You are a scientist observing a membrane through which water and some small hydrophobic molecules can freely pass along a concentration gradient from high to low. However, some sugar molecules are too large to pass through the membrane either way without the assistance of passive transport proteins. Additionally, small Na ions and some proteins can pass through the membrane against the concentration gradient, but both require the assistance of active transport proteins. What general type of membrane are you observing?
a. impermeable
b. impenetrable
c. semipermeable
d. completely permeable
Answer: c. semipermeable
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A student wants to clone a DNA sequence of ~200 kb in length. Which vector would be most appropriate?
A) a plasmid B) a bacteriophage C) a bacterial artificial chromosome (BAC) D) a plant virus E) a large polypeptide
The field of ____________________ investigates similarities and differences in the genomes from different species
Fill in the blank(s) with correct word
Select the statement that is TRUE during expiration?
a. Transpulmonary pressure (Ptp)= 0 b. Alveoli pressure (Palv)? atmospheric pressure (Patm)= 0, and Palv = Patm c. Palv is greater than Patm, Palv ? Patm is positive and airflow is outward d. Intrapleural pressure (Pip) becomes more negative
The conversion of amino acids to carbohydrates is an example of
A) amination. B) gluconeogenesis. C) substrate-level phosphorylation. D) beta-oxidation. E) electron transport.