BIO 212 Exam Questions and Answers Fully Solved Latest Version 2025-2026
cation exchange in soil particles, where does it happen and why - Answers soil particles are
negatively charged, so they bind to positive cations this happens on the surface of soil particles.
How does a plant take up cations from the soil - Answers plants deliver organic acids to remove
the cations from the soil particles
what does acid rain affect in terms of cation exchange - Answers the acid rain from say an
industrial revolution increases the cation exchange rate so much that nutrients leach away
which processes do plants use to get the nutrients - Answers because diffusion is only good for
short distances a plant must continually grow their root hairs which have a high SA/V ratio
which helps the uptake up nutrients.
what is the symbiotic relationship between plants and fungi - Answers plants provide sugars to
the fungi, while the fungi in return secrete enzymes that break down the sugars so that the
plants can take up nutrients/ions
undernourishment - Answers insufficient amount of "fuel" or food
malnourished - Answers lacking essential nutrients in diet
which kinds of macromolecules can be used as fuel - Answers ALL macro molecules can be
used as fuel.
definition of essential nutrient - Answers chemical needed by an organism in the form that it can
be used
how do we use nutrients - Answers they can be used as building blocks for what makes up the
organism, also in form of enzymes etc.
Nutrients that we cannot make by ourselves - Answers essential nutrients
Name categories for essential nutrients - Answers amino acids, vitamins, and some fatty acids
how many amino acids do we actually need in our diet and why? - Answers we only need 8-9
because the other ones are interconvertible by the ones we eat
why are some amino acids essential and others not? - Answers they are way too expensive to
make and much easier to eat and break down
which fatty acids are essential for us - Answers poly unsaturated omega 3 and omega 6 fatty
acids
what types of fatty acids can we make - Answers saturated FA's, omega 9's
, Vitamins why essential and what do they do for us - Answers we can't make them so they are
essential, mostly they act as co-enzymes or electron shuttling molecules (mostly organic
carbon based molecules)
why is the first process of digestion mechanical breakdown - Answers the mechanical
breakdown adds surface area for availability to enzymes, removes protective materials, and
makes it easier to move
Chemical breakdown where does it occur, what does it need, what does it do - Answers it occurs
in the digestive system, it requires a lot of water for the hydrolysis reactions, breaks polymers
down into monomers
what does water do in chemical breakdown - Answers water dilutes contents, and increases
access and provides solution for enzymes to travel in
Digestion - Answers hydrolysis of macromolecules
human digestive system step 1: tell me everything you know about what happens in the mouth -
Answers chewing which increases SA and removes protective structures
saliva dilutes and lubricates food, also adds enzymes in the form of salivary amylase and lingual
lipase
Step 2 in digestive system. where is it and what happens there - Answers the stomach, very
acidic the acidity makes it very hard for bacteria to live there. more importantly the acidity
denatures toxins that would normally be harmful to us. also pepsin in the form of pepsinogen is
released
What type of cells gives the stomach its acidity - Answers the parietal cells deliver acid to the
lumen
What type of cells gives the stomach pepsin/pepsinogen - Answers chief cells deliver the
coenzyme pepsinogen
what is the difference between pepsin and pepsinogen - Answers pepsin is the form of the
active enzyme.
how do parietal cells create and move the acid to the lumen - Answers stomach acid is HCl, the
parietal cells use carbonic anhydrase to generate the protons for the acid, the Cl- ion comes
from antiport bicarbonate (basically they flip flop) so in the parietal cell protons and chloride
ions are pumped into a canal that empties to the lumen where the proton and cl- combine to
form HCl
why are there two forms of pepsin as in the active and proenzyme form - Answers because if
pepsin was active it would eat away at the cells that made it, it can only be activated by another
pepsin molecule that occurs in the stomach
cation exchange in soil particles, where does it happen and why - Answers soil particles are
negatively charged, so they bind to positive cations this happens on the surface of soil particles.
How does a plant take up cations from the soil - Answers plants deliver organic acids to remove
the cations from the soil particles
what does acid rain affect in terms of cation exchange - Answers the acid rain from say an
industrial revolution increases the cation exchange rate so much that nutrients leach away
which processes do plants use to get the nutrients - Answers because diffusion is only good for
short distances a plant must continually grow their root hairs which have a high SA/V ratio
which helps the uptake up nutrients.
what is the symbiotic relationship between plants and fungi - Answers plants provide sugars to
the fungi, while the fungi in return secrete enzymes that break down the sugars so that the
plants can take up nutrients/ions
undernourishment - Answers insufficient amount of "fuel" or food
malnourished - Answers lacking essential nutrients in diet
which kinds of macromolecules can be used as fuel - Answers ALL macro molecules can be
used as fuel.
definition of essential nutrient - Answers chemical needed by an organism in the form that it can
be used
how do we use nutrients - Answers they can be used as building blocks for what makes up the
organism, also in form of enzymes etc.
Nutrients that we cannot make by ourselves - Answers essential nutrients
Name categories for essential nutrients - Answers amino acids, vitamins, and some fatty acids
how many amino acids do we actually need in our diet and why? - Answers we only need 8-9
because the other ones are interconvertible by the ones we eat
why are some amino acids essential and others not? - Answers they are way too expensive to
make and much easier to eat and break down
which fatty acids are essential for us - Answers poly unsaturated omega 3 and omega 6 fatty
acids
what types of fatty acids can we make - Answers saturated FA's, omega 9's
, Vitamins why essential and what do they do for us - Answers we can't make them so they are
essential, mostly they act as co-enzymes or electron shuttling molecules (mostly organic
carbon based molecules)
why is the first process of digestion mechanical breakdown - Answers the mechanical
breakdown adds surface area for availability to enzymes, removes protective materials, and
makes it easier to move
Chemical breakdown where does it occur, what does it need, what does it do - Answers it occurs
in the digestive system, it requires a lot of water for the hydrolysis reactions, breaks polymers
down into monomers
what does water do in chemical breakdown - Answers water dilutes contents, and increases
access and provides solution for enzymes to travel in
Digestion - Answers hydrolysis of macromolecules
human digestive system step 1: tell me everything you know about what happens in the mouth -
Answers chewing which increases SA and removes protective structures
saliva dilutes and lubricates food, also adds enzymes in the form of salivary amylase and lingual
lipase
Step 2 in digestive system. where is it and what happens there - Answers the stomach, very
acidic the acidity makes it very hard for bacteria to live there. more importantly the acidity
denatures toxins that would normally be harmful to us. also pepsin in the form of pepsinogen is
released
What type of cells gives the stomach its acidity - Answers the parietal cells deliver acid to the
lumen
What type of cells gives the stomach pepsin/pepsinogen - Answers chief cells deliver the
coenzyme pepsinogen
what is the difference between pepsin and pepsinogen - Answers pepsin is the form of the
active enzyme.
how do parietal cells create and move the acid to the lumen - Answers stomach acid is HCl, the
parietal cells use carbonic anhydrase to generate the protons for the acid, the Cl- ion comes
from antiport bicarbonate (basically they flip flop) so in the parietal cell protons and chloride
ions are pumped into a canal that empties to the lumen where the proton and cl- combine to
form HCl
why are there two forms of pepsin as in the active and proenzyme form - Answers because if
pepsin was active it would eat away at the cells that made it, it can only be activated by another
pepsin molecule that occurs in the stomach
