Se denomina planeta extrasolar<span> o </span>exoplaneta<span> a un </span>planeta<span> que orbita una estrella diferente al </span>Sol<span> y que, por tanto, no pertenece al </span>sistema solar<span>. Los planetas extrasolares se convirtieron en objeto de investigación científica en el siglo XX. Muchos </span>astrónomos<span> suponían su existencia, pero carecían de medios para identificarlos. La primera detección confirmada se hizo en 1992, con el descubrimiento de varios planetas de masa terrestre orbitando el </span>púlsar Lich.1<span> La primera detección confirmada de un planeta extrasolar orbitando alrededor de una estrella de la </span>secuencia principal<span> (</span>Dimidio<span>), se hizo en </span>1995<span> por los astrónomos </span>Michel Mayor<span> y </span>Didier Queloz.2<span> Desde entonces el número de hallazgos ha crecido año tras año.</span>
Answer:
Chromosomal DNA is packaged inside microscopic nuclei with the help of histones. These are positively-charged proteins that strongly adhere to negatively-charged DNA and form complexes called nucleosomes. ... Nucleosomes fold up to form a 30-nanometer chromatin fiber, which forms loops averaging 300 nanometers in length.
Explanation:
<span>The form of sugar is transported through phloem is sucrose. </span>
They have to eat
They have to hydrate
They have to evolve
They have to adapt
They have to mate
Answer:
C) Primary, tertiary and quaternary levels of protein structure
Explanation:
Primary structure; Covalent bond is present in form of peptide bond in the primary structuture of proteins. The amino acids are held together in the polypeptide chain by peptide bond.
Tertiary structure; Disulfide bonds are present between cysteine amino acids, that keeps the parts of polypeptide chain strongly attached to one another.
Quaternary structure; The Quaternary structure of protein is held together by hydrophobic interaction and disulfide bonds.