Biology 235- Exam 1 Questions With 100%
Correct Answers 2024/2025
•circulatory- transport materials between cells of body
•digestive- breaks down food to be transported into body
•endocrine- coordination of body function
•immune- defend against foreign invaders
•integumentary- protect against external environment
•musculoskeletal- support and movement of body
•nervous- coordinate body function using electrical signal
•reproductive- to reproduce
•respiratory- bringing air in and out of the body
•urinary- waste removal; maintain water
List the 10 organ (body) systems and describe one function for each of them. Table 1-1
Anatomy is the study of structure while physiology is the study of what?
Physiology is the study of function and how the body part does what it does
Explain your understanding of homeostasis. Note the difference between the intracellular fluid (ICF)
and extracellular fluid (ECF). In addition to blood plasma, what constitutes the ECF?
Homeostasis is the body's tendency to maintain a certain internal environment. The body's internal
environment is extracellular fluid which contains blood plasma and interstitial fluid. extracellular fluid
is everything inside the body but outside the cell. Intracellular fluid is fluid within the cells
List 5 factors/homeostatic balances in the body need to be maintained within certain limits. Why
must these factors be maintained?
oxygen lvls, glucose lvls, temperature, pH, salt and water. these factors must be maintained because
our body can only function in a certain range.
For each of the five factors you listed, mention one body systems involved with their homeostasis.
oxygen lvl- respiratory, glucose lvls- digestive, temperature- circulatory, pH- respiratory, salt and
water- urinary
Draw an animal cell including the following structures: cell membrane, nucleus, endoplasmic
reticulum, Golgi apparatus, mitochondria and lysosomes.
DRAW ON PAPER!
In what part of the cell are chromosomes located?
the nucleus
What is the function of ribosomes? Rough endoplasmic reticulum and Golgi apparatus?
•ribosomes is where proteins are made
•rough ER is stubbed with ribosomes and responsible for assembly of proteins
•golgi apparatus- modify, transport, sorting molecules
Briefly, what is the mitochondria? Lysosomes?
•mitochondria- where ATP is made
•lysosome- responsible for waste
, Explain the difference between desmosomes and tight junctions. Fig. 3.8
DESMOSOMES anchor cells to each other and TIGHT JUNCTION anchor cells and prevent fluid and
molecules from moving between cells
What type of molecules can pass freely through the lipid-bilayer part of the cell membrane? What
properties determine if a molecule will pass through? Fig. 5.7
hydrophobic molecules can pass freely. concentration gradient determines if the molecule will pass
freely
Explain what a concentration gradient is. Can molecules flow up their concentration gradient? Explain.
Concentration gradient is the difference in concentration of a substance in two places. One side is
high and the other is low in concentration. Molecules can flow up their concentration gradient.
Flowing against it requires active transport because energy is needed for the substance that is low in
one place to move on to the higher concentration side.
Besides structural, list 3 other functions of membrane proteins. Fig. 5.8
can be catalyst, receptors, and transporters
Explain the difference between facilitative diffusion and simple diffusion.
facilitative diffusion requires protein transporter while simple diffusion doesn't
Explain the difference between active and passive transport.
active transport requires energy while passive transport requires no energy
Explain the difference between protein channels and protein carriers. Fig. 5.10
Protein channels are gated and chooses which molecules to let through. Protein carriers are like
revolving doors. The door only opens to one side at a time.
What if the difference between a uniport, symport and antiport?
•uniport moves one molecule
•symport moves two molecules in the same direction
•antiport moves two molecules at a time in the opposite direction
Explain the mechanism of the Na-K+ ATPase (Fig. 5.15) and note at which step ATP is used.
Na+ binds to the site. ATP comes in and phosphorylates with protein this causes the transporter to
switch to the other side. Na+ is then released. K+ binds to the site causing causing the phosphate to
be released. when phosphate is released the transporter flips back to the other side and K+ released
from the site again. The process continues. ATP is used in the second step where the protein gets
phosphorylated
Explain how glucose gets transported from one side of the cell to another. Fig. 5.21 Make sure to
explain the roles of each of the three membrane proteins.
Glucose and sodium enter the cell through a symport. Glucose comes in from low to high-active and
facilitated and goes into the extracellular fluid. Sodium is present so that the energy from sodium
coming in allows glucose can come in. Sodium comes in from high to low-passive and facilitated and
goes out of the cell. ATP is needed to keep the sodium concentration low.
Correct Answers 2024/2025
•circulatory- transport materials between cells of body
•digestive- breaks down food to be transported into body
•endocrine- coordination of body function
•immune- defend against foreign invaders
•integumentary- protect against external environment
•musculoskeletal- support and movement of body
•nervous- coordinate body function using electrical signal
•reproductive- to reproduce
•respiratory- bringing air in and out of the body
•urinary- waste removal; maintain water
List the 10 organ (body) systems and describe one function for each of them. Table 1-1
Anatomy is the study of structure while physiology is the study of what?
Physiology is the study of function and how the body part does what it does
Explain your understanding of homeostasis. Note the difference between the intracellular fluid (ICF)
and extracellular fluid (ECF). In addition to blood plasma, what constitutes the ECF?
Homeostasis is the body's tendency to maintain a certain internal environment. The body's internal
environment is extracellular fluid which contains blood plasma and interstitial fluid. extracellular fluid
is everything inside the body but outside the cell. Intracellular fluid is fluid within the cells
List 5 factors/homeostatic balances in the body need to be maintained within certain limits. Why
must these factors be maintained?
oxygen lvls, glucose lvls, temperature, pH, salt and water. these factors must be maintained because
our body can only function in a certain range.
For each of the five factors you listed, mention one body systems involved with their homeostasis.
oxygen lvl- respiratory, glucose lvls- digestive, temperature- circulatory, pH- respiratory, salt and
water- urinary
Draw an animal cell including the following structures: cell membrane, nucleus, endoplasmic
reticulum, Golgi apparatus, mitochondria and lysosomes.
DRAW ON PAPER!
In what part of the cell are chromosomes located?
the nucleus
What is the function of ribosomes? Rough endoplasmic reticulum and Golgi apparatus?
•ribosomes is where proteins are made
•rough ER is stubbed with ribosomes and responsible for assembly of proteins
•golgi apparatus- modify, transport, sorting molecules
Briefly, what is the mitochondria? Lysosomes?
•mitochondria- where ATP is made
•lysosome- responsible for waste
, Explain the difference between desmosomes and tight junctions. Fig. 3.8
DESMOSOMES anchor cells to each other and TIGHT JUNCTION anchor cells and prevent fluid and
molecules from moving between cells
What type of molecules can pass freely through the lipid-bilayer part of the cell membrane? What
properties determine if a molecule will pass through? Fig. 5.7
hydrophobic molecules can pass freely. concentration gradient determines if the molecule will pass
freely
Explain what a concentration gradient is. Can molecules flow up their concentration gradient? Explain.
Concentration gradient is the difference in concentration of a substance in two places. One side is
high and the other is low in concentration. Molecules can flow up their concentration gradient.
Flowing against it requires active transport because energy is needed for the substance that is low in
one place to move on to the higher concentration side.
Besides structural, list 3 other functions of membrane proteins. Fig. 5.8
can be catalyst, receptors, and transporters
Explain the difference between facilitative diffusion and simple diffusion.
facilitative diffusion requires protein transporter while simple diffusion doesn't
Explain the difference between active and passive transport.
active transport requires energy while passive transport requires no energy
Explain the difference between protein channels and protein carriers. Fig. 5.10
Protein channels are gated and chooses which molecules to let through. Protein carriers are like
revolving doors. The door only opens to one side at a time.
What if the difference between a uniport, symport and antiport?
•uniport moves one molecule
•symport moves two molecules in the same direction
•antiport moves two molecules at a time in the opposite direction
Explain the mechanism of the Na-K+ ATPase (Fig. 5.15) and note at which step ATP is used.
Na+ binds to the site. ATP comes in and phosphorylates with protein this causes the transporter to
switch to the other side. Na+ is then released. K+ binds to the site causing causing the phosphate to
be released. when phosphate is released the transporter flips back to the other side and K+ released
from the site again. The process continues. ATP is used in the second step where the protein gets
phosphorylated
Explain how glucose gets transported from one side of the cell to another. Fig. 5.21 Make sure to
explain the roles of each of the three membrane proteins.
Glucose and sodium enter the cell through a symport. Glucose comes in from low to high-active and
facilitated and goes into the extracellular fluid. Sodium is present so that the energy from sodium
coming in allows glucose can come in. Sodium comes in from high to low-passive and facilitated and
goes out of the cell. ATP is needed to keep the sodium concentration low.
