Answer the following question given this paragraph: Hydrozoa includes nearly 3,500 species, most of which are marine. Most species in this class have both polyp and medusa forms in their life cycle. Many hydrozoans form colonies composed of branches of specialized polyps that share a gastrovascular cavity. Colonies may also be free-floating and contain both medusa and polyp individuals in the colony, as in the Portuguese Man O'War (Physalia) or By-the-Wind Sailor (Velella). Other species are solitary polyps or solitary medusae. The characteristic shared by all of these species is that their gonads are derived from epidermal tissue, whereas in all other cnidarians, they are derived from gastrodermal tissue (Figure 15.14ab). "The Hydrozoa Directory," Peter Schuchert, Museum Geneve, last updated November 2012, http://www. ville-ge. ch/mhng/hydrozoa/hydrozoadirectory. Q: Most hydrozoa have both polyp and what forms in their life cycle? Choices: - hydra - globular - polypoid - medusa A:
medusa
(Question)
Answer the following question given this paragraph: Scientists did not actually see viruses for the first time until the 1930s. That's when the electron microscope was invented. The virus shown in Figure below was the first one to be seen. Q: Scientists did not actually see viruses until what was invented? Choices: - magnifying glass - electronic scale - telescope - electron microscope A:
(Answer)
electron microscope
Ques: Answer the following question given this paragraph: Microwave ovens operate by emitting microwave radiation, which is primarily absorbed by water molecules in food. The absorbed radiation is converted to heat through rapid oscillations of polar water molecules, 28. Q: Microwave ovens use radiation to provide food with what kind of energy? Choices: - magnetic - vibrational - mechanical - heat A:
Ans: heat
(Q).
Answer the following question given this paragraph: birth of dizygotic (or fraternal) twins. Because dizygotic twins develop from two eggs fertilized by two sperm, they are no more identical than siblings born at different times. Much less commonly, a zygote can divide into two separate offspring during early development. This results in the birth of monozygotic (or identical) twins. Although the zygote can split as early as the two-cell stage, splitting occurs most commonly during the early blastocyst stage, with roughly 70100 cells present. These two scenarios are distinct from each other, in that the twin embryos that separated at the two-cell stage will have individual placentas, whereas twin embryos that form from separation at the blastocyst stage will share a placenta and a chorionic cavity. Q: Because dizygotic twins develop from two eggs fertilized by two sperm, they are no more identical than siblings born at what? Choices: - other times of day - different places - other eras - different times A:
(A).
different times
Ques:Answer the following question given this paragraph: The pupil is an opening in the front of the eye. It looks black because it doesn't reflect any light. All the light passes through it instead. The pupil controls the amount of light that enters the eye. It automatically gets bigger or smaller to let more or less light in as needed. Q: What is the opening in the front of the eye called? Choices: - lens - cornea - iris - pupil A:

Ans:pupil
Question: Answer the following question given this paragraph: A human sperm is a tiny cell with a tail. A human egg is much larger. Both cells are mature haploid gametes that are capable of fertilization. What process is shown in this photograph? Notice the sperm with the head piece containing the genetic material, a flagella tail that propels the sperm, and a midpiece of mostly mitochondria, supplying ATP. Q: What part of the sperm contains the genetic material? Choices: - the " body " - the " tail " - the " brain " - the "head" A:
Answer:
the "head"