Traffic Control: Cell Addition
What is the main difference between passive transport and active transport?
Passive transport does not require energy; active transport does.
Osmosis is the movement of _______ from high to low concentration.
Water.
What is homeostasis?
Maintaining a stable internal environment.
What organelle performs photosynthesis?
The Chloroplast.
What molecule stores and releases energy for the cell?
ATP
Name two types of passive transport.
Simple diffusion, facilitated diffusion, or osmosis (any two).
A cell with 95% water is placed in a solution with 80% water. Will water move in or out?
Out of the cell (hypertonic solution).
Which type of feedback loop increases a change or pushes a process further?
Positive feedback.
Write the basic formula for photosynthesis (words only).
Carbon dioxide + water + sunlight → glucose + oxygen.
Where does cellular respiration mainly occur?
The mitochondria.
In receptor-mediated endocytosis, what role do receptors play?
They bind to specific target molecules to bring them into the cell.
Describe a hypotonic solution and what happens to a cell placed in one.
More water outside than inside; water moves into the cell; the cell swells.
Name the 3 parts of a feedback loop and their roles.
Receptor: detects change
Control center: decides response
Effector: carries out the response
What is the main purpose of the light-dependent reactions?
Capture sunlight energy to produce ATP and NADPH.
Compare aerobic and anaerobic respiration.
Aerobic uses oxygen and produces much more ATP; anaerobic does not use oxygen and produces less ATP.
A cell uses energy to engulf large solid particles such as bacteria. What process is this? (BE SPECIFIC)
Phagocytosis, a form of endocytosis.
A beaker has 85% water/15% solute; a water bead has 90% water/10% solute.
Will water move in or out?
Out—beaker is hypertonic relative to bead.
In glucose regulation, what do effectors do after the control center detects high blood sugar?
Cells take up glucose; liver stores glucose as glycogen.
How do forests help reduce climate change through photosynthesis?
They absorb CO₂—a greenhouse gas—and store carbon while producing oxygen.
What are the inputs and outputs of glycolysis?
Input: Glucose
Output: 2 pyruvate, 2 ATP, 2 NADH
Explain the difference between endocytosis and exocytosis and give an example of each.
Endocytosis brings materials into the cell (example: nutrients or bacteria being engulfed); exocytosis sends materials out of the cell (example: releasing hormones or neurotransmitters).
Why is drinking too much water dangerous in terms of osmosis?
It creates a hypotonic environment for cells → water enters cells → cells swell and can burst (water intoxication).
In the Homer-ostasis Lab, students recorded body temperature changes over time. What was the overall purpose of this data collection? What type of feedback was used?
To observe how the body uses negative feedback to return temperature to homeostasis after disturbance.
Explain the role of chlorophyll and why it is important for photosynthesis.
Chlorophyll absorbs light energy (mainly red & blue wavelengths) to power the chemical reactions of photosynthesis.
Explain why humans must exhale carbon dioxide during the respiration process.
CO₂ is a waste product from the Krebs cycle; if not removed, it would dissolve in blood and lower pH, disrupting homeostasis.