holds 2 electrons max
  6. 2nd ring holds 8 electrons max
  7. 3rd ring holds 18 electrons max
  8. 4th ring holds 32 electrons max
  9. Octet rule = outer ring of an atom holds 8 electrons or less
  10. Electrons are in electron cloud that surrounds nucleus of atom
  11. Protons & Neutrons are in the nucleus
  12. An atom is positively charged if it is missing 1 or more electrons, negatively charged if it has 1 or more electrons.
  13. Negatively atoms are attracted to positively charged atoms and vice versa
  14. Ions are a charged atom, positive or negative
  15. Isotopes are atoms with the same # of protons & electrons, but different # of neutrons.
  16. Ex. Carbon-12, carbon-13, and carbon-14 are 3 isotopes of Carbon with mass #’s 12, 13, and 14, respectively. Carbon’s atomic # is 6 meaning each carbon atom has 6 protons, thus they contain 6, 7, and 8 neutrons, respectively.
  17. ionic bond – chemical bond resulting from attraction between oppositely charged ions
  18. covalent bond – strong chemical bond where 2 or more atoms share one or more pairs of outer-shell electrons
  19. organic chemicals have carbon in covalent linkage
  20. hydrogen bond – hydrogen atoms holding molecules together

34)Cells

  1. Characteristics of life
  2. Nutrients
  3. Respiration
  4. Need energy
  5. Enzymes
  6. Cell structure
  7. Homeostasis
  8. Respond to stimuli, i.e. moisture/temp./taste
  9. Genetic material
  10. Reproduction
  11. Growth
  12. Waste
  13. Organelles
  14. Cytoskeleton – maintenance of cell shape; anchorage for organelles; movement of organelles within cells; cell movement; made up of microtubules, microfilaments, and intermediate filaments
  15. Flagella & cilia – used for movement; have a 9 + 2 arrangement of microtubules covered by cell’s plasma membrane
  16. Plasma membrane – consists of phospholipid bilayer with embedded proteins, at boundary of cell, acting as selective barrier to passage of ions/molecules in/out of cell
  17. Smooth ER – lipid synthesis; detox in liver cells; calcium ion storage
  18. Rough ER – synthesis of membrane lipids & proteins, secretory proteins, and hydrolytic enzymes; formation of transport vesicles
  19. Nucleus – DNA replication, RNA synthesis; assembling of ribosomal subunits
  20. Golgi body – organelle in eukaryotic cells consisting of membranous sacs that modify, store, and ship products of the ER
  21. Peroxisome – breaks down hydrogen peroxide
  22. Lysosomes – help digest food, bacteria, and a cell’s damaged organelles for recycling
  23. Mitochondria – conversion of food to energy (ATP)
  24. Chloroplasts – conversion of light energy to sugar (plant cells only)
  25. Ribosomes – protein synthesis
  26. Cell wall – support & protection; binding of cells in tissues (plant cells only)
  27. Centrioles – microtubules that are important for cell division in mitosis
  28. Chromatin – genetic material when a cell is not dividing
  29. Chromosome – genetic material when a cell is dividing
  30. Eukaryotic cell – cell that has a membrane-enclosed nucleus (plants/animals/fungi/Protista)
  31. Prokaryotic cell – cell lacking membrane-enclosed nucleus (bacteria/archaea = like extreme environments)
  32. Not in animal cells – central vacuole, chloroplast, cell wall, plasmodesmata
  33. Not in plant cells – lysosomes, centriole, flagellum
  34. Cytoplasm – contents of eukaryotic cell between plasma membrane & nuclear membrane
  35. Diffusion – going from area of high concentration to one of low concentration
  36. Osmosis – diffusion of water through a selectively permeable membrane
  37. Passive transport – diffusion of a substance across biological membrane w/o energy
  38. Active transport – movement of a substance across biological membrane against its concentration gradient aided by specific transport proteins and require energy (often as ATP)
  39. Facilitated diffusion – passage of a substance w/ help of specific transport protein across a biological membrane down its concentration gradient
  40. Phospholipid bilayer – phosphate head = hydrophilic/water-soluble; fatty acid = hydrophobic/water-insoluble
  41. Endocytosis – cellular uptake of molecules or particles via formation of new vesicles from plasma membrane
  42. Phagocytosis – type of endocytosis consisting of cell “eating”
  43. Pinocytosis – type of endocytosis consisting of cell “drinking”
  44. Exocytosis – movement of materials out of a cell’s cytoplasm by fusion of vesicles w/ plasma membrane
  45. Receptor-mediated endocytosis – movement of specific molecules into a cell by inward budding of membrane vesicles, containing proteins w/ receptor sites specific to molecules being taken in
  46. Isotonic – a solution when surrounding a cell that has no effect on passage of water in/out of the cell
  47. Hypertonic – more solute outside, water flows out, cell shrinks (crenation)
  48. Hypotonic – more solute inside, water flows in, cell bursts (lysis)
  49. Word roots
  50. Cyto = cell
  51. Lyso = breakdown
  52. Some = body
  53. Endo = inside
  54. Exo = outside
  55. Pro = before
  56. Eu = real/true
  57. Kary = nucleus
  58. Chrome = color
  59. Lipo = fat
  60. Hyper = too much
  61. Hypo = too little

35)Scientific Method

  1. Observations
  2. Hypotheses
  3. Predictions
  4. Experimentation
  5. Conclusions

36)Metric System

  1. Used to measure length, weight, volume, and temperature
  2. Length
  3. 1,000m = 1km
  4. 1.6km = 1 mile
  5. Kilo = 1,000
  6. 1m = 100 centi (hundredth) = 1,000 milli (thousandth) = 1,000,000 micro (millionth) = 1,000,000,000 nano (billionth) = 10,000,000,000 angstrom (ten billionth)
  7. 5,280 ft = 1 mile
  8. 30cm = 1ft
  9. 2.54cm = 1in
  10. Weight
  11. ST (short ton) = 2,000lbs (used in U.S.)
  12. Long Ton = 2,240lbs (used in ships)
  13. Metric Ton = 1,000kg = 2,206lbs
  14. Volume
  15. 1 barrel of oil = 42 gallons
  16. 1 gallon = 3.78 liters
  17. 1 liter = 1.06 quarts
  18. Temperature
  19. 0 degrees C = 32 degrees F
  20. 100 degrees C = 212 degrees F
  21. 37 degrees C = 98.6 degrees F
  22. 20 degrees C = 68 degrees F

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