Biology 151 Exam A+ Pass Verified New
Update
Which of the following statements are true regarding plasma membranes and
phospholipids?
I. All animal and plant cells, but not bacterial cells, have plasma membranes.
II. Saturated fatty acids contain no double bonds.
III. The hydrophilic head groups of phospholipids are found in the interior of the lipid
bilayer.
IV. Phospholipids are amphipathic. - Answer ✔✔- II and IV
The skin cells have high concentrations of cholesterol (in the plasma membranes).
What does this mean for the fluidity of those cells compared to cells with low cholesterol
concentrations? - Answer ✔✔- At high temperatures, these skin cells are less fluid than
cells with less cholesterol.
The heart pumps blood around the body. Calcium ions (Ca2+) play an important role in
the electrical activity and pumping function of the heart. When voltage-gated calcium ion
channels open in heart muscle cells, Ca2+ ions rush into the cytoplasm. This is an
example of: - Answer ✔✔- Facilitated diffusion
Which parts of this system are primary active transport and which are secondary active
transport; the Na+/Ca2+ exchanger pump and the sodium-potassium pump (Na+/K+)? -
Answer ✔✔- The Na+/K pump is primary active transport and the Na+/Ca2+ exchanger
is secondary active transport.
. Which of the following correctly describes what happens in the Na+/Ca2+ exchanger?
- Answer ✔✔- Na+ moves down its concentration gradient and Ca2+ moves up.
You're studying the HSC gene, which is expressed only in hematopoietic cells.
Hematopoietic cells are adult stem cells that give rise to other blood cells. You want to
obtain samples of the HSC gene for your BIO 151 Exam 1 Zehnder Fall 2021 5
experiments. You have access to white blood cells (differentiated blood cells),
embryonic stem cells, and hematopoietic cells. From which cells could you obtain the
HSC gene? - Answer ✔✔- From hematopoietic cells, embryonic stem cells, and white
blood cells.
Which of the following statements are true regarding stem cellsI. Stem cells are found in
embryos and are not present in adult tissues or organs.
II. Stem cells divide and differentiate to replace old cells or cells lost to injury or disease.
III. Totipotent stem cells contain more DNA than multipotent stem cells. - Answer ✔✔- II
only
, What is the immediate next step after TK2 is phosphorylated by TK1? - Answer ✔✔-
TK2 phosphorylates the transcription factor
Which of the following modifications to the signaling pathway would lead to a functional,
but temporary, pathway? You can assume protein turnover occurs and the signal is
present. - Answer ✔✔- TFa activates gene expression and targets TK2 for ubiquitin-
dependent proteolysis.
. Which of the following statements about this molecule are true?
I. This molecule is cholesterol.
II. Region A is polar and region B region is nonpolar.
III. Region C is a saturated fatty acid. - Answer ✔✔- II and III
You grow Tetrahymena in normal temperatures and then expose these Tetrahymena to
cold temperatures. Which of the following changes in plasma membrane composition
are likely to occur?
I. An increase in the concentration of unsaturated fatty acids.
II. A decrease in the length of the fatty acid tails.
III. A decrease in the concentration of unsaturated fatty acid tails.
IV. An increase in the length of the fatty acid tails. - Answer ✔✔- I and II
Which of the following statements about the sodium-potassium pump are true?
I. The sodium-potassium pump moves sodium ions (K+) from an area of high K+
concentration to an area of low K+ concentration.
II. The sodium potassium pump is a form of secondary active transport.
III. The sodium-potassium pump requires ATP. - Answer ✔✔- III only
Sodium-glucose transporters are a family of glucose transporter found in the intestinal
mucosa of the small intestine and the proximal tubule of the nephron. These Na-glucose
transporters are powered by the Na-K pump. Which of the following correctly describes
what happens in the Na-glucose transporter? - Answer ✔✔- Na+ moves down its
concentration gradient and glucose moves up.
Which of the following statements about this pathway is/are true?
I. SK2 is a phosphatase.
II. Expression of protein 2 after the signal is received is an example of a positive
feedback loop.
III. After the growth factor binds to the receptor, protein 1 will be expressed. - Answer
✔✔- III only
. You have a sample of cells that have not been exposed to the growth factor. Which of
the following would you expect to see when you measure these cells? - Answer ✔✔-
TFA is inactive and in the cytoplasm.
Update
Which of the following statements are true regarding plasma membranes and
phospholipids?
I. All animal and plant cells, but not bacterial cells, have plasma membranes.
II. Saturated fatty acids contain no double bonds.
III. The hydrophilic head groups of phospholipids are found in the interior of the lipid
bilayer.
IV. Phospholipids are amphipathic. - Answer ✔✔- II and IV
The skin cells have high concentrations of cholesterol (in the plasma membranes).
What does this mean for the fluidity of those cells compared to cells with low cholesterol
concentrations? - Answer ✔✔- At high temperatures, these skin cells are less fluid than
cells with less cholesterol.
The heart pumps blood around the body. Calcium ions (Ca2+) play an important role in
the electrical activity and pumping function of the heart. When voltage-gated calcium ion
channels open in heart muscle cells, Ca2+ ions rush into the cytoplasm. This is an
example of: - Answer ✔✔- Facilitated diffusion
Which parts of this system are primary active transport and which are secondary active
transport; the Na+/Ca2+ exchanger pump and the sodium-potassium pump (Na+/K+)? -
Answer ✔✔- The Na+/K pump is primary active transport and the Na+/Ca2+ exchanger
is secondary active transport.
. Which of the following correctly describes what happens in the Na+/Ca2+ exchanger?
- Answer ✔✔- Na+ moves down its concentration gradient and Ca2+ moves up.
You're studying the HSC gene, which is expressed only in hematopoietic cells.
Hematopoietic cells are adult stem cells that give rise to other blood cells. You want to
obtain samples of the HSC gene for your BIO 151 Exam 1 Zehnder Fall 2021 5
experiments. You have access to white blood cells (differentiated blood cells),
embryonic stem cells, and hematopoietic cells. From which cells could you obtain the
HSC gene? - Answer ✔✔- From hematopoietic cells, embryonic stem cells, and white
blood cells.
Which of the following statements are true regarding stem cellsI. Stem cells are found in
embryos and are not present in adult tissues or organs.
II. Stem cells divide and differentiate to replace old cells or cells lost to injury or disease.
III. Totipotent stem cells contain more DNA than multipotent stem cells. - Answer ✔✔- II
only
, What is the immediate next step after TK2 is phosphorylated by TK1? - Answer ✔✔-
TK2 phosphorylates the transcription factor
Which of the following modifications to the signaling pathway would lead to a functional,
but temporary, pathway? You can assume protein turnover occurs and the signal is
present. - Answer ✔✔- TFa activates gene expression and targets TK2 for ubiquitin-
dependent proteolysis.
. Which of the following statements about this molecule are true?
I. This molecule is cholesterol.
II. Region A is polar and region B region is nonpolar.
III. Region C is a saturated fatty acid. - Answer ✔✔- II and III
You grow Tetrahymena in normal temperatures and then expose these Tetrahymena to
cold temperatures. Which of the following changes in plasma membrane composition
are likely to occur?
I. An increase in the concentration of unsaturated fatty acids.
II. A decrease in the length of the fatty acid tails.
III. A decrease in the concentration of unsaturated fatty acid tails.
IV. An increase in the length of the fatty acid tails. - Answer ✔✔- I and II
Which of the following statements about the sodium-potassium pump are true?
I. The sodium-potassium pump moves sodium ions (K+) from an area of high K+
concentration to an area of low K+ concentration.
II. The sodium potassium pump is a form of secondary active transport.
III. The sodium-potassium pump requires ATP. - Answer ✔✔- III only
Sodium-glucose transporters are a family of glucose transporter found in the intestinal
mucosa of the small intestine and the proximal tubule of the nephron. These Na-glucose
transporters are powered by the Na-K pump. Which of the following correctly describes
what happens in the Na-glucose transporter? - Answer ✔✔- Na+ moves down its
concentration gradient and glucose moves up.
Which of the following statements about this pathway is/are true?
I. SK2 is a phosphatase.
II. Expression of protein 2 after the signal is received is an example of a positive
feedback loop.
III. After the growth factor binds to the receptor, protein 1 will be expressed. - Answer
✔✔- III only
. You have a sample of cells that have not been exposed to the growth factor. Which of
the following would you expect to see when you measure these cells? - Answer ✔✔-
TFA is inactive and in the cytoplasm.
