Which of the following were instrumental in DISPROVING spontaneous generation?
a. Pasteur's experiments using a specialized swan-necked flask that prevented microbes from entering flasks open to the air.
b. The theory set forth by Rudolph Virchow, stating that living cells arise only from preexisting cells.
c. Needham's experiments showing that even boiled vials of meat broth, when covered, became cloudy, teeming with microorganisms after a few days.
d. Spallanzani's experiment in which flasks of meat broth were boiled and then melted shut, preventing the passage of air altogether.
Answer: a. Pasteur's experiments using a specialized swan-necked flask that prevented microbes from entering flasks open to the air.
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Answer the following statements true (T) or false (F)
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An enzyme is what type of macromolecule?
a. carbohydrate b. protein c. lipid d. element
You are performing a Gram stain on gram-negative bacteria and you stop after the decolorizer step. What is the appearance of the bacteria at this point?
A) purple B) red C) colorless D) brown
During which phase do sister chromatids separate?
metaphase interphase anaphase prophase telophase