Plant seeds contain storage proteins that are encoded by plant genes. When the seed germinates, these proteins are rapidly hydrolyzed (i.e., the covalent bonds between amino acids within the polypeptides are broken), which releases amino acids for the developing seedling. Would you expect the genes that encode plant storage proteins to evolve slowly or rapidly compared with genes that encode enzymes? Explain your answer.

Reconsider the above problem. Using appropriate software, study the effects of both air and helium flowing steadily in a nozzle when there is a normal shock at a Mach number in the range $2<\mathrm{Ma}_1<3.5$. In addition to the required information, find the entropy change of the air and helium across the normal shock. Tabulate the results in a parametric table.

Complementary proteins provide all twenty essential amino acids. True or false.

A normal shock occurs when a pitot-static tube is inserted into a supersonic wind tunnel. Pressures measured by the tube are $p_{0_2}=10 \mathrm{psia}$ and $p_2=8 \mathrm{psia}$. Before the shock, $T_1=285^{\circ} \mathrm{R}$ and $p_1=1.5 \mathrm{psia}$. Calculate the air speed in the wind tunnel.

A major cause of septic shock is the presence in blood of lipopolysaccharide (LPS) from bacteria. Suppose you have available purified LPS and several strain s of mice, each with a mutation that inactivates a particular TLR gene. Explain how you might use these mice to test the feasibility of treating septic shock with a drug that blocks TLR signaling.

Proteins are produced by

a. vesicles.
b. ribosomes.
c. lysosomes.
d. smooth ER.

What type(s) of covalent bond(s) stabilize the tertiary structure of proteins?

Identify the effects of enzymes on food molecules. Which enzymes act on proteins?

List the names of the monomers that make up proteins, complex carbohydrates, and nucleic acids.

Air enters a frictionless, constant area duct with $Ma_{1}$ = 2.0, $T_{0,1}=59^{\circ} \mathrm{F},$ and $p_{0,1}=14.7$ psia. The air is decelerated by heating until a normal shock wave occurs where the local Mach number is 1.5. Downstream of the normal shock, the subsonic flow is accelerated with heating until it chokes at the duct exit. Determine the static temperature and pressure, the stagnation temperature and pressure, and the fluid velocity at the duct entrance, just upstream and downstream of the normal shock, and at the duct exit. Sketch the temperature–entropy diagram for this flow.

Histones are proteins that regulate checkpoints in the mitotic cell cycle.

True or False?

A _____ is a cluster of pigments and proteins that allows plants to absorb light energy and transfer it to electrons.

In each of the following cases, trace the chain of energy transfers (as heat or as work) as well as changes in internal energy. A hole is drilled into a block of metal. When a small amount of water is placed in the drilled hole, steam rises from the hole.

Propose a mechanism for the following reaction, an important step in the laboratory synthesis of proteins: