Rio Bio 156 Exam 1 Questions and Answers GRADED to pass!!
2025/2026.
Passive transport mechanism in which a solute follows its concentration gradient across a
membrane by moving through a transport protein.
Distinguish between exocytosis and endocytosis.
endocytosis: Process by which a cell takes in a small amount of extracellular fluid (and its
contents) by the ballooning inward of the plasma membrane.
exocytosis: Process by which a cell expels a vesicle's contents to extracellular fluid.
Describe an amoeba feeding by phagocytosis.
a type of receptor-mediated endocytosis in which motile cells engulf microorganisms, cellular
debris, or other large particles.
Describe the basic events of glycolysis.
a series of reactions beginning with the breakdown of a glucose molecule to pyruvate. A small
amount (two molecules) of ATP is produced directly at this time. Electrons are carried to the
electron transport chain by NADH, a special coenzyme electron carrier. Glycolysis takes place in
the cytoplasm of the cell.
Describe the basic events of Krebs Cycle
The Krebs cycle, or Citric Acid Cycle, is the name given to the set of reactions in which pyruvate
is broken down by enzymes to carbon dioxide. Again, a small amount of ATP (two molecules) is
made directly during these events. Once again, electrons are carried to the electron transport
chain by NAD+. Another electron carrier, FAD, is also active here. The Krebs cycle takes place
in the matrix of the mitochondria - the area outside of the cristae.
aerobic
Involving or occurring in the presence of oxygen.
anaerobic
Occurring in the absence of oxygen.
aerobic respiration
Oxygen-requiring metabolic pathway that breaks down sugars to produce ATP.
aerobic respiration can be dangerous
When an oxygen molecule (O2) accepts electrons from an electron transfer chain, it dissociates
into oxygen atoms. Most of the atoms immediately combine with hydrogen ions and end up in
water molecules. however, an oxygen atom escapes this final reaction. The atom has an unpaired
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, electron, so it is a free radical. mitochondria cannot detoxify free radicals, so they rely on
antioxidant enzymes and vitamins in the cell's cytoplasm to do it for them.
oxidative stress
Free radicals accumulate and destroy first the function of mitochondria, then the cell. The
resulting tissue damage
by mitochondrial malfunction is also involved in
many other illnesses, including cancer, hypertension, Alzheimer's and Parkinson's diseases, and
even aging.
symptoms: mild to major progressive neurological deficits, blindness, deafness, diabetes, strokes,
seizures, gastrointestinal malfunction, and disabling muscle weakness.
List features that distinguish living organisms from nonliving matter.
1. Cellular basis - All living things consist of one or more cells
2. Requirement for energy and nutrients - Life is sustained by ongoing inputs of energy and
nutrients
3. Homeostasis - Living things sense and respond to change
4. DNA is hereditary material - Genetic information in the form of DNA is passed to offspring
Describe the levels of organization in the living world.
Atoms → cells → tissues → organs → organ systems → organism → population → community
→ ecosystem → the biosphere
List the three domains of life and distinguish between each domain.
Prokaryotes are bacteria and archaea.
Domain Bacteria: unicellular no nucleus
Domain Archaea: unicellular no nucleus but closer to eukarya
Domain Eukarya: have nucleus
List four kingdoms within the domain Eukarya and distinguish between them.
1. Fungi can be single or multicellular but digest food outside their body.
2. Plants are multicellular and are photosynthetic.
3. Animals are multicellular and eat other organisms for nutrients.
4. Protists are the unicellular organisms that have a nucleus but do not fit any other category.
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2025/2026.
Passive transport mechanism in which a solute follows its concentration gradient across a
membrane by moving through a transport protein.
Distinguish between exocytosis and endocytosis.
endocytosis: Process by which a cell takes in a small amount of extracellular fluid (and its
contents) by the ballooning inward of the plasma membrane.
exocytosis: Process by which a cell expels a vesicle's contents to extracellular fluid.
Describe an amoeba feeding by phagocytosis.
a type of receptor-mediated endocytosis in which motile cells engulf microorganisms, cellular
debris, or other large particles.
Describe the basic events of glycolysis.
a series of reactions beginning with the breakdown of a glucose molecule to pyruvate. A small
amount (two molecules) of ATP is produced directly at this time. Electrons are carried to the
electron transport chain by NADH, a special coenzyme electron carrier. Glycolysis takes place in
the cytoplasm of the cell.
Describe the basic events of Krebs Cycle
The Krebs cycle, or Citric Acid Cycle, is the name given to the set of reactions in which pyruvate
is broken down by enzymes to carbon dioxide. Again, a small amount of ATP (two molecules) is
made directly during these events. Once again, electrons are carried to the electron transport
chain by NAD+. Another electron carrier, FAD, is also active here. The Krebs cycle takes place
in the matrix of the mitochondria - the area outside of the cristae.
aerobic
Involving or occurring in the presence of oxygen.
anaerobic
Occurring in the absence of oxygen.
aerobic respiration
Oxygen-requiring metabolic pathway that breaks down sugars to produce ATP.
aerobic respiration can be dangerous
When an oxygen molecule (O2) accepts electrons from an electron transfer chain, it dissociates
into oxygen atoms. Most of the atoms immediately combine with hydrogen ions and end up in
water molecules. however, an oxygen atom escapes this final reaction. The atom has an unpaired
1|Page
, electron, so it is a free radical. mitochondria cannot detoxify free radicals, so they rely on
antioxidant enzymes and vitamins in the cell's cytoplasm to do it for them.
oxidative stress
Free radicals accumulate and destroy first the function of mitochondria, then the cell. The
resulting tissue damage
by mitochondrial malfunction is also involved in
many other illnesses, including cancer, hypertension, Alzheimer's and Parkinson's diseases, and
even aging.
symptoms: mild to major progressive neurological deficits, blindness, deafness, diabetes, strokes,
seizures, gastrointestinal malfunction, and disabling muscle weakness.
List features that distinguish living organisms from nonliving matter.
1. Cellular basis - All living things consist of one or more cells
2. Requirement for energy and nutrients - Life is sustained by ongoing inputs of energy and
nutrients
3. Homeostasis - Living things sense and respond to change
4. DNA is hereditary material - Genetic information in the form of DNA is passed to offspring
Describe the levels of organization in the living world.
Atoms → cells → tissues → organs → organ systems → organism → population → community
→ ecosystem → the biosphere
List the three domains of life and distinguish between each domain.
Prokaryotes are bacteria and archaea.
Domain Bacteria: unicellular no nucleus
Domain Archaea: unicellular no nucleus but closer to eukarya
Domain Eukarya: have nucleus
List four kingdoms within the domain Eukarya and distinguish between them.
1. Fungi can be single or multicellular but digest food outside their body.
2. Plants are multicellular and are photosynthetic.
3. Animals are multicellular and eat other organisms for nutrients.
4. Protists are the unicellular organisms that have a nucleus but do not fit any other category.
2|Page
