HESI A2 Biology Exam Questions
with Verified Answers Graded A+
1. water molecule consists of - ANSWER two hydrogen atoms covalently
bonded to one oxygen atom
2. What process do cells in the tip of a plants roots undergo to increase in
number? - ANSWER Mitosis
3. How do RNA and DNA derive their names? - ANSWER From the sugar
each contains
4. If a disease is carried on the dominant allele, only the aa combination of
recessive genes represents a disease free offspring. - ANSWER 1 out of 4 or
25% are predicted to be disease free
5. If bacteria are placed in a strong solution of salt water, they will shrink as
water moves out of the bacteria. What is this process called? - ANSWER
Osmosis, because if cells are placed in a very salty solution, water molecules
can diffuse across the cell membrane to move water from an area of greater
concentration of water molecules (inside the cells) to an area with a lesser
concentration of water molecules(the solution of salt water)
6. Which animal has an open transport system? - ANSWER Grasshopper
7. How does an enzyme work on a chemical reaction that occurs in a substrate?
- ANSWER An enzyme speeds up the chemical reaction, because enzymes
, are catalysts that speed up reactions. They do this by lowering the amount of
energy needed to begin the reaction.
8. Where is the ovary located in a flowering plant? - ANSWER Pistil
9. Two organisms live in a relationship from which both benefit - ANSWER
Mutualism, both species receive mutual benefit
10.Which gives the order of four taxonomic categories from least to most
specific? - ANSWER Kingdom phylum class order family genus species
11.Which molecules contain only carbon, hydrogen, and oxygen? - ANSWER
Carbohydrates and lipids
12.Which structure is found in Protists but not in monerans? - ANSWER Golgi
apparatus
13.How does yeast reproduce? - ANSWER Budding
14.most significant aspect of water is - ANSWER the polarity of its bonds that
allows for hydrogen bonding between molecules
15.specific heat - ANSWER the amount of heat necessary to raise the
temperature of 1 gram of that molecule 1 degree celsius
16.water has high specific heat due to - ANSWER the extent of hydrogen
bonding between water molecules, which allows waters to resist shifts in
temperature (ability of oceans or large bodies of water to stabilize climates)
,17.glycolysis - ANSWER -first step of metabolism of food cellular energy is
the conversion of glucose to pyruvate
-takes place in the cytosol of the cell and produces two molecules of ATP, two
molecules of pyruvate and two molecules of NADH
18.citric acid cycle (Krebs Cycle) - ANSWER -in step 2 the pyruvate is
transported into a mitochondrion and used in the first of series of reactions
-takes place in the mitochondria
-two ATP molecules, 6 molecules of carbon dioxide and 6 NADH molecules
are produced
19.electron transport chain - ANSWER 3rd step begins with the oxidation of
the NADH molecules to produce oxygen and finally to produce water
-for every glucose molecule 28-32 ATP molecules can be produced
20.adhesion - ANSWER the ability of water to bond to or attract other
molecules or substances (when water is sprayed onto the wall, some of it
sticks to the wall)
21.when water freezes it forms - ANSWER lattice crystals; causing the
molecules to spread apart, resulting in the phenomenon of ice floating
22.polarity of water allows it to act as an - ANSWER versatile solvent (used to
dissolve a number of different solvents)
23.carbohydrates - ANSWER longs chains, or polymers of sugar
, -used for storage, structure, and energy
-the backbone of important molecules such as DNA and RNA
24.lipids - ANSWER known as fats, but specifically they are fatty acids,
phospholipids, and steroids
25.fatty acids - ANSWER Vary greatly but simply are grouped into two
categories: saturated and unsaturated
26.saturated fats - ANSWER contain no double bonds in their hydrogen tail
-solids at room temp
-lead to cardiovascular problems associated with diets
27.unsaturated fats - ANSWER have one or more double bonds
-liquid at room temperature
28.phospholipids - ANSWER -consist of two fatty acids of varying length
bonded to a phosphate group
-phosphate group is charged and therefore polar and soluble in water
29.steroids - ANSWER -component of membranes precursors to significant
hormones and drugs
30.proteins - ANSWER -most significant contributor to cellular function
polymeres of 20 molecules called amino acids
31.-complex, consist of several structural types and are the largest biological
molecule
with Verified Answers Graded A+
1. water molecule consists of - ANSWER two hydrogen atoms covalently
bonded to one oxygen atom
2. What process do cells in the tip of a plants roots undergo to increase in
number? - ANSWER Mitosis
3. How do RNA and DNA derive their names? - ANSWER From the sugar
each contains
4. If a disease is carried on the dominant allele, only the aa combination of
recessive genes represents a disease free offspring. - ANSWER 1 out of 4 or
25% are predicted to be disease free
5. If bacteria are placed in a strong solution of salt water, they will shrink as
water moves out of the bacteria. What is this process called? - ANSWER
Osmosis, because if cells are placed in a very salty solution, water molecules
can diffuse across the cell membrane to move water from an area of greater
concentration of water molecules (inside the cells) to an area with a lesser
concentration of water molecules(the solution of salt water)
6. Which animal has an open transport system? - ANSWER Grasshopper
7. How does an enzyme work on a chemical reaction that occurs in a substrate?
- ANSWER An enzyme speeds up the chemical reaction, because enzymes
, are catalysts that speed up reactions. They do this by lowering the amount of
energy needed to begin the reaction.
8. Where is the ovary located in a flowering plant? - ANSWER Pistil
9. Two organisms live in a relationship from which both benefit - ANSWER
Mutualism, both species receive mutual benefit
10.Which gives the order of four taxonomic categories from least to most
specific? - ANSWER Kingdom phylum class order family genus species
11.Which molecules contain only carbon, hydrogen, and oxygen? - ANSWER
Carbohydrates and lipids
12.Which structure is found in Protists but not in monerans? - ANSWER Golgi
apparatus
13.How does yeast reproduce? - ANSWER Budding
14.most significant aspect of water is - ANSWER the polarity of its bonds that
allows for hydrogen bonding between molecules
15.specific heat - ANSWER the amount of heat necessary to raise the
temperature of 1 gram of that molecule 1 degree celsius
16.water has high specific heat due to - ANSWER the extent of hydrogen
bonding between water molecules, which allows waters to resist shifts in
temperature (ability of oceans or large bodies of water to stabilize climates)
,17.glycolysis - ANSWER -first step of metabolism of food cellular energy is
the conversion of glucose to pyruvate
-takes place in the cytosol of the cell and produces two molecules of ATP, two
molecules of pyruvate and two molecules of NADH
18.citric acid cycle (Krebs Cycle) - ANSWER -in step 2 the pyruvate is
transported into a mitochondrion and used in the first of series of reactions
-takes place in the mitochondria
-two ATP molecules, 6 molecules of carbon dioxide and 6 NADH molecules
are produced
19.electron transport chain - ANSWER 3rd step begins with the oxidation of
the NADH molecules to produce oxygen and finally to produce water
-for every glucose molecule 28-32 ATP molecules can be produced
20.adhesion - ANSWER the ability of water to bond to or attract other
molecules or substances (when water is sprayed onto the wall, some of it
sticks to the wall)
21.when water freezes it forms - ANSWER lattice crystals; causing the
molecules to spread apart, resulting in the phenomenon of ice floating
22.polarity of water allows it to act as an - ANSWER versatile solvent (used to
dissolve a number of different solvents)
23.carbohydrates - ANSWER longs chains, or polymers of sugar
, -used for storage, structure, and energy
-the backbone of important molecules such as DNA and RNA
24.lipids - ANSWER known as fats, but specifically they are fatty acids,
phospholipids, and steroids
25.fatty acids - ANSWER Vary greatly but simply are grouped into two
categories: saturated and unsaturated
26.saturated fats - ANSWER contain no double bonds in their hydrogen tail
-solids at room temp
-lead to cardiovascular problems associated with diets
27.unsaturated fats - ANSWER have one or more double bonds
-liquid at room temperature
28.phospholipids - ANSWER -consist of two fatty acids of varying length
bonded to a phosphate group
-phosphate group is charged and therefore polar and soluble in water
29.steroids - ANSWER -component of membranes precursors to significant
hormones and drugs
30.proteins - ANSWER -most significant contributor to cellular function
polymeres of 20 molecules called amino acids
31.-complex, consist of several structural types and are the largest biological
molecule
