Ques:Q: In addition to spiral cleavage, protostomes also undergo which other form of cleavage? Read this paragraph and choose the correct option from the provided answers: There is a second distinction between the types of cleavage in protostomes and deuterostomes. In addition to spiral cleavage, protostomes also undergo determinate cleavage. This means that even at this early stage, the developmental fate of each embryonic cell is already determined. A cell does not have the ability to develop into any cell type. In contrast, deuterostomes undergo indeterminate cleavage, in which cells are not yet pre-determined at this early stage to develop into specific cell types. These cells are referred to as undifferentiated cells. This characteristic of deuterostomes is reflected in the existence of familiar embryonic stem cells, which have the ability to develop into any cell type until their fate is programmed at a later developmental stage. Choices: - straight - diagonal - dispersive - determinate A:

Ans:determinate
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Ques:Q: What do chemical reactions need to be activated? Read this paragraph and choose the correct option from the provided answers: Chemical reactions also need energy to be activated. They require a certain amount of energy just to get started. This energy is called activation energy . For example, activation energy is needed to start a car engine. Turning the key causes a spark that activates the burning of gasoline in the engine. The combustion of gas won't occur without the spark of energy to begin the reaction. Choices: - food - space - products - energy A:

Ans:energy
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Ques:Q: What process determines which of two fossils is older or younger than the other? Read this paragraph and choose the correct option from the provided answers: Relative dating determines which of two fossils is older or younger than the other, but not their age in years. Relative dating is based on the positions of fossils in rock layers. Lower layers were laid down earlier, so they are assumed to contain older fossils. This is illustrated in Figure below . Choices: - differential dating - difference dating - curve dating - relative dating A:

Ans:relative dating
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Ques:Q: What begins when a neuron receives a chemical stimulus? Read this paragraph and choose the correct option from the provided answers: A nerve impulse begins when a neuron receives a chemical stimulus. The impulse travels down the axon membrane as an electrical action potential to the axon terminal. The axon terminal releases neurotransmitters that carry the nerve impulse to the next cell. Choices: - a induce impulse - a metabolism impulse - nerve reaction - a nerve impulse A:

Ans:
a nerve impulse
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