PROKARYOTE VS. EUKARYOTE
What is the main difference between a prokaryotic cell and a eukaryotic cell?
Eukaryotic cells have a nucleus that holds their DNA, while prokaryotic cells do not.
Which organelle is like the "brain" or "control center" of the cell, and what does it store?
The nucleus is the control center. It stores the cell's genetic material, or DNA.
The cell membrane is picky about what it lets in and out. What term describes a membrane that only allows certain things to pass through?
Selectively permeable (or semi-permeable).
If you soak a gummy bear in plain, pure water overnight, what happens to the gummy bear and why?
The gummy bear will swell up and get bigger. Water moves from the area of high water concentration (the pure water) into the gummy bear (which has lower water concentration due to all its sugar) through the process of osmosis.
Which process uses sunlight, water, and carbon dioxide to make food (glucose) and oxygen?
Photosynthesis
Which type of cell is usually larger and more complex?
Eukaryotic cells are typically larger and have more specialized internal parts (organelles) than prokaryotic cells.
Plant cells can make their own food using sunlight. Which organelle is responsible for this process (photosynthesis), and is it found in animal cells?
The chloroplast performs photosynthesis. It is found in plant cells but generally not in animal cells.
Molecules naturally move from an area where there are a lot of them to an area where there are fewer of them, like a scent spreading across a room. What is this movement called?
Diffusion
Why does gargling with salt water help a swollen, sore throat feel better?
The high concentration of salt in the water creates an environment that pulls the excess water out of the swollen throat cells by osmosis. This loss of water causes the cells to shrink and the swelling to go down.
Which organelle is the location where cellular respiration happens and energy is released from food?
The mitochondria are where cellular respiration takes place.
Are bacteria examples of prokaryotic or eukaryotic cells?
Bacteria are prokaryotic cells.
Which organelle is known as the "powerhouse" of the cell because it breaks down sugar to release energy for the cell to use?
The mitochondria (or mitochondrion) produce energy for the cell to function.
Does the cell need to use extra energy (like ATP from the mitochondria) to move materials during passive transport, or does it happen automatically?
It happens automatically (no energy required) because the molecules are moving "down" their concentration gradient.
Plants absorb water from the soil using their roots. Is the concentration of water higher in the soil or inside the plant's root cells?
The concentration of water is higher in the soil. Water moves from the soil, through the root cell membranes, and into the plant to achieve balance.
Photosynthesis and cellular respiration are opposites. If plants release oxygen during photosynthesis, what gas do both plants and animals release during cellular respiration?
They release carbon dioxide (CO2).
Name one part that is found in both prokaryotic and eukaryotic cells.
Both types of cells have a cell membrane (outer boundary), cytoplasm (jelly-like filling), and ribosomes (tiny protein makers).
Imagine a cell as a factory. Which organelle is like the "packaging and shipping center" that modifies, sorts, and packages proteins and other materials?
The Golgi apparatus (or Golgi complex) packages and distributes materials.
What specific type of passive transport involves only the movement of water molecules across the cell membrane?
Osmosis
Imagine a red blood cell with a 0.9% salt concentration inside it. If you put that cell into a 10% salt solution (very salty water), what happens to the cell?
The red blood cell will shrink or shrivel up. The water inside the cell moves out into the highly concentrated saltwater solution to try to even out the concentration.
Plants can do both photosynthesis and cellular respiration. When do they perform photosynthesis, and when do they perform cellular respiration?
Plants perform photosynthesis only during the day (when they have sunlight). They perform cellular respiration all the time, both day and night.
Why do eukaryotic cells have an advantage by having organelles (like mitochondria or a nucleus)?
Organelles allow the cell to perform different jobs at the same time in separate, organized areas, making the cell much more efficient
Both plant and animal cells have an outer boundary that controls what enters and leaves the cell. What is this boundary called?
This boundary is the cell membrane. (Note: Plant cells have an additional, rigid cell wall outside the membrane for extra support).
If a cell needs to move a substance from an area where there is very little of it to an area where there is a lot of it (going against the flow), what type of transport must it use, and does it require energy?
It must use active transport, and yes, it requires energy (ATP) to power special protein pumps.
Which term describes a solution that has the exact same concentration of water and solutes as the inside of a cell, causing no net movement of water and keeping the cell's volume stable?
An isotonic solution. (For example, normal saline used in hospitals is an isotonic solution compatible with human blood cells)
Think about the big picture: The products of one reaction are the reactants for the other, forming a cycle. What four substances are recycled back and forth between the two processes?
Glucose (sugar), oxygen, carbon dioxide, and water are continuously recycled between photosynthesis and cellular respiration.