ASU BIO 181 Exam 1 Newest 2025 Complete 100 Questions

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ASU BIO 181 Exam 1 Newest 2025 Complete 100 Questions And Correct Answers (Verified Answers) |Already Graded A+

The plasma membrane gets new lipids from:

A.The lumen of the ER.

• The lumen of the Golgi apparatus.
• Making new lipids at the plasma membrane.
• The nucleus.
• None of the above. - ANSWER-E. None of the above

What is the difference between a single-pass transmembrane protein and a 7-pass transmembrane protein? - ANSWER-Because the inside of the phospholipid bilayer of the cell membrane is hydrophobic, this one hydrophobic peak indicates the glycophorin only cross the phospholipid bilayer once, and thus a single pass protein. Multi pass proteins cross the plasma membrane multiple times.

A single pass trans-membrane protein that is an alpha helix can make a channel. - ANSWER-FALSE

Cholesterol is _____ to have in biological membranes. - ANSWER- Good

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Explain the evolutionary origin of the endoplasmic reticulum, Golgi apparatus and vesicles. - ANSWER-The endoplasmic reticulum (ER) plays a key role in the modification of proteins and the synthesis of lipids.The Endoplasmic reticulum, Golgi, and vesicles all evolved from the endomembrane system which is when the cells surface became flexible many millions of years ago due to losing the cell wall. This allowed for the exchanging of material with the environment to happen rapidly, which then lead to the cell to sustain a larger volume and have a more rapid metabolism.

The ER is contiguous with the nuclear envelope. - ANSWER-TRUE

Facilitated diffusion uses a channel protein to let components move down their concentration gradient. - ANSWER-TRUE

Explain how the vesicles are carried from the Golgi apparatus to the plasma membrane. - ANSWER-The vesicles are carried from the Golgi to the plasma membrane by the microtuble system (which doesn't reach all the way to the plasma membrane) so then it later goes to the actin filament system (which are connected to plasma membrane)

For a protein to enter the endoplasmic reticulum as part of the endoplasmic reticulum's lumen or part of the endoplasmic reticulum's

membrane:

• The messenger RNA goes directly to the ER. 2 / 3

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• A ribosome binds to the mRNA and a short stretch of protein is

synthesized that contains a signal sequence.

• Ribosomes at the endoplasmic reticulum bind to the protein
• Is a random event and one day the protein could go to the ER and on

another day the same protein could associate with a free polyribosome.

• None of the above. - ANSWER-B. A ribosome binds to the mRNA

and a short stretch of protein is synthesized that contains a signal sequence.

Explain the evolutionary origin of mitochondria. - ANSWER-Anaerobic eukaryote engulfed an aerobic alpha-proteobacterium which then became an endosymbiont providing ATP from respiration while receiving substrates and protection

It is a simple matter (i.e., thermodynamically favorable) for a vesicle to form from the endoplasmic reticulum. - ANSWER-FALSE

Amino acids can be largely subdivided into two groups. What are the two groups? - ANSWER-Hydrophilic and Hydrophobic.

The ER is contiguous with the Golgi apparatus. - ANSWER-FALSE

What is the difference between a triglyceride and a phospholipid? - ANSWER-Triglycerides have three fatty acids attached to the glycerol

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