Q: What is considered to be a unique feature of echinoderms? Read this paragraph and choose the correct option from the provided answers: A unique feature of echinoderms is their water vascular system. This is a network of canals that extends along each body part. In most echinoderms, the canals have external projections called tube feet (see Figure below ). The feet have suckers on the ends. Muscle contractions force water into the feet, causing them to extend outward. As the feet extend, they attach their suckers to new locations, farther away from their previous points of attachment. This results in a slow but powerful form of movement. The suckers are very strong. They can even be used to pry open the shells of prey. Choices: - oil vascular system - air vascular system - iron vascular system - water vascular system A:
water vascular system

Q: The cycle of copper reacting is a good example of what principle? Read this paragraph and choose the correct option from the provided answers: A series of chemical reactions where an initial amount of copper reacts with nitric acid, goes into solution, and disappears. Then a series of reactions proceed, only to have the copper metal recovered. The copper cycle is a good illustration of how mass is conserved in a given chemical reaction. Choices: - law of inertia - conservation of energy - conservation of momentum - conservation of mass A:
conservation of mass

Q: Like a blanket on a sleeping person, greenhouse gases act as what for the planet? Read this paragraph and choose the correct option from the provided answers: Like a blanket on a sleeping person, greenhouse gases act as insulation for the planet. The warming of the atmosphere is because of insulation by greenhouse gases. Greenhouse gases are the component of the atmosphere that moderate Earth's temperatures. Choices: - ventilation - plastic - Exterior Coverings - insulation A:
insulation

Q: Androgen secretion and sperm production are both controlled by hypothalamic and which other hormones? Read this paragraph and choose the correct option from the provided answers: Choices: - Testes - salivary - adrenal - pituitary A:
pituitary