Answer the following question given this paragraph: Because chemical changes result in different substances, they often cannot be undone. Some chemical changes can be reversed, but only by other chemical changes. Q: By what kind of change can a chemical change be reversed? Choices: - another carbon change - another thermal change - another radioactive change - another chemical change A:
another chemical change
Answer the following question given this paragraph: The first eight phyla listed in Table above include only invertebrate animals. Invertebrates are animals that lack a vertebral column , or backbone. The last phylum in the table, the Chordata, also includes many invertebrate species. Tunicates and lancelets are both invertebrates. Altogether, invertebrates make up at least 95 percent of all animal species. The remaining animals are vertebrates. Vertebrates are animals that have a backbone. All vertebrates belong to the phylum Chordata. They include fish, amphibians, reptiles, birds, and mammals. Q: What is the name for animals that have a backbone? Choices: - mammals - skeletates - invertebrates - vertebrates A:
vertebrates
Q: Answer the following question given this paragraph: Elongation is the addition of nucleotides to the mRNA strand. Q: Elongation is the addition of what to the mrna strand? Choices: - codons - glycine - filaments - nucleotides A:
A: nucleotides
Question: Answer the following question given this paragraph: Pressure is defined as the force per unit area on a surface. Q: Pressure is defined as the force per unit area on? Choices: - weight - gravity - speed - surface A:
Answer: surface
*Question*
Answer the following question given this paragraph: The marsupial embryo is nourished inside the uterus with food from a yolk sac instead of through a placenta. The yolk sac stores enough food for the short period of time the embryo remains in the uterus. After the embryo is born, it moves into the mother's pouch, where it clings to a nipple. It remains inside the pouch for several months while it continues to grow and develop. Even after the offspring is big enough to leave the pouch, it may often return to the pouch for warmth and nourishment ( Figure below ). Eventually, the offspring is mature enough to remain outside the pouch on its own. Q: A yolk sac replaces what structure for nourishing a marsupial embryo? Choices: - uterus - glucose - Stomach - placenta A:
**Answer**
placenta
Q: Answer the following question given this paragraph: Vertebrates have an adaptive immune system. The immune system is the organ system that defends the body from pathogens and other causes of disease. Being adaptive means that the immune system can learn to recognize specific pathogens. Then it can produce tailor-made chemicals called antibodies to attack them. This allows the immune system to launch a rapid attack whenever the pathogens invade the body again. Q: Which organ system defends the body from pathogens and other causes of disease? Choices: - digestion system - nervous system - respiratory system - immune system A:
A: immune system