BIOL 2401 Exam 1 Larson Questions | 2026/2027 | Answers
Correct | With Complete Solutions
Phagocytosis
• "cell swallowing" of foreign particles or cell debris
• Examples:Macrophages, white blood cells
Receptor-mediated endocytosis
• substances bind to specific receptor
proteins.
• Example: Uptake of enzymes, iron,
insulin
Exocytosis
- Requires ATP to transport large substances out of the cell.
- Examples: Hormone secretion, neurotransmitter release, mucus
secretion, ejection of wastes
A red blood cell placed into a container of distilled water
will________ water via _________.
gain; osmosis
The sodium-potassium pump __________.
pumps Na + out of and K + into the cell
Which of the following is not an example of simple diffusion?
A. Gas exchange in our lungs
B. A dissolving sugar cube
C. Popcorn odor permeating the room
,D. A white blood cell engulfing a
bacterium
A white blood cell engulfing a
bacterium
Membrane Potential
• separation of opposite charges across the plasma membrane
• potential energy that is measured in voltage
• resting membrane potential (RMP): resting cell (-50 to -100
mV)
sodium-potassium pump steps
1. Resting cell: Low [Na+] and high [K+] inside cell
2. The Na+ -K+ pump uses ATP to continuously transport 3
Na+ OUT of the cell and carries 2 K+ INTO the cell.
3. Because more positive charge is moving out of the cell (3)
than into the cell (2), the inside of the cell becomes
negatively charged.
4. Electrochemical gradient (negative charge inside cell) begins
to attract the positively charged K+ back into cell.
(The membrane is slightly more permeable to K+)
5. RMP is established at the point where the electrical gradient
balances the K+ concentration gradient
6. A steady state is maintained because the rate of active
transport is equal to and depends on the rate of K+ diffusion into
cell
embryonic germ layers
ectoderm, mesoderm, endoderm
,Tissue categories
epithelial, connective, muscular, nervous
epithelium
all three germ layers
endoderm
inner lining of digestive sysytem
ectoderm
nervous tissue
mesoderm
muscle connective tissue
cutaneous membrane
skin; dry membrane, exposed to air
mucous membrane
lines a body cavities that opens directly to the outside; traps
particles, lubricates; small intestine, mucosa of nasal cavity,
mucosa of mouth, esophagus lining, mucosa of lung bronchi
serous membrane
lines a body cavity that dose not open directly to the outside;
prevents friction, covers internal organs and body cavities;
parietal pleura, visceral pleura
epithelial tissue characteristics
, Cells fit closely together and often form sheets
The apical surface is the free surface of the tissue
The lower surface of the epithelium rests on a basement
membrane
Avascular (no blood supply)
Regenerate easily if well nourished
basal surface
deep surface; selective filter
basement membrane
connective tissue supports epithelial tissue,, resists stretching &
tearing
avascular
does not contain blood vessels; nourishment comes from deep
connective tissue layers
high tissue regeneration
mitotically active; replace cells damanaged by friction, acids,
etc.
simple epithelia
one layer of cells
stratified epithelia
two or more layers of cells
pseudostratified epithelia
one layer of cells but looks like mupliple layers
Correct | With Complete Solutions
Phagocytosis
• "cell swallowing" of foreign particles or cell debris
• Examples:Macrophages, white blood cells
Receptor-mediated endocytosis
• substances bind to specific receptor
proteins.
• Example: Uptake of enzymes, iron,
insulin
Exocytosis
- Requires ATP to transport large substances out of the cell.
- Examples: Hormone secretion, neurotransmitter release, mucus
secretion, ejection of wastes
A red blood cell placed into a container of distilled water
will________ water via _________.
gain; osmosis
The sodium-potassium pump __________.
pumps Na + out of and K + into the cell
Which of the following is not an example of simple diffusion?
A. Gas exchange in our lungs
B. A dissolving sugar cube
C. Popcorn odor permeating the room
,D. A white blood cell engulfing a
bacterium
A white blood cell engulfing a
bacterium
Membrane Potential
• separation of opposite charges across the plasma membrane
• potential energy that is measured in voltage
• resting membrane potential (RMP): resting cell (-50 to -100
mV)
sodium-potassium pump steps
1. Resting cell: Low [Na+] and high [K+] inside cell
2. The Na+ -K+ pump uses ATP to continuously transport 3
Na+ OUT of the cell and carries 2 K+ INTO the cell.
3. Because more positive charge is moving out of the cell (3)
than into the cell (2), the inside of the cell becomes
negatively charged.
4. Electrochemical gradient (negative charge inside cell) begins
to attract the positively charged K+ back into cell.
(The membrane is slightly more permeable to K+)
5. RMP is established at the point where the electrical gradient
balances the K+ concentration gradient
6. A steady state is maintained because the rate of active
transport is equal to and depends on the rate of K+ diffusion into
cell
embryonic germ layers
ectoderm, mesoderm, endoderm
,Tissue categories
epithelial, connective, muscular, nervous
epithelium
all three germ layers
endoderm
inner lining of digestive sysytem
ectoderm
nervous tissue
mesoderm
muscle connective tissue
cutaneous membrane
skin; dry membrane, exposed to air
mucous membrane
lines a body cavities that opens directly to the outside; traps
particles, lubricates; small intestine, mucosa of nasal cavity,
mucosa of mouth, esophagus lining, mucosa of lung bronchi
serous membrane
lines a body cavity that dose not open directly to the outside;
prevents friction, covers internal organs and body cavities;
parietal pleura, visceral pleura
epithelial tissue characteristics
, Cells fit closely together and often form sheets
The apical surface is the free surface of the tissue
The lower surface of the epithelium rests on a basement
membrane
Avascular (no blood supply)
Regenerate easily if well nourished
basal surface
deep surface; selective filter
basement membrane
connective tissue supports epithelial tissue,, resists stretching &
tearing
avascular
does not contain blood vessels; nourishment comes from deep
connective tissue layers
high tissue regeneration
mitotically active; replace cells damanaged by friction, acids,
etc.
simple epithelia
one layer of cells
stratified epithelia
two or more layers of cells
pseudostratified epithelia
one layer of cells but looks like mupliple layers
