Ch. 1
A researcher discovers a single celled organism in a geothermal vent that lacks a nucleus and possesses unique membrane lipids to help it survive in this extreme climate. To which domain should this organism likely be assigned?
Archaea
What are the four major elements that a make up the human body?
O,H,N,C
A pharmaceutical scientist is designing a drug to stop a bacterium from adhering to human host cells. Which prokaryotic structure would be the most effective target for this drug?
short surface projections (pili)
If a red blood cell is placed into a hypertonic solution, what physical change will occur due to the water balance dynamics?
The cell will shrivel as water exits the cytoplasm
What evidence is used to justify that glycolysis is a process that existed billions of years ago?
It occurs in the cytosol and does not require membrane bound organelles
An agricultural scientist observes that a specific population of corn plants has become more resistant to drought over several decades of selective breeding. This intentional process is an example of which concet?
artificial selection
If a chemical containment that disrupts hydrogen boding between water molecules is introduced to a pond, what is the most immediate threat to a water strider insect residing there?
loss of surface tension causing the insect to sink
What is the plasma membrane made out of?
A phospholipid bilayer with hydrophillic heads and hydrophobic tails
A biologist observes a cell maintaining a high concentration of a certain ion inside the cell despite a much lower concentration in the surrounding extracellular fluid. Which process is primarily responsible for this observation?
Active transport
How do CAM plants such as succulents successfully conserve water while still performing photosynthesis in hot, dry climates?
They open their stomata only at night to fix carbon
When comparing a human skin cell and a leaf cell from a tree, which universal characteristic would be found in both, according to the source material?
they both use DNA as their genetic information to code for proteins
A scientist identifies a substance that contains exactly one type of atom and cannot be broken down by ordinary chemical means. If this substance is found in a quantity of less than 0.01% of human body weight but is still required for survival, how should it be classified?
A trace element
A biologist identifies a cell that contains a central vacuole, plasmodesmata, and a cell wall, but lacks centrioles. This cell is most likely from which organism?
a plant cell
A specific drug is designed to inhibit an enzyme by binding to a location other than the active site. This binding changes the enzymes shape so the substrate no longer fits. What is this mechanism called?
Non competitive inhibition
What is the specific role of NADP+ in the light reactions of photosynthesis?
It acts as a final electron acceptor, becoming reduced to NADPH
If a scientist uses the general premise "all living things require energy" to predict that a newly discovered deep sea creature must have a method of energy processing, what type of logic is being applied?
Deductive reasoning.
A patient with Phenylketonuria (PKU) suffers from seizures because they lack the enzyme phenylalanine hydroxylase. Why can this deficiency not be solved by simply increasing the concentration of other proteins?
Enzymes are highly specific for individual substrates and cannot be replaced by other proteins
In a hypothetical eukaryotic cell, a mutation prevents the golgi apparatus from functioning. What processes would be most directly interrupted.
The refinement and shipping of glycoproteins destined for the plasma membrane.
best explains why plant cells do not burst when placed in a hypotonic environment, unlike animal cells?
the cell wall exerts pressure that prevents excessive water intake
What occurs during photorespiration in C3 plants that makes it detrimental to the plant’s productivity?
Rubisco adds O2 instead of CO2 to RuBP, consuming ATP
A biologist is studying how specific protein interacts with other molecules within a mitochondria to produce energy. This researcher is operating at which level of the biological hierarchy?
Molecule
A coral reef is exposed to rising levels of atmospheric CO2, leading to ocean acidification. What is the specific chemical outcome that hinders the growth of the coral’s skeleton?
Extra H+ ions combine with carbonate ions, reducing their availability for calcification
According to the endosymbiont theory, which piece of evidence best supports the idea that mitochondria were once independent prokaryotes?
They contain their own DNA and ribosomes that resemble those found in bacteria
How does the structure of ATP allow it to drive cellular work through energy coupling?
The release of energy from its exergonic hydrolysis is used to power endergonic reactions
A researcher observes a cell that can produce ATP via oxidative phosphorylation when oxygen is present, but switches to fermentation when it is not. This organism is best classified as a:
Facultative anaerobe