The early suggestion that the oxygen (O2) liberated from plants during photosynthesis comes from water was
A) first proposed by C.B. van Niel of Stanford University.
B) confirmed by experiments using oxygen-18 (18O).
C) made following the discovery of photorespiration because of rubisco's sensitivity to oxygen.
D) A and B
E) A, B, and C
Answer: B
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AP Biology Practice Questions
- You have in your possession a microscope slide with meiotic cells on it and a light microscope. What would you look for if you wanted to identify metaphase I cells on the slide?
- The process is preceded by replication of the DNA.
- Independent assortment of chromosomes occurs
- Centromeres uncouple and chromatids are separated from each other.
- A cell divides to produce two daughter cells that are genetically identical.
- Which of the following is true of the process of meiosis?
- Which of the following happens at the conclusion of meiosis I?
- Centromeres of sister chromatids uncouple and chromatids separate.
- Synapsis of homologous pairs occurs; crossing over may occur.
- Which of the following terms belongs with the words synapsis, tetrads, and chiasmata?
- How do cells at the completion of meiosis compare with cells that have replicated their DNA and are just about to begin meiosis?
- After telophase I of meiosis, the chromosomal makeup of each daughter cell is
- Which of these statements is false?
- In animals, meiosis results in gametes, and fertilization results in
- Eukaryotic sexual life cycles show tremendous variation. Of the following elements, which do all sexual life cycles have in common?
- Which of the following is the term for a human cell that contains 22 pairs of autosomes and two X chromosomes?
- The human X and Y chromosomes are
- How do the two members of a pair of homologous chromosomes differ from each other?
- Which of the following statements about genes is incorrect?
- What is a genome?
- Which of the following is (are) true concerning cyclin-dependent kinase (Cdk)?
- Which of the following is true concerning cancer cells?
- Nerve and muscle cells are in this phase
- The "restriction point" occurs here.
- Triggers the cell's passage past the G2 checkpoint into mitosis