Cell Structure
What organelle contains DNA and acts as the cell's control center?
Nucleus
What type of transport moves substances from high concentration to low concentration without using cellular energy?
Passive transport/diffusion.
Which macromolecule is the cell's main source of quick energy?
Carbohydrates
What type of biological molecule are enzymes?
Protein
What is the primary purpose of homeostasis?
Maintaining stable internal conditions.
Which organelle builds proteins, and which organelle modifies, sorts, and transports those proteins?
Ribosomes build proteins; the Golgi apparatus modifies, sorts, and transports proteins.
What is the movement of water across a selectively permeable membrane called?
Osmosis
What are the building blocks of proteins?
Amino acids.
What does the substrate turn into after the reaction is complete
Product
What is one major difference between a prokaryotic cell and a eukaryotic cell?
Prokaryotes lack a nucleus and membrane-bound organelles; eukaryotes have them.
A cell contains a nucleus, mitochondria, ER, and Golgi apparatus. Is this cell prokaryotic or eukaryotic? Explain how you know.
Eukaryotic; it contains a nucleus and membrane-bound organelles.
A cell uses ATP to move a substance from an area of low concentration to an area of high concentration. What type of transport is occurring?
Active transport
A plant cell needs a molecule for long-term energy storage, while also using another macromolecule for quick energy. Identify the two macromolecules and explain the different roles they play.
Lipids are used for long-term energy storage, while carbohydrates provide quick energy.
What part of an enzyme does the substrate bind to?
Active site
Explain how the Phospholipid Bilayer contributes to maintaining homeostasis.
The membrane regulates what enters and leaves the cell.
A cell produces a protein that will eventually be transported outside the cell. Which organelles would most directly participate in making, modifying, and transporting this protein?
Ribosome/rough ER → Golgi apparatus → transport
A cell is placed in a solution where water moves into the cell by osmosis. What does this tell you about the relative concentration of water inside and outside the cell?
Water is moving toward the area with lower water concentration/higher solute concentration
A monomer of DNA is a nucleotide, and the components of a nucleotide are?
What is a Phosphate, Sugar, and Nitrogen Base
Why does an enzyme stop functioning properly when its shape changes?
Enzyme function depends on its shape; changing its shape can prevent the substrate from fitting properly.
Explain how the cell membrane, transport mechanisms, and homeostasis are connected.
The membrane controls transport into/out of the cell, while the cell uses transport mechanisms to regulate internal conditions.
A cell has DNA but no nucleus or membrane-bound organelles. It is also relatively small and simple. Identify the type of cell and explain the evidence supporting your answer.
Prokaryotic; it has DNA but lacks a nucleus and membrane-bound organelles and is simpler/smaller.
A cell needs to move a substance from low concentration to high concentration. Explain why passive transport cannot accomplish this and identify the process the cell could use instead.
Passive transport moves down the concentration gradient and does not require ATP; moving low → high requires energy and can involve protein pumps/active transport
A mutation changes the DNA sequence for an enzyme. Trace the possible pathway from DNA → RNA → protein → enzyme shape → enzyme function, explaining how the mutation could ultimately affect a cell's traits.
DNA can be transcribed into RNA; RNA directs protein synthesis; a mutation can alter the amino acid sequence, potentially changing enzyme shape and therefore enzyme function and traits.
Why does an enzyme stop functioning properly when its shape changes?
Enzyme function depends on its shape; changing its shape can prevent the substrate from fitting properly to the active site.
A cell experiences a change in its environment that disrupt some enzymes function. Vacuoles no longer work properly and the cell membrane can no longer transport materials. Explain how these two changes could interfere with the cell's ability to maintain homeostasis.
together these can prevent the cell from maintaining stable internal conditions.