The mesencephalon gives rise to the midbrain and aqueduct of the midbrian(cerebal aqueduct). Both the prosencephalon and rhombencephalon develops in to the metencephalon and myelencephalon. The telencephalon develops into the cerebrum and lateral ventricles. The diencephalon forms the thalamus, hypothalamus, and epithalamus.

5 0

3 years ago

Rhodobacter cells perform photosynthesis in the presence of light and grow heterotrophically in the dark. After being cultured i

Marrrta [24]

Answer:

Phenotypic changes:

When Rhodobacter is cultured in total darkness for multiple generations, the ability to produce it's own photopigment reduces with time with little or no ability to undergo its own photosynthesis due to absence of enzymes or pigment for photosynthesis.

It becomes expensive for the Rhodobacter to undergo photosynthesis. This allows mutants that can grow in the dark to take over from the culture grown in the dark.

Evolutionary processes:

It's natural selection that allows the fittest organism to survive. As in the case of the mutants

5 0

3 years ago

What would happen to an egg that had a nonfunctional chorion?

Firlakuza [10]

Answer:

a. The embryo would suffocate or dehydrate.

Explanation:

Chorion is one of the four extraembryonic membranes that cover the embryo inside the egg. Chorion develops into the part of placenta-derived from the fetus.

Trophoblast develops into chorion during pre-embryonic development. Once formed, the chorion develops villi that are required for the exchange of material, specifically the respiratory gases, between the mother and fetus.

If an egg had nonfunctional chorion, the developing embryo will not get the supply of gases. In the absence of gas exchange between mother and embryo, the embryo will die of suffocation.

Chorion is also involved in the development of the placenta which in turn is the organ of the exchange of nutrients and gases and removal of toxic material.

Nonfunctional chorion would not support the placenta formation and the embryo will not get the supply of nutrients and water.

8 0

3 years ago

Which of these statements are accurate? Hexokinase is a type of transferase that catalyzes the transfer of a phosphoryl group fr

Agata [3.3K]

Answer:

A. The conformational shift that occurs when glucose, but not water, enters the active site prevents water from hydrolyzing ATP. True

B. Hexokinase consists of two domains, or lobes, that come together when glucose and the MgATP2–MgATP2– complex are bound. True

C. Hexokinase is a type of transferase that catalyzes the transfer of a phosphoryl group from ATP to a hexose. True

Explanation:

A. Hexokinase suffers and conformational changes by binding glucose in a reaction that prevents ATP hydrolysis.

B. Hexokinase is an enzyme with two domains that function by binding to the substrate (i.e., glucose). The region linking both protein domains is responsible for the catalytic activity.

C. Hexokinase is a type of transferase that catalyzes the transfer of a phosphoryl group from ATP to a hexose. During the first stage of glycolysis, the hexokinase transfers one phosphorous group from magnesium-ATP (Mg-ATP) to one hexose molecule, such as fructose, mannose or glucose.

False statements:

- Most kinases require the presence of a monovalent metal ion cofactor to prevent ATP hydrolysis. False: In canonical kinases, conserved amino acids bind to divalent metal ions before the transference of the phosphate group to their substrates.

- Hexokinase is found in the mitochondrial membrane. False: Hexokinase is found in the cytosol.

- Hexokinase transfers the terminal phosphate of ATP to carbon 3 of glucose. False: Hexokinase catalyzes the transfer of the terminal phosphate ATP to form glucose 6-phosphate.

5 0

2 years ago