People with HIV are unable to fight off these rare diseases because they have a weakened immune system.
Answer:
C
Explanation:
The correct sequence of these Genes on the X chromosome is sc v s (v in the middle)
Echinoderms, they are among the most common invertebrate animals in the marine environment of virtually any part of the world, among them we can find species such as sea cucumber , salmon and cod fish, they have chamois cloth like outer layer, then we have the Crinoids, another example of marine species with feather, popularly they are called sea lilies and feathery stars, they have a solid calcite skeleton; they were so abundant in the paleozoic seas that their remains formed large limestone thicknesses.
All of the above i think.
<span>Insects are found in almost all ecosystems on Earth, with the rarity being oceans. While some species, such as coconut crabs, sand hoppers, woodlice and pill bugs dwell on land, crustaceans are generally found in water — and usually oceanic — regions. Adapting to their habitat, many insect species evolved wings — two pairs for most and one pair for others. A tracheal system is also present for breathing. Crustaceans, on the other hand, breathe using gill-like mechanisms.</span>
