USABO OPEN Exam 4 Questions with
100% Correct Answers Latest
Versions 2025 Graded A+
The order of normal blood flow through the human heart is - correct answer✔✔ right atrium, right
ventricle, lungs, left atrium, left ventricle, body
Allopatric speciation refers to species formed after which type of separation: - correct answer✔✔
geographic
Which two functional groups are always found in amino acids? - correct answer✔✔ Carboxyl and amine
Movement of ions across the membrane from higher to lower concentrations through a channel protein
is an example of - correct answer✔✔ Facilitated diffusion
Which group of plants has vascular tissue but does not produce seeds?
I. Mosses
II. Ferns
III. Gymnosperms - correct answer✔✔ II
Which of the following is true for transport in xylem? - correct answer✔✔ Movement through xylem
depends mainly on transpiration
Predation is considered a _________ interaction, while Mutualism is considered a ___________
interaction. - correct answer✔✔ +/-, +/+
,Which of the following organisms is INCORRECTLY paired with its trophic level? - correct answer✔✔
Beetle - secondary consumer
Which of the following is an example of habituation? - correct answer✔✔ Hydra initially contract when
gently touched, but soon stop responding.
Suppose gene "C" is the gene for color. Its dominant allele has the effect of allowing the production of
fur color while its recessive allele interrupts color production. At another locus, there exists another
gene that influences color, at which black (B) is dominant to brown (b). What is the relationship
between these genes called? - correct answer✔✔ Epistatic
During migrations, some birds use which of the following as reference frameworks?
I. The sun
II. Constellations
III. Earth's magnetic field - correct answer✔✔ I,II, and III
Generally, there are more species per square kilometer in which of the following types of ecosystem? -
correct answer✔✔ Coral reef
RUBP is used and PGA is formed in: - correct answer✔✔ dark reaction (Calvin cycle) of photosynthesis
Which is TRUE of the dark reaction (Calvin cycle) of photosynthesis? - correct answer✔✔ It uses carbon
dioxide
In the fern life cycle, the dominant generation is the: - correct answer✔✔ diploid sporophyte
Assume a person is placed on cortisol medication, a glucocorticoid. How would you expect the rates of
ACTH and CRF hormone production to change in the person? - correct answer✔✔ ACTH production
would decrease, CRF production would increase
Carbon particles were injected into the blood of mice. In which of the following places would you most
likely find the particles? - correct answer✔✔ In monocytes of the spleen
, Kidneys provide osmoregulation for the body. Consumption of which nutrient creates the greatest need
for osmoregulation? - correct answer✔✔ Protein
During translation in prokaryotes, the ribosome binds to: - correct answer✔✔ the Shine-Dalgarno
sequence
The quaternary structure of a protein is determined by: - correct answer✔✔ .interactions between
amino acids of different polypeptide chains.
Which of the following is not a function of the parasympathetic division of the nervous system? - correct
answer✔✔ . Stimulation of the adrenal medulla
You place a growing seedling in an east-facing window. On which side of the plant will active auxin
accumulate? - correct answer✔✔ West side
Which of the following is NOT a characteristic of all mammalian species? - correct answer✔✔ Placenta
Suppose the lac repressor of E. coli is mutated so that it never binds to the operator. Which of the
following is true? - correct answer✔✔ The result depends on the concentration of glucose
You examine a leaf cross-section under a microscope and find many loosely packed cells. These cells
have many chloroplasts and relatively thin cell walls. These cells are: - correct answer✔✔ Parenchyma
For the biomass pyramid shown below, choose the correct statement.
secondary consumer
primary consumer producer (see question 11 on 2004 exam) - correct answer✔✔ Producers reproduce
quickly but are also consumed at a rapid rate
Which of the following would be most likely to increase competition among the members of the vole
population in a given area? - correct answer✔✔ An increase in the reproduction rate of voles
100% Correct Answers Latest
Versions 2025 Graded A+
The order of normal blood flow through the human heart is - correct answer✔✔ right atrium, right
ventricle, lungs, left atrium, left ventricle, body
Allopatric speciation refers to species formed after which type of separation: - correct answer✔✔
geographic
Which two functional groups are always found in amino acids? - correct answer✔✔ Carboxyl and amine
Movement of ions across the membrane from higher to lower concentrations through a channel protein
is an example of - correct answer✔✔ Facilitated diffusion
Which group of plants has vascular tissue but does not produce seeds?
I. Mosses
II. Ferns
III. Gymnosperms - correct answer✔✔ II
Which of the following is true for transport in xylem? - correct answer✔✔ Movement through xylem
depends mainly on transpiration
Predation is considered a _________ interaction, while Mutualism is considered a ___________
interaction. - correct answer✔✔ +/-, +/+
,Which of the following organisms is INCORRECTLY paired with its trophic level? - correct answer✔✔
Beetle - secondary consumer
Which of the following is an example of habituation? - correct answer✔✔ Hydra initially contract when
gently touched, but soon stop responding.
Suppose gene "C" is the gene for color. Its dominant allele has the effect of allowing the production of
fur color while its recessive allele interrupts color production. At another locus, there exists another
gene that influences color, at which black (B) is dominant to brown (b). What is the relationship
between these genes called? - correct answer✔✔ Epistatic
During migrations, some birds use which of the following as reference frameworks?
I. The sun
II. Constellations
III. Earth's magnetic field - correct answer✔✔ I,II, and III
Generally, there are more species per square kilometer in which of the following types of ecosystem? -
correct answer✔✔ Coral reef
RUBP is used and PGA is formed in: - correct answer✔✔ dark reaction (Calvin cycle) of photosynthesis
Which is TRUE of the dark reaction (Calvin cycle) of photosynthesis? - correct answer✔✔ It uses carbon
dioxide
In the fern life cycle, the dominant generation is the: - correct answer✔✔ diploid sporophyte
Assume a person is placed on cortisol medication, a glucocorticoid. How would you expect the rates of
ACTH and CRF hormone production to change in the person? - correct answer✔✔ ACTH production
would decrease, CRF production would increase
Carbon particles were injected into the blood of mice. In which of the following places would you most
likely find the particles? - correct answer✔✔ In monocytes of the spleen
, Kidneys provide osmoregulation for the body. Consumption of which nutrient creates the greatest need
for osmoregulation? - correct answer✔✔ Protein
During translation in prokaryotes, the ribosome binds to: - correct answer✔✔ the Shine-Dalgarno
sequence
The quaternary structure of a protein is determined by: - correct answer✔✔ .interactions between
amino acids of different polypeptide chains.
Which of the following is not a function of the parasympathetic division of the nervous system? - correct
answer✔✔ . Stimulation of the adrenal medulla
You place a growing seedling in an east-facing window. On which side of the plant will active auxin
accumulate? - correct answer✔✔ West side
Which of the following is NOT a characteristic of all mammalian species? - correct answer✔✔ Placenta
Suppose the lac repressor of E. coli is mutated so that it never binds to the operator. Which of the
following is true? - correct answer✔✔ The result depends on the concentration of glucose
You examine a leaf cross-section under a microscope and find many loosely packed cells. These cells
have many chloroplasts and relatively thin cell walls. These cells are: - correct answer✔✔ Parenchyma
For the biomass pyramid shown below, choose the correct statement.
secondary consumer
primary consumer producer (see question 11 on 2004 exam) - correct answer✔✔ Producers reproduce
quickly but are also consumed at a rapid rate
Which of the following would be most likely to increase competition among the members of the vole
population in a given area? - correct answer✔✔ An increase in the reproduction rate of voles
