Ques:Q: When the helium is gone, the stars become what? Read this paragraph and choose the correct option from the provided answers: When the helium is gone, the stars become white dwarfs. Choices: - comets - yellow dwarfs - red giants - white dwarfs A:

Ans:white dwarfs
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Ques:Q: Physical science can be defined as the study of matter and what? Read this paragraph and choose the correct option from the provided answers: Physical science can be defined as the study of matter and energy. Matter refers to all the "stuff" that exists in the universe. It includes everything you can see and many things that you cannot see, including the air around you. Energy is what gives matter the ability to move and change. Energy can take many forms, such as electricity, heat, and light. Physical science can be divided into chemistry and physics. Chemistry focuses on matter and energy at the scale of atoms and molecules. Physics focuses on matter and energy at all scales, from atoms to outer space. Choices: - time - natural forces - space - energy A:

Ans:energy
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Ques:Q: Called the powerhouses of the cell, what organelles are the site of cellular energy production? Read this paragraph and choose the correct option from the provided answers: The mitochondria are the powerhouses of the cell. Mitochondria are the organelles where cellular energy is produced, providing the energy needed to power chemical reactions. This process, known as cellular respiration , produces energy is in the form of ATP (adenosine triphosphate). Cells that use a lot of energy may have thousands of mitochondria. Choices: - nucleus - mitosis - cell wall - mitochondria A:

Ans:mitochondria
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Ques:Q: After the amino acid molecule has been bound to its what, protein synthesis can take place? Read this paragraph and choose the correct option from the provided answers: How can a molecule containing just 4 different nucleotides specify the sequence of the 20 amino acids that occur in proteins? If each nucleotide coded for 1 amino acid, then obviously the nucleic acids could code for only 4 amino acids. What if amino acids were coded for by groups of 2 nucleotides? There are 42, or 16, different combinations of 2 nucleotides (AA, AU, AC, AG, UU, and so on). Such a code is more extensive but still not adequate to code for 20 amino acids. However, if the nucleotides are arranged in groups of 3, the number of different possible combinations is 43, or 64. Here we have a code that is extensive enough to direct the synthesis of the primary structure of a protein molecule. The genetic code can therefore be described as the identification of each group of three nucleotides and its particular amino acid. The sequence of these triplet groups in the mRNA dictates the sequence of the amino acids in the protein. Each individual three-nucleotide coding unit, as we have seen, is called a codon. Protein synthesis is accomplished by orderly interactions between mRNA and the other ribonucleic acids (transfer RNA [tRNA] and ribosomal RNA [rRNA]), the ribosome, and more than 100 enzymes. The mRNA formed in the nucleus during transcription is transported across the nuclear membrane into the cytoplasm to the ribosomescarrying with it the genetic instructions. The process in which the information encoded in the mRNA is used to direct the sequencing of amino acids and thus ultimately to synthesize a protein is referred to as translation. Before an amino acid can be incorporated into a polypeptide chain, it must be attached to its unique tRNA. This crucial process requires an enzyme known as aminoacyl-tRNA synthetase (Figure 19.12 "Binding of an Amino Acid to Its tRNA"). There is a specific aminoacyl-tRNA synthetase for each amino acid. This high degree of specificity is vital to the incorporation of the correct amino acid into a protein. After the amino acid molecule has been bound to its tRNA... Choices: - base - RNA receptor - dna molecule - trna carrier A:

Ans:
trna carrier
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