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A typical anther contains four microsporangia. The microsporangia form sacs or pockets (locules) in the anther (anther sacs or pollen sacs). The two separate locules on each side of an anther may fuse into a single locule. Each microsporangium is lined with a nutritive tissue layer called the tapetum and initially contains diploid pollen mother ...
Bone meal provides phosphorus and calcium to plants, along with a largely inconsequential amount of nitrogen. [4] The N-P-K rating of bone meal is typically 3–15–0 [5] along with a calcium content of around 12% (18% CaO equiv.), [6] although it can vary quite a bit depending on the source from 1–13–0 to 3–22–0. [citation needed]
An anther and its filament together form a typical (or filantherous) stamen, part of the male floral organ. The typical anther is bilocular, i.e. it consists of two thecae. Each theca contains two microsporangia, also known as pollen sacs. The microsporangia produce the microspores, which for seed plants are known as pollen grains.
This protein, which is critical for proper mineralization of bone and dentin, is present in diverse cells of bone and tooth tissues. The protein contains a large number of acidic domains, multiple phosphorylation sites, a functional Arg-Gly-Asp cell attachment sequence , and a DNA binding domain.
A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues.
An endosperm is formed after the two sperm nuclei inside a pollen grain reach the interior of a female gametophyte or megagametophyte, also called the embryonic sac.One sperm nucleus fertilizes the egg cell, forming a zygote, while the other sperm nucleus usually fuses with the binucleate central cell, forming a primary endosperm cell (its nucleus is often called the triple fusion nucleus).
Different types of cells contain different ratios of the two types of ER depending on the activities of the cell. RER is found mainly toward the nucleus of the cell and SER towards the cell membrane or plasma membrane of cell. The outer face of the RER is studded with ribosomes that are the sites of protein synthesis.
Bone morphogenetic proteins (BMPs) are a group of growth factors also known as cytokines and as metabologens. [1] Professor Marshall Urist and Professor Hari Reddi discovered their ability to induce the formation of bone and cartilage, BMPs are now considered to constitute a group of pivotal morphogenetic signals, orchestrating tissue architecture throughout the body.