Which of the following hypotheses relies on the chemical reaction between hydrogen sulfide (HS2) and iron (Fe) for the built up of a H2 concentration gradient to provide the necessary energy for the reduction of N2 to NH3?
A. Reducing Atmosphere Hypothesis.
B. Extraterrestrial Hypothesis.
C. Deep-Sea Vent Hypothesis.
D. Both Reducing Atmosphere and Extraterrestrial Hypotheses.
E. All three hypotheses use this exact reaction to create a chemical gradient to form amino acids.
C. Deep-Sea Vent Hypothesis.
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Answer the following statements true (T) or false (F)
1. When a molecule of NAD+ gains a hydrogen atom, the molecule becomes reduced. 2. Proteins and fats may be used as energy sources to drive aerobic respiration. 3. During the energy investment phase of glycolysis, glucose has a decrease in free energy. 4. The rate of photosynthesis is much greater in green light than red light.
Which two structures will help the plant conserve water during times of drought?
a. Stomata and porous roots b. Stomata and cuticle c. Cuticle and broad surface area on the leaves d. Cuticle and porous roots e. Stomata and porous epidermis
Botulinum toxin has been used for all of the following purposes except
a. for cosmetic purposes, to treat “dynamic wrinkles.” b. to treat facial and eyelid spasms. c. for OCD and autism. d. to treat dystonias, prolonged muscle contractions. e. for certain types of cerebral palsy.
Tightly curled hair is caused by a dominant autosomal gene in humans. If a heterozygous curly-haired person marries a person with straight hair, what phenotypes (and in what proportions) are expected in the offspring?
What will be an ideal response?