HESI A2 Biology v2 100 Questions and Answers VERIFIED 100% CORRECT

HESI A2 Biology v2 100 Questions and Answers VERIFIED 100% CORRECT 1. Which type of tissue is fat? a. Connective b. Muscle c. Nervous d. Epithelial The correct answer is A. Fat is a type of loose connective tissue called adipose. Its job is to cushion organs. Fat is not made of muscle cells, neurons or epithelial cells. 2. What type of cells have a cell membrane? a. Prokaryotic only b. Eukaryotic only c. Both prokaryotic and eukaryotic d. None of the above The correct answer is C. Cell membranes are present in all types of cells. Its purpose is to hold in the fluids and other components of the cell and protect against external substances and invaders. 3. How is the plasma membrane arranged? a. In a single layer made of proteins b. In a double layer made of proteins c. In a single layer of phospholipids d. In a double layer of phospholipids The correct answer is D. The plasma membrane is made of a phospholipid bilayer that has two layers of phospholipids. The hydrophilic phosphate heads face the outside of the layers and the fatty acid tails face inward, since they are hydrophobic. 4. The head of a phospholipid: a. Is water loving b. Is water fearing c. Is on the outer side of the layer d. Both A and C The correct answer is D. The phosphate head is on the outer part of the bilayer because it is hydrophilic, which means that it can be in contact with water and not react. 5. Cytokinesis happens so that: a. DNA can duplicate b. Organelles can convert energy c. Bacteria can be killed d. Daughter cells can divide The correct answer is D. Cytokinesis happens at the end of mitosis. DNA has already duplicated during mitosis. Cytokinesis must happen so that they cell can divide into the daughter cells. 6. Animal cells use which of the following methods to divide? a. Contractile ring b. Cell plate c. Both d. None of the above The correct answer is A. Animal cells are soft and squishy, which allows them to be pinched apart by a contractile ring, unlike rigid plant cells that must build a cell plate to divide. 7. Why can animal cells use a contractile ring but plant cells cannot? a. Plant cells can use both ways to divide b. Animal cells divide faster so it needs to pinch apart c. Plant cells are too rigid to use a contractile ring The correct answer is C. Animal cells are soft and squishy, which allows them to be pinched apart by a contractile ring, unlike rigid plant cells that must build a cell plate to divide. 8. DNA bases include all but which of the following? a. Adenine b. Thymine c. Uracil d. Cytosine The correct answer is C. Uracil is a base found only in RNA. 9. RNA bases include all but which of the following? a. Adenine b. Thymine c. Uracil d. Cytosine The correct answer is B. RNA uses uracil in place of thymine. Uracil would pair with adenine. 10. Choose the two bases that are purines: a. A b. C c. T d. G The correct answer is A and D. Adenine and guanine are purines, which have two carbon rings. 11. Choose the two bases that have two carbon rings: a. A b. C c. T d. G The correct answer is A and D. Adenine and guanine have two carbon rings and are called purines. 12. C and T are known as: a. Purines b. Pyrimidines c. Both d. None of the above The correct answer is B. Cytosine and thymine are pyrimidines which have one carbon ring. 13. Select the option that best shows complementary base pairing in DNA: a. A and G b. A and C c. A and A d. A and T The correct answer is D. A purine (A) must pair with a pyrimidine (T). This eliminates options A and C. Adenine can only pair with thymine because of their shape and bonding ability. 14. Select the strand of DNA that would match this segment: ACTTGCA a. TGAACGT b. GACCATG c. ACTTGCA d. None of the above The correct answer is A. Purines must pair with pyrimidines in a specific way. A must pair with T; C must pair with G. So the complementary segment is TGAACGT. 15. DNA is stored in: a. The nucleus b. Ribosomes c. Endoplasmic reticulum d. Mitochondria The correct answer is A. Ribosomes produce proteins. The endoplasmic reticulum carries proteins to other parts of the cell. Mitochondria breaks down sugar to create energy. The nucleus stores the DNA and controls the cell. 16. Enzymes can _ reactions a. Catalyze b. Inhibit c. Stop d. None of the above The correct answer is A. Enzymes help to speed up reactions, not to inhibit or stop them. 17. Enzymes are typically _ _. a. Fats b. Proteins c. Sugars d. Neurons The correct answer is B. Enzymes are usually made of proteins, but a few can also be RNA. 18. Which of the following is not true about enzymes? a. They catalyze reactions b. They raise the activation energy needed c. They have an active site d. They are typically proteins The correct answer is B. Enzymes catalyze reactions, have an active site and are typically proteins. They also lower the activation energy needed for a reaction to occur, not raise it. 19. Epithelial cells are: a. Polarized b. Neutral c. Larger than other cells d. None of the above The correct answer is A. Epithelial cells have a top and bottom side, which shows that they are polarized.