Answer: Alexandrium catenella is a species of dinoflagellates. Alexandrium has two flagella that enable it to swim. While one flagellum encircles the cell causing the cell to rotate and move forward, the other extends behind the cell and controls the direction.
The cell wall is composed of cellulose Theca.
Length 20 - 48 μm, width 18 - 34 μm
Yellow-green to orange-brown
Forms chains of 2, 4 or 8 cells
Cellulose is a straight chain polysaccharide which is made up of glucose molecules that are joined together by beta 1,4 glycosidic bonds. Cellulose is the principal structural material of plants and plants use it to build strong structures. For instances, the rigid cell wall of plant cells is made up of cellulose.
Thus, the correct option is D.
By using both of these schemes, energy source and locomotion, amoeboids can be classified properly. Both schemes play an important part of amoeboid’s taxonomy classification because these organisms changes its shape when feeding. Amoebas are traditionally classified under sub-phylum Sarcodina, single-celled with pseudopods (use for locomotion) but recent studies show that they are not monophyletic and actually belong to other groups of organisms — with locomotion and source of nutrients as basis.
Answer:
Homologous pairs of cells are present in meiosis I and separate into chromosomes before meiosis II. In meiosis II, these chromosomes are further separated into sister chromatids. Meiosis I includes crossing over or recombination of genetic material between chromosome pairs, while meiosis II does not.
Explanation:
Brainliest please?