Answer:
Both facilitated diffusion and active transport are selective processes. Only selective molecules are allowed to cross the membrane. They utilize carrier proteins to move across the membrane.
Explanation:
Diffusion is the process by which molecules move across a membrane respective of the concentration gradient. The plasma membrane is a <em>selectively permeable membrane</em> which allows specific molecules to move across the concentration gradient.
Molecules migrate from a region of higher concentration to a lower concentration in case of diffusion. It can be classified into simple diffusion and facilitated diffusion. These are examples of <em>passive transport</em>.
In facilitated diffusion molecules move across the concentration gradient with the help of <em>carrier proteins or channel proteins</em>. The carrier proteins bind to the molecule which has to be transported and change conformation to allow it to cross the membrane. For example glucose molecule is carried across through <em>GLUT transporter</em>. <em>Channel proteins</em> open a channel inside the membrane and molecules get transported across the gradient.
Active transport carries molecules against the concentration gradient with the assist of energy. ATP hydrolysis is utilized to generate energy. As a result of active transport, the molecules are aggregated on one side of the membrane.
The elbow (or olecranon joint) is the part of the upper limb between the arm and forearm. This articulation includes the region of the "elbow fold" (or ulnar fossa). It is a synovial joint complex of the upper human limb connecting the arm to the forearm. He thus unites three bones between them: the radius, the ulna and the humerus.
<span>The ulna is a long bone of the forearm, located at its inner side while the radius, the second bone of the forearm, is located at the level of the outer part (the same side of the thumb)</span>
The separation of the sister chromatids during the cell division occurs in the anaphase in mitosis and anaphase II in meiosis.
During the anaphase in mitosis, and the anaphase II of the meiosis, the chromosomes aligned at the center of the nucleus separates and the sister chromatids of the chromosomes starts moving towards the opposite poles as the spindle fibers starts contracting.
