HESI A2 V2 BIOLOGY EXAM WITH RATIONALE

HESI A2 V2 BIOLOGY EXAM WITH RATIONALE

1.    Anaerobic respiration happens in    _ because    _ .
a.    Animals; they need energy
b.    Plants; they use sunlight
c.    Bacteria; they live in environments with low oxygen.
d.    None of the above
The correct answer is C. Animals and plants both use aerobic respiration because they have access to oxygen. Bacteria typically live in environments with little to no oxygen and must still produce energy to survive.

2.    All bacteria are bad and always cause infections.
a.    True
b.    False
The correct answer is B. Bacteria can be good, such as the bacteria in the intestines. This bacterium can become problematic if it travels to a location other than where it belongs. Pathogenic bacteria are bad and can cause infections, but not all bacteria are this type.
 
3.    Which of the following is not true about antibiotics?
a.    They can interfere with the bacteria’s ability to survive
b.    They can affect how bacteria multiply
c.    They can cause more bacteria to grow
d.    They only work on bacteria
The correct answer is C. Antibiotics only work on bacteria by either blocking its ability to grow or multiply, or completely killing the bacteria cells.

4.    Prokaryotic cells:
a.    Have a nucleus
b.    Have a capsule
c.    Have membrane bound organelles
d.    Cannot move on their own
The correct answer is B. Prokaryotic cells are simple, single celled organisms. They do not have a nucleus or membrane bound organelles. This type of cell can move on its own with a flagella or small hair-like fibers.

5.    Select the cell parts that are present in plant cells but not animal cells (there may be more than one answer):
a.    Cell membrane
b.    Cell wall
c.    Ribosome
d.    Chloroplast
The correct answer is B and D. Both plant and animal cells have a cell membrane and ribosomes, however only plant cells have a cell wall and chloroplasts. The cell wall is necessary for maintaining the shape and structure of the plant. Chloroplasts are necessary for photosynthesis.

6.    A patient receives an antibiotic for symptoms of the flu. Why doesn’t the medication work?
a.    The medication is for a different type of flu.
b.    The medication is not suitable for treating the flu.
c.    The medication is not a strong enough dosage amount to cure the patient.
d.    None of the above
The correct answer is B. Antibiotics are used for treating bacterial infections, but the flu is caused by a virus. Although symptoms can be similar in case of a cold (bacteria) or the flu (virus), viruses cannot be treated using antibiotics.

7.    The nucleus is important in a cell because:
a.    It stores the DNA
b.    It supports the cell
c.    It makes protein
d.    It makes energy out of food
The correct answer is A. The nucleus is the “brain” of the cell and stores the DNA. A cell wall supports the cell (only if it is a plant). The ribosomes make protein and the mitochondria makes energy.

8.    Cellular respiration happens so that
a.    Cells can copy DNA
b.    Cells can breathe
c.    Cells can convert nutrients to energy
d.    Cells can divide
The correct answer is C. The term respiration typically triggers thoughts of breathing, but in this case, it is referring to the process cells undergo to convert nutrients into ATP. Copying DNA is transcription and translation. Cells themselves cannot breathe. Cell division is mitosis or meiosis, depending on the type of cell.

9.    Epithelial tissue can be found in:
a.    Organ lining
b.    Heart muscle
c.    Tendons
d.    Spinal cord
The correct answer is A. Epithelial tissue is found in skin and all of the linings within the body. Heart muscle is muscle tissue, tendons are connective tissue and the spinal cord is nervous tissue.

10.    What are the three types of muscle tissue?
a.    Cardiac, spinal, stomach
b.    Smooth, skeletal, cardiac
c.    Neuron, epithelial, collagen
d.    None of the above
The correct answer is B. Smooth muscle is found in organs like the stomach, where it is involuntarily controlled. Skeletal muscle is found in voluntary muscles, like the bicep or quadriceps. Cardiac muscle is found only in the heart walls and works involuntarily to make the heart beat and pump blood.
 
11.    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.

12.    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.

13.    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.

14.    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.

15.    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.

16.    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.
 
17.    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.

18.    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.

19.    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.

20.    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.

21.    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.

22.    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.

23.    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.