Answer:
Explanation:
A. Inactivation of an enzyme that degrades M-Cyclin.
M-phase cyclins form M-CDK complexes and drive the cell's entry into mitosis from G2 phase as non-degradation of M-Cyclin resulting from inactivated enzyme can only result in constitutive entry of the cell in to M phase instead cell cycle being arrested at G2 phase,
B. Inactivation of the Wee-1 kinase.
Wee1 is a nuclear kinase that plays a key role in regulating cell cycle progression. Wee1 inhibits the entry of the cell into M phase by inhibiting Cdk1. Wee1 phosphorylates Cdk1 there inhibiting the kinase activity of Cdk1 which is essential for progression from G2 to M phase. As such any mutation of wee1, and the resulting loss of activity will result in premature entry of cells into M phase instead of getting arrested at the G2 phase resulting in smaller yeast cell.
C. Inactivation of the Cdc25 phosphatase
CDC25 phosphatases removes inhibitory phosphate residues from cyclin dependent kinases resulting in the activation of CDKs which causes the cells in G2 phase to entry to M phase. Mutation in CDC25 phosphates removes the ability of CDC25 to remove phosphate residues from CDKs thus preventing the entry into M-phase.
Therefore, mutant phenotype of cell cycle arrest prior to M phase can only result form mutation in
Cdc25 phosphatase(option 3)
Hello,
Light dependent reactions are reactions of photosynthesis that use energy from light and water to produce ATP and oxygen that is released into the atmosphere. Calvin Cycle / Light independent reactions of <span>photosynthesis </span><span>convert carbon dioxide and other compounds into glucose.
Faith xoxo</span>
Gregor Mendel laid the groundwork for the science of genetics by developing his Mendelian inheritance, which <span> is a type of biological inheritance.</span><span>
In Mendelian genetics, genetic characteristics that are not expressed in an organism are said to be nondominant.
</span><span>In contrast those genetic characteristics that are expressed in an organism are said to be dominant.
</span>
Answer:
B
Explanation:
The dermis is the layer of skin below the epidermis. Below the dermis is the subcutaneous layer. It contains connective tissue from collagen and elastic fibers giving skin its elasticity. It contains nerve fibers sensitive to heat and touch. Glands - like sebaceous & sweat glands, hair follicles, and blood capillaries that supply the skin, are found in this layer.
B. Storage of water - the central vacuole functions to store water in plant cells
