©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
HCS 212 Exam 1 Study Questions and
Answers
Chapter 2 - Ans:✔✔-Chapter 2
Extracellular fluid - Ans:✔✔-Body fluids located outside of cells; includes plasma and interstitial fluid
What can the cytoplasm be divided into? - Ans:✔✔-Cytosol and organelles
Plasma membrane - Ans:✔✔-• A cell membrane; also called a *plasmalemma* or cell membrane or
phospholipid bilayer
• Has four important functions:
> 1) Physical isolation
> 2) Regulation of exchange with the environment
> 3) Sensitivity
> 4) Cell-to-cell communication, adhesion, and structural support
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• Selectively permeable
What is the plasma membrane composed of? - Ans:✔✔-Phospholipids, proteins, glycolipids, and sterols
such as cholesterols
What are the two general types of membrane protein called? - Ans:✔✔-• 1) Peripheral proteins --
>Attached to either the inner or outer membrane surface
• 2) Integral proteins (transmembrane proteins) --> Embedded in the membrane; most proteins are quite
ling and folded, and, therefore, span the entire width of the membrane one or more times. Some
integral proteins form channels that let water molecules, ions, and small water-soluble substances into
or our of the cell
Glycocalyx - Ans:✔✔-The external surface of a plasma membrane that is important for cell-to-cell
communication; viscous, superficial coating that is formed by the carbohydrate (glyco-) components of
the glycolopids and glycoproteins that extend away from the outer surface of the plasma membrane
Sterols - Ans:✔✔-• Stabilize the membrane structure and maintain its fluidity
• Cholesterol is the most common sterol
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What are the passive processes of transport? - Ans:✔✔-• 1) Diffusion --> Passive molecular movement
from an area of relatively *high concentration to* an area of relatively *low concentration*
• 2) Osmosis --> The movement of *water* across a semipermeable membrane *toward* a solution
containing a relatively *high solute concentration*
• 3) Facilitated diffusion --> Passive movement of a substance across a plasma membrane via a protein
carrier
What are the active processes of transport? - Ans:✔✔-• 1) Active transport --> The ATP-dependent
absorption or excretion of solutes across a plasma membrane
• 2) Endocytosis --> The movement of relatively large volumes of extra
• 3) Exocytosis --> The ejection of cytoplasmic materials by fusion of a membranous vesicle with the
plasma membrane
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, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
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Microvilli - Ans:✔✔-• Small, finger-shaped projections of the plasma membrane that absorb materials
from the extracellular fluid
• Promote absorption by increasing the surface area exposed to the extracellular environment. A
network of microfilaments stiffens each microvillus and anchors it to the terminal web, a dense
supporting network within the underlying cytoskeleton
• Interactions between the microfilaments and the cytoskeleton produce a waving or bending action
• Movement of the microvilli circulate fluids close to the plasma membrane, bringing dissolved
substances into contact with receptors on the membrane surface
Cytoskeleton - Ans:✔✔-The cell's internal framework of filaments and fibers; A *network of
microtubules, microfilaments, intermediate filaments, and thick filaments * in the cytoplasm
Cytoplasm - Ans:✔✔-The material between the plasma membrane and the nuclear membrane
In a cell, what percentage of weight does protein contribute? - Ans:✔✔-15 - 30%
Page 4/94
FIRST PUBLISH OCTOBER 2024
HCS 212 Exam 1 Study Questions and
Answers
Chapter 2 - Ans:✔✔-Chapter 2
Extracellular fluid - Ans:✔✔-Body fluids located outside of cells; includes plasma and interstitial fluid
What can the cytoplasm be divided into? - Ans:✔✔-Cytosol and organelles
Plasma membrane - Ans:✔✔-• A cell membrane; also called a *plasmalemma* or cell membrane or
phospholipid bilayer
• Has four important functions:
> 1) Physical isolation
> 2) Regulation of exchange with the environment
> 3) Sensitivity
> 4) Cell-to-cell communication, adhesion, and structural support
Page 1/94
, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
• Selectively permeable
What is the plasma membrane composed of? - Ans:✔✔-Phospholipids, proteins, glycolipids, and sterols
such as cholesterols
What are the two general types of membrane protein called? - Ans:✔✔-• 1) Peripheral proteins --
>Attached to either the inner or outer membrane surface
• 2) Integral proteins (transmembrane proteins) --> Embedded in the membrane; most proteins are quite
ling and folded, and, therefore, span the entire width of the membrane one or more times. Some
integral proteins form channels that let water molecules, ions, and small water-soluble substances into
or our of the cell
Glycocalyx - Ans:✔✔-The external surface of a plasma membrane that is important for cell-to-cell
communication; viscous, superficial coating that is formed by the carbohydrate (glyco-) components of
the glycolopids and glycoproteins that extend away from the outer surface of the plasma membrane
Sterols - Ans:✔✔-• Stabilize the membrane structure and maintain its fluidity
• Cholesterol is the most common sterol
Page 2/94
, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
What are the passive processes of transport? - Ans:✔✔-• 1) Diffusion --> Passive molecular movement
from an area of relatively *high concentration to* an area of relatively *low concentration*
• 2) Osmosis --> The movement of *water* across a semipermeable membrane *toward* a solution
containing a relatively *high solute concentration*
• 3) Facilitated diffusion --> Passive movement of a substance across a plasma membrane via a protein
carrier
What are the active processes of transport? - Ans:✔✔-• 1) Active transport --> The ATP-dependent
absorption or excretion of solutes across a plasma membrane
• 2) Endocytosis --> The movement of relatively large volumes of extra
• 3) Exocytosis --> The ejection of cytoplasmic materials by fusion of a membranous vesicle with the
plasma membrane
Page 3/94
, ©GRACEAMELIA 2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
Microvilli - Ans:✔✔-• Small, finger-shaped projections of the plasma membrane that absorb materials
from the extracellular fluid
• Promote absorption by increasing the surface area exposed to the extracellular environment. A
network of microfilaments stiffens each microvillus and anchors it to the terminal web, a dense
supporting network within the underlying cytoskeleton
• Interactions between the microfilaments and the cytoskeleton produce a waving or bending action
• Movement of the microvilli circulate fluids close to the plasma membrane, bringing dissolved
substances into contact with receptors on the membrane surface
Cytoskeleton - Ans:✔✔-The cell's internal framework of filaments and fibers; A *network of
microtubules, microfilaments, intermediate filaments, and thick filaments * in the cytoplasm
Cytoplasm - Ans:✔✔-The material between the plasma membrane and the nuclear membrane
In a cell, what percentage of weight does protein contribute? - Ans:✔✔-15 - 30%
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