If you add a compound to illuminated chloroplasts that inhibits the NADP+ reductase, NADPH generation ceases, as expected
However, ferredoxin does not accumulate in the reduced form because it is able to donate its electrons not only to NADP+ (via NADP+ reductase) but also back to the cytochrome b6-f complex. Thus, in the presence of the compound, a "cyclic" form of photosynthesis occurs in which electrons flow in a circle from ferredoxin, to the cytochrome b6-f complex, to plastocyanin, to photosystem I, to ferredoxin. What will happen if you now also inhibit photosystem II?
(a) Less ATP will be generated per photon absorbed.
(b) ATP synthesis will cease.
(c) Plastoquinone will accumulate in the oxidized form.
(d) Plastocyanin will accumulate in the oxidized form.
(c) If you now inhibit photosystem II, you will deprive plastoquinone, which can still donate its electrons to the cytochrome b6-f complex, of an electron source. Hence, plastoquinone will accumulate in its oxidized form. In contrast, all of the other components downstream of plastoquinone will be able to cycle between their oxidized and reduced states. ATP synthesis will continue, because electrons are still being fed through the cytochrome b6-f complex, and the same amount of ATP will be generated.
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As the result of exposure to a mutagen, cytosine is substituted for thymine in one strand of DNA. Upon subsequent DNA replication, one of the daughter cells will have a GC pair in this position instead of an AT pair. This is called a(n) ________ mutation.
A. insertion B. transition C. frameshift D. transversion
Exhalation
a. is always active. b. is always passive. c. may be both active and passive. d. compresses alveoli. e. may be both active and passive, and compresses alveoli
Which of the following is true concerning postnatal development?
a. Infancy is defined as the first two years of life after birth. b. Senescence results in increased hormone secretion. c. Postnatal development occurs before birth. d. In general, boys experience their pre-adolescent growth spurt later than girls. e. Early childhood is a time of rapid cell division in nerve cells.
Answer the following questions true (T) or false (F)
1. Roseola is a rare but very dangerous childhood viral infection. 2. Pityriasis' characteristic appearance is the result of a fungal infection causing changes in the production of melanin. 3. Cryptococcal meningitis can affect both healthy and immunocompromised individuals.