Cell Theory and Cell Types
What are the three major ideas of cell theory?
All living things are made of cells
Cells are the basic unit of life
All cells come from preexisting cells.
I contain DNA and help control the activities of a eukaryotic cell. Who am I?
Nucleus
Why don't all cells in your body have the same shape?
Different cells have different functions/jobs, and their structures help them perform those functions.
What organelle is the main site of photosynthesis?
Chloroplasts
What organelle is the main site of aerobic cellular respiration?
Mitochondria
Name two structures found in BOTH prokaryotic and eukaryotic cells.
Any two: cell membrane, cytoplasm, ribosomes, DNA.
I build proteins using instructions from genetic material. Who am I?
Ribosome
Which cell structure helps maintain a cell's shape and allows cells to become specialized in shape?
Cytoskeleton
Complete the simplified relationship:
Carbon dioxide + water + light energy →
___?___ + ___?___
Glucose + oxygen
What is the main usable energy molecule made during cellular respiration?
ATP
A cell contains DNA, ribosomes, cytoplasm, and a cell membrane, but no nucleus. What type of cell is it?
Prokaryotic
A cell suddenly loses its ability to break down old molecules and cellular waste. Which organelle is most likely malfunctioning?
Lysosome
Why would a muscle cell contain many mitochondria?
Muscle cells require large amounts of energy/ATP for contraction.
What energy transformation occurs during photosynthesis?
Radiant/light energy → chemical energy stored in glucose.
What happens to the chemical energy stored in glucose during cellular respiration?
Some of it is transferred into ATP that cells can use.
A scientist discovers a cell containing mitochondria. What type of cell is this?
It is eukaryotic because mitochondria are membrane-bound organelles.
Which organelle is a network of passageways that helps transport materials throughout the cell? (Hint: There are two types of this organelle)
Endoplasmic reticulum (ER)
(remember: Golgi bodies modify, sort, and package proteins/materials for delivery but the ER is responsible for the transportation)
A neuron has long extensions that may reach far from the main cell body. How does this structure help the neuron perform its job?
The long extensions allow it to send/receive signals over long distances.
A plant is placed in darkness. Would you expect the amount of oxygen produced through photosynthesis to increase or decrease?
Decrease, because photosynthesis requires light energy.
Which produces more ATP per glucose molecule: aerobic cellular respiration or anaerobic respiration (fermentation)?
aerobic cellular respiration
(remember: when oxygen is present, cellular respiration makes significantly more ATP than fermentation which occurs in the cytoplasm when oxygen is not present)
Cell theory explains where new cells come from today. What major question does traditional cell theory NOT explain?
How the first cells originated.
A cell needs a large amount of energy to do its job. Which organelle would you expect that cell to have a lot of?
Mitochondria
A cell has many tiny hair-like structures called cilia on its surface. How could these structures help the cell perform its job?
The cilia can trap and move materials across the surface of the cell (example: dust and germs in your airways).
A plant's stomata close during extremely hot, dry weather. This prevents CO₂ from entering the leaf. Predict what happens to the rate of photosynthesis and explain why.
Photosynthesis decreases because CO₂ is a reactant needed to make glucose.
Remember: CO2+H2O+Light → C6H12O6 + O2
A plant is placed in complete darkness for several hours. Is cellular respiration occurring during this time? Explain.
Yes. Plants perform cellular respiration continuously to release usable energy from glucose. Photosynthesis requires light, but cellular respiration does not.