Cell Membrane
Cell Transport & Tonicity
Cell Systems
Lysosome & Cytoskeleton
Myth or fact?
100
The functions of the cell membrane:
-Provides support and protection
-Is selectively permeable
-Cell recognition
-Maintains optimal conditions inside the cell, homeostasis
100
What are the two main types of cell transport? Which one requires ATP?
Active and passive transport. Active transport requires ATP.
100
The endomembrane system has a molecular zip code called
ER signal sequence.
100
What cytoskeleton filament helps with Keratin and Nuclear Lamins?
Intermediate Filament
100
Cracking knuckles causes arthritis: Myth or Fact?
Myth!
The popping sound comes from gas bubbles in synovial fluid.
200
Draw and label a phospholipid. Explain what amphipathic is.
Contains a hydrophilic (polar) head, a hydrophobic (non-polar) fatty acid tail, a ester linkage. Amphipathic means to contain both hydrophilic and hydrophobic regions.
200
Channel Protein, Carrier Protein, Gated channels are what type of cell transport?
Facilitated Diffusion, proteins are assisted in diffusion.
200
If a protein doesn't contain the Nuclear Localization Sequence (NLS) what happens to the protein?
The protein's tail cannot enter the nucleus and stays in the cytosol with its core.
200
The three recycling pathways are:
-Receptor mediated endocytosis
- Phagocytosis
- Autophagy
200
Octopuses Have Three Hearts: Myth or Fact?
Fact!
Two hearts pump blood to the gills, one pumps it to the rest of the body. The main heart can stop when swimming.
300
Explain what factors affect membrane permeability.
-Size & Ion charge: Small molecules= higher permeability, large molecules= lower permeability, highly charged molecules have low permeability
-Unsaturated vs saturated: unsatur= short hydrocarbon trails= higher permeability, satur= long hydrocarbon tails= lower permeability
-Cholesterol: more cholesterol= less permeability
-Temperature: Colder temp= slow movement, hotter temp= fast movement
300
A cell contains 5% solute, while the surrounding solution contains 15% solute.
Is the surrounding solution hypertonic, hypotonic, or isotonic relative to the cell? Which direction will water move? What will happen to the cell
The surrounding solution is hypertonic, water moves out of the cell, the cell shrinks.
300
Oh no... Your group loses -300 pts.
Every other group gets +300pts.
300
Draw a Microtubule and identify:
monomer, overall structure, one function
Helps with structural framework for organelles like ER and Golgi.
300
Freebie!
(every group gets 300pt)
400
Which of the following would cross the phospholipid bilayer most easily?
O₂, Glucose, or Na⁺
Explain.
O₂ will cross easily because it is small and nonpolar/hydrophobic similar to the makeup of the membrane's bilayer. Glucose is a large, uncharged, polar sugar. Na⁺ is an ion that will need help getting through the membrane bilayer.
400
A cell is placed into an unknown solution. Nine minutes later, the cell expanded. You don't know either solute concentration. What can you conclude?
The solution was hypotonic relative to the cell, causing net water movement into the cell.
400
Put these in the correct order for a secreted protein (Endomembrane system):
-Golgi
-Plasma membrane
-Secretory vesicle
-Rough ER
Rough ER → Golgi → secretory vesicle → plasma membrane.
400
A damaged mitochondrion becomes surrounded by an internal membrane and is eventually delivered to a lysosome. Identify the pathway
Autophagy
400
Orangutans share over 97% of their DNA with humans: Myth or Fact?
Fact!
They are an intelligent species that excel in tool use, problem-solving, and social learning in their environments.
500
Membrane A contains more unsaturated fatty acids and is in a hot environment. Membrane B contains more saturated fatty acids and is in a cold environment. Which membrane has greater fluidity? Explain your reasoning.
Membrane A has a greater fluidity than membrane B. Unsaturated fatty acids have short tails that have cis double bonds, preventing phospholipids from packing tightly together. Hotter temperatures lead to more fluidity.
500
You just ate a bag of sea salt (NaCl) potato chips. Your chips were digested in your stomach, and the Na+ was absorbed into the bloodstream through the small intestine. Na+ is needed to maintain the membrane potential in the cell. What kind of cell transport is used? Explain?
Active transport. Na⁺ is a charged ion and cannot enter the cell's membrane passively; it requires ATP to enter the cell against its concentration gradient.
500
Draw the Pulse Chase experiment graph. At what time do you find the most labeled proteins?
In the rough ER at 0min.
500
A hydrolytic enzyme lacks mannose-6-phosphate (M6P), what happens to that protein? Why is it important for this protein to have M6P?
Mannose-6- phosphate is the shipping tag for digestive enzymes; it directs them into the lysosomes. If digestive enzymes lack M6P they can't travel to the lysosomes and help with breaking down material.
500
Your Brain Has More Connections Than Stars in the Galaxy: True or False?
True!
The human brain has about 100 billion neurons and over 100 trillion synaptic connections. The Milky Way galaxy has about 100–400 billion stars.