Molecules tend to move across the plasma membrane
A) both up and down their concentration gradients equally
B) in unpredictable directions
C) up their concentration gradients
D) down their concentration gradients
Answer: D
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The Cellular Level of Organization
- Lysosomes help destroy worn-out organelles by the process of (blank).
- Cells have the ability to divide an unlimited number of times.
- Which of the following choices shows the correct order of cell diameters, from smallest to largest?
- The enzymes that splice the introns out of the initial mRNA strands are (blank).
- Which of the following would be found in the nucleus?
- The backbone of a phospholipid molecule is a (blank) molecule, which is attached to two hydrophobic tails and a phosphate head group.
- Carrier proteins are also known as (blank) and can move polar molecules, like glucose, across the plasma membrane.
- The (blank) that are produced at the end of meiosis are genetically unique; they are not the same as the parent cell or identical to each other.
- Identification and discovery of new genes is the focus of (blank) research.
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- If a codon on an mRNA molecule is ACG, the anticodon that binds to it will be
- Pancreatitis is an acute inflammation of the pancreas, caused by the premature activation of digestive enzymes that then digest the pancreatic tissue and cause severe homeostatic imbalances. These enzymes are often found in which part of the cell?
- The medical branch that deals with treating the elderly and their associated medical problems is known as (blank).
- Your patient has a benign tumor in her head and is complaining of headaches of increasing severity. You find that the humor has grown in recent months. Which of the following could be occurring in this tumor?
- Sodium ions (Na+) move across the plasma membrane (blank).
- Cells that contain long extensions and conduct electrical impulses are the (blank).
- A nucleosome is (blank).
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- Patients may be treated for cancer through a variety of methods. Which of the following may be used for treating a cancer patient?
- Components of the cytoskeleton include which of the following?
- Translation occurs in the (blank).
- Transporters are a type of integral protein also known as a(n) (blank).
- Chickens are eukaryotic and sexually-reproducing, much like humans. If a chicken skin cell has 78 chromosomes, how many chromosomes would an unfertilized chicken egg contain?
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- Cancers are most often named based on the region of the body in which they form; therefore, you would expect the (blank) to be the origin of a tumor whose name includes neuro.