Biodiversity & Ecosystem – DNA RNA
This exam is about biodiversity and ecosystem – DNA RNA.
Fermentation occurs if
carbon dioxide is not present.
glucose is not present.
carbon dioxide is present.
excess ATP is present.
oxygen is not present.- correct
The type of bond that would form from the transfer of an electron from one atom to another, shown below, is a(n) ________ bond.
The image shows an electron being transferred from one atom to another.
ionic – correct
Inside the chloroplasts, chlorophyll is found in the
thylakoid membrane.- correct
Deoxyribose is a sugar found in
Plants store their sugar in the form of
Which of the following is not a product of cellular respiration?
oxygen – correct
Amino acids are needed to build ________, just as ________ are needed to create DNA.
fatty acid; hydroxides
RNA; glucose monomers
protein; nucleotides – correct
A plant that uses CAM photosynthesis is most likely to be successful in what type of environment?
hot, dry – correct
The pH scale is a mathematical indicator of the
concentration of OH present in a solution.
total amount of all ions in a solution.
ability to dissolve in water.
ability of a solution to buffer.
concentration of H present in a solution.- correct
Some insects can stride on the surface of water because water
resists temperature changes.
has lower density when frozen.
has a high specific heat.
is a good solvent.
has surface tension.- correct
Inside a living cell, which type of bond would be the most stable?
all bonds are equally stable in a living system
covalent – correct
Which of the following organisms can perform photosynthesis?
algae – correct
Where in the cell does glycolysis occur?
cristae of mitochondrion
matrix of mitochondrion
cytoplasm – correct
Refer to the figure. Which of the following is true regarding the labeled plasma membrane?
There are four labels. The letter W represents the head portion of the layer facing towards the inside of the cell. The letter X represents the tails attached to the head facing the inside of the cell. The letter Y represents the tails attached to the heads which are facing towards the outside of the cell. The letter Z represents the heads that are facing towards the outside of the cell.
Parts W and Y are hydrophobic.
Parts X and Y are hydrophilic.
Parts W and X are hydrophilic.
Parts X and Z are hydrophobic.
Parts W and Z are hydrophilic.- correct
In the reaction 6CO2 + 6H2O → C6H12O6 + 6O2 carbon dioxide is one of the
DNA replication makes a(n) ________ copy of the DNA strand, while transcription makes a(n) ________ copy of the DNA strand.
DNA; mRNA – correct
DNA replication is called semiconservative because
the two resulting DNA molecules each have one new DNA strand and one old strand from the original DNA molecule.- correct
one of the two resulting DNA molecules is new.
the sequence of nucleotides in one strand is conserved, whereas the new DNA molecule consists of a unique sequence of nucleotides.
no extra nucleotides are incorporated into the replicated DNA molecules.
both of the resulting DNA molecules are composed of new strands of nucleotides.
While Jeff was looking under the microscope at cells in different stages of mitosis, he commented on the fact that many cells were in the same stage. If you were looking under the compound light microscope at an onion root tip, in what stage of the cell cycle would the majority of the cells be?
interphase – correct
The figure below shows a cell in the mitotic stage of
Which base is found in DNA, but not in RNA?
thymine – correct
According to Chargaff’s rules, ________ always pairs with ________, and ________ always pairs with ________.
A; C; G; T
A; T; G; C – correct
G; U; A; C
C; T; G; A
A; G; T; C
A karyotype shows chromosomes arranged by
shape, size, and complexity.
color, width, and length.
banding patterns, size, and shape.- correct
length, structure, and color.
complexity, radius, and length.
When during the cell cycle are chromosomes visible?
during mitosis – correct
only during interphase
Chromosomes are always visible.
only when they are being copied
only during the G phase
The central dogma of molecular biology states that the information contained within genes flows in which direction?
DNA to mRNA to protein – correct
mRNA to DNA to protein
DNA to tRNA to mRNA to protein
DNA to rRNA to protein
DNA to DNA to protein
________ is the study of the structure and function of cellular proteins and their interactions; ________ may be employed to use computer algorithms to aid this process.
Proteomics; comparative genomics
Comparative genomics; proteomics
Comparative genomics; bioinformatics
Proteomics; bioinformatics – correct
Most of the world’s freshwater supply is used for
bathing by humans.
drinking water for livestock.
irrigating crops.- correct
boating and recreation.
drinking water by humans.
As humans continue to use fossil fuels as a primary source of energy, the amount of carbon entering the atmosphere from fossil fuel combustion will continue to increase dramatically. What is the effect of large-scale deforestation on the carbon in the atmosphere?
Because trees produce carbon dioxide, the amount of carbon in the atmosphere will decrease with their wide-scale removal.
As trees are removed, there is more room for carbon to enter the soil directly and be used by other plants.
The large-scale removal of forests does not have any real effect on atmospheric carbon, because carbon dioxide is not stored in trees.
Because trees are a major sink for atmospheric carbon, fewer trees will result in less carbon being removed from the atmosphere for photosynthesis.- correct
What is the first step in energy flow through an ecosystem?
Producers absorb solar energy.- correct
Top-level carnivores eat the herbivores or omnivores within the ecosystem.
Decomposers break down the organic matter and make it available for the producers.
Producers absorb nutrients from the soil.
Producers are eaten by the herbivores.
Which of the following creates the least amount of soil erosion?
overgrazing by livestock
poor landscaping practices that expose the land to excess wind
use of drip irrigation systems – correct
Deforestation may contribute toward climate change because
the trees naturally trap heat near the Earth’s surface, and the loss of trees allows this heat to escape into space through the atmosphere.
it leads to salinization of the land.
the forest canopy reflects some solar radiation back into space, allowing more of it to penetrate to the Earth’s surface.
it leads to habitat loss for many forest species, which invade nearby marginal habitats, including those used by humans.
loss of trees disrupts the carbon cycle, limiting the amount that is absorbed by plants, and increasing the concentration of carbon dioxide in the atmosphere.- correct
Which of the following is not a renewable resource?
fossil fuels – correct
Desertification and deforestation are similar in that both involve
loss of wetland habitats.
lack of rainfall in an area.
loss of plant and animal life in an area.- correct
overgrowth of undesirable plants in an area.
overpopulation of an area by humans.
Conservation biology supports all of the following ethical principles except
all animals have the same rights or legal status as humans.- correct
biodiversity is desirable for the biosphere and humans.
extinction due to human actions are undesirable.
the complex interactions of ecosystems support biodiversity and are desirable.
biodiversity has value in and of itself regardless of any practical benefit to humans.
Hydropower and wind power are similar in that both are
dependent in part on fossil fuels.
sources of environmental pollution.
commonly used worldwide as power sources.
nonrenewable energy sources.
renewable energy sources.- correct
Pollution is defined as
the impact of human activity on the environment.
an undesirable alteration to the environment.- correct
an alteration in land usage.
the introduction of a new species into an environment.
the impact of animal and plant species on the environment.
In which ways does overfishing lead to decreased biodiversity?
Overfishing allows fished species to overpopulate once the larger individuals are removed from the population, which in turn depletes the species’ food sources.
It depletes food sources for aquatic mammals, which then overpopulate.
It reduces the available habitat for other species.
It depletes fish that feed on some species and serve as food sources for other species, leading to the eradication of some species and the overpopulation of others.-correct
Newer technologies allow the fishing fleet to take a larger catch while leaving larger numbers of breeding pairs, which overpopulate and degrade the environment.
Forests help to regulate the global climate by
preventing soil erosion.
absorbing carbon dioxide.- correct
The world today derives the majority of its energy from which of the following sources?
coal and oil – correct
wind and solar power
hydropower and nuclear power
Forests and other natural ecosystems, such as wetlands, exhibit the “sponge effect,” meaning that they
soak up water from runoff and rainfall, and thus accumulate pollutants.
soak up pollutants from runoff and rainfall, releasing it quickly into streams and rivers and raising their levels.
draw water away from rivers and streams, lowering their levels.
soak up water from runoff and rainfall, releasing it at a regular rate that moderates flooding of streams and rivers.- correct
soak up water from runoff and rainfall, saturating nearby ecosystems.
Which of the following terrestrial ecosystems has the highest rate of primary productivity?
tropical rainforest – correct
Which of the following methods may help conserve water by reducing the amount used for agriculture?
biological pest control
construction of dams for irrigation needs
reducing pesticide and fertilizer usage
contour with no-till farming – correct
Which of the following has not contributed to declines in the world fish catch in recent years?
use of aquaculture aquafarming – correct
depletion of fish populations through overfishing
new technologies that increase fishing efficiency
herbicide and pesticide use
Mercury can enter an aquatic food chain and collect in fish as well as people who eat fish. This is an example of which of the following processes?
biological magnification – correct
Water is a major limiting factor in which of the following biomes?
temperate grasslands – correct
Biodiversity increases the consumptive value of land, meaning that
ecosystems with higher biodiversity consume more resources than those with lower biodiversity, creating more strain on the environment.
land with lower biodiversity has many more possible uses for humans than land with higher biodiversity.
ecosystems with low biodiversity consume resources at a higher rate than those with higher biodiversity.
land that has been cleared for agriculture consumes natural resources at a slower rate and is cheaper to maintain.
more value can be derived from the more diverse products produced by ecosystems with high biodiversity relative to land that has been cleared for agriculture.-correct