Describe the chemical composition of DNA
What will be an ideal response?
Organisms contain two types of nucleic acids: DNA and RNA. DNA is found in the nucleus and mitochondria of cells and is made up of subunits known as nucleotides. A nucleotide has three components. The first component is a nitrogen-containing base. There are two types of bases, purines and pyrimidines. DNA's four bases are adenine (A), guanine (G), thymine (T), and cytosine (C). The second component of DNA is a sugar called deoxyribose. The last component is a phosphate group, which is strongly acidic. The components of a nucleotide are assembled by covalently linking one of the four bases to the sugar, which in turn is covalently linked to the phosphate group. Nucleotides are then linked together into polynucleotide chains. DNA contains two polynucleotide chains.
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Select that statement that reflects evidence that directly supports the endosymbiotic theory.
A. Lysosomes contain their own DNA in the form of plasmids. B. The electron transport system is located in the cell membrane in bacteria, while in eukaryotes it is located in the mitochondrial cristae. C. Enzymes for photosynthesis are found embedded in membranes of the Golgi apparatus. D. Glycolysis occurs in the cytoplasm of bacterial cells.
What is the correct order of largest to smallest respiratory structures?
a. Bronchiole - alveolar duct - alveoli b. Alveoli - alveolar duct - bronchiole c. Alveoli - bronchiole - alveolar duct d. Alveolar duct - alveoli - bronchiole e. Bronchiole - alveoli - alveolar duct
Which of the following statements is a correct distinction between autotrophs and heterotrophs?
A) Cellular respiration is unique to heterotrophs. B) Only heterotrophs have mitochondria. C) Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic. D) Only heterotrophs require oxygen.
What is the primary function of the large intestine?
a. to absorb water b. to complete the digestion of fats c. to complete the digestion of protein d. to absorb nutrients