Autotrophs are organisms that produce complex organic compounds (fats, carbohydrates, proteins). Ex: planta, algae and some bacteria.
Heterotrophs are organisms that can’t produce their own foods (organic compounds) so they rely on eating other organisms (plants or animals) to obtain their energy. Ex: dogs, humans, cats, giraffes, ect.
Answer:
Hydrogen bonds.
Explanation:
The DNA double helix is held together by two main forces: hydrogen bonds between complementary base pairs inside the helix and the Van der Waals base-stacking interaction.
I believe it's called a sex-linked trait, if I'm remembering correctly. This is because men do not have an X chromosome, therefore it would be linked to females.
Answer:
undergo irreversible repression
Explanation:
Cellular differentiation refers to the process by which one cell and/or cell population divides and differentiates into more specialized cells. During cell fate differentiation, epigenetic marks modify chromatin structure in order to hamper the accessibility of the transcriptional machinery and transcriptional factors to different genes, which are irreversibly repressed. These epigenetic marks include DNA methylation and histone modifications (e.g., histone acetylation, histone methylation, etc). For example, it has been shown that DNA methylation and histone H3 lysine 27 tri‐methylation (H3K27me3) are epigenetic repressive marks on genomic regions that play a major role in gene expression programs during cell fate differentiation.