The assembly and arrangement of chromosomes, structures composed of a very long molecule of DNA and associated proteins that carries hereditary information.

Any process that modulates the frequency, rate or extent of the directed movement of a motile cell or organism towards a higher concentration in a concentration gradient of a specific chemical.

Catalysis of the reaction: NAD(P)+ + 17-alpha,20-alpha-dihydroxypregn-4-en-3-one = NAD(P)H + 17-alpha-hydroxyprogesterone.

positive regulation of positive chemotaxis

Any process that activates or increases the rate of the directed movement of a motile cell or organism towards a higher concentration in a concentration gradient of a specific chemical.

regulation of transcription by carbon catabolites

Any process involving carbon catabolites that modulates the frequency, rate or extent of transcription.

The formation from simpler components of a vitamin, one of a number of unrelated organic substances that occur in many foods in small amounts and that are necessary in trace amounts for the normal metabolic functioning of the body.

Any process that initiates the directed movement of a motile cell or organism towards a lower concentration in a concentration gradient of a specific chemical.

The chemical reactions involving a nucleobase, a nitrogenous base that is a constituent of a nucleic acid, e.g. the purines: adenine, guanine, hypoxanthine, xanthine and the pyrimidines: cytosine, uracil, thymine.

The formation from simpler components of purine bases, one of the two classes of nitrogen-containing ring compounds found in DNA and RNA, which include adenine and guanine.

Any collagen polymer which links one collagen assembly, such as a collagen fibril or sheet, to other structures.

Catalysis of the reaction: 3-hydroxyanthranilate + O2 = 2-amino-3-carboxymuconate semialdehyde.

Any collagen polymer in which collagen triple helices associate to form sheet-like networks.

Any process that modulates the frequency, rate or extent of embryonic development.