Midterm Study guide

  1. What are the products of photosynthesis?
    oxygen & sugar
  2. What happens during photosynthesis?
    • plants and some other organisms use energy from the sun to convert
    • carbon dioxide & water into oxygen & sugar
  3. How does photosynthesis benefit heterotrophs?
    makes food for them to eat
  4. What happens during respiration?
    • cells break down simple food molecules such as sugar and glucose
    • and release the energy they contain
  5. The stage of respiration that releases most of the energy in glucose
    occurs in the
  6. How are photosynthesis and respiration related?
    same formulas just opposite
  7. Together, respiration and photosynthesis keep the levels of carbon
    dioxide and oxygen in the atmosphere
    a.fairly constant.
    b.constantly changing.
    c.constantly increasing.
    d.constantly decreasing.
  8. The energy-releasing process that does not require oxygen is
  9. When is lactic-acid fermentation most likely to occur?
    running fast or exercising
  10. Explain the process of Mitosis. Know all stages and what occurs in
    each stage.
    • Prophase – Chromatin in the nucleus condenses to form chromosomes. The parts of centrioles move to opposite
    • sides of the nucleus. Spindle fibers form a bridge between the ends of the
    • cell.

    • Metaphase – The chromosome line up across the center of the cell. Each chromosome
    • attaches to a spindle fiber at its centromere.

    • Anaphase – The centromeres split. The 2 chromatids separate. One chromatid is drawn by
    • its spindle fiber to one end of the cell. The other chromatid moves to the
    • opposite end. The cell stretches out as the opposite ends are pushed apart.

    • Telophase – The chromosomes begin to stretch out and lose their rodlike appearance. A new
    • nuclear envelope forms around each region of chromosomes.

    cell’s nucleus divides into 2 new nucleus – remember cell cycle (the word)
  11. What happens during cytokinesis in animal cells?
    • the cell membrane squeezes together around the middle of the cell. The
    • cytoplasm pinches into 2 cells. Each daughter cell gets about half of
    • the organelles
  12. Explain the DNA molecule. What shape is it? What are the nitrogen
    base pairs and how do they pair up with each other?
    twisted ladder or spiral stair case. Adenine(A)-Thymine(T) Cytosine(C)-Guanine(G)
  13. What captures energy from sunlight during photosynthesis?
    stomata-Co2 collector Chloraphyll-pigments
  14. Where does alcoholic fermentation occur?
    yeast – single celled organisms
  15. What are chromatids?
    each identical rod in a chromosome – identical strands of chromosomes
  16. What forms around the chromatids during mitosis?
    2 new nuclei form around the chromatid
  17. All organic compounds contain the element
  18. Why is water important for a cell?
    water helps keep their size and shape. It helps keep the temperature from changing rapidly
  19. Active transport
    the movement of materials through a cell membrane using energy
  20. Diffusion
    • the process by which molecules move from an area of higher concentration
    • to an area of lower concentration
  21. Engulfing
  22. Passive transport
    the movement of dissolved materials through a cell membrane without using cellular energy
  23. Why are enzymes important?
    without enzymes, many chemical reactions that are necessary for life would either take too long or not occur at all
  24. What are startches? Lipids?
    • 1. carbohydrate; many foods made of plants contain this
    • 2. energy-rich organic compounds made of carbon, hydrogen, and oxygen
  25. Define compound.
    when 2 or more elements combine chemically
  26. What did Gregor Mendel do to study different characteristics in his
    genetics experiments?
    • crossed pea plants – crossed purebred tall pea plants with purebred
    • short pea plants
  27. Explain Mendel’s experiment in detail. P generation, F1 Generation, F2 generation.
    • 1. parent generation. He crossed T with t T-tall t-short
    • 2. the offspring form the T and t cross. All the offsprings were tall. TT
    • 3. the plants were a mix of tall and short. the shortness trait has reappeared. ¾ of
    • the plants were tall and ¼ were short. TTTt
  28. Genes
    the factors that control a trait
  29. Purebreds
    offspring of many generations that have been the same trait
  30. Recessives
    an allele that is hidden when the dominant allele is present
  31. Trait
    each different form of a characteristic
  32. hybrid
    2 different alleles for a trait
  33. probability
    a # that describes how likely it is that an event will occur
  34. punnett square
    • a chart that shows all the possible combinations of alleles that can
    • result from a genetic cross
  35. genotype
    genetic makeup, allele combinations
  36. phenotype
    physical appearance, visible traits
  37. codominance
    • a condition in which neither of 2 alleles of a gene is dominant or
    • recessive
  38. heterozygous
  39. mutation
    a change in a gene or chromosome
  40. allele
    different form of a gene
  41. homozygous
    TT or tt
  42. What does the notation TT, Tt, tt, mean to geneticists?
    • TT – dominant homo Tt – dominant
    • hetero tt – recessive homo
  43. What is the probability of producing a tall pea plant from a
    genetic cross between two hybrid tall pea plants?
    ¾ or 75%
  44. If a homozygous black guinea pig (BB) is crossed with a
    homozygous white guinea pig (bb), what is the probability that an
    offspring will have black fur?
  45. What is the chromosome theory of inheritance?
    genes are carried from parents to offspring on chromosomes
  46. What did Walter Sutton do?
    • discover Theory of Inheritance. grasshoppers – sex cells, half the
    • # of chromosomes in body cells
Card Set
Midterm Study guide
Science Midterm Study Guide