Why is a high-dose flu shot available for people 65 and older? As people get older, their natural immune defenses can weaken and they can get sick more easily. The high-dose flu shot contains four times more antigen (active ingredient) than a regular flu shot. This helps older people develop a better immune response, gives better protection against the flu and also helps prevent flu-related complications.
Dogfish sharks are fish; fish are vertebrates, and all vertebrates have bilateral symmetry. This means they have symmetry across one plane (known as the sagittal plane, and directly down the centre of their body), which means one side of their body approximately mirrors the other side.n the northeast Pacific Ocean estimates of the age at maturity for female spiny dogfish have ranged from 20 years and 3 feet (92cm) to 35.5 years and 3.1 feet (94cm. 2 people found this useful.
An echinoderm is a sea animal that has a hard spiny shell, or exoskeleton. Echinoderms display radial symmetry, having 5 similar body extensions from a central point.  The se â¦ ven classes of echinoderms are brittle stars, basket stars, sea urchins, sand dollars, sea lilies, feather stars, and sea cucumbers.chinoderms have swimming larvae that are bilaterally symmetrical, with left and right sides, but they do not 'develop into' bottom-living adult echinoderms, which are radiall â¦ y symmetrical, often star-shaped. The juvenile (young adult), radial from the start, grows from a group of stem cells within the larva.