Biochemistry
A mutation changes the shape of an enzyme’s active site. Predict how this affects the reaction rate and explain why.
Substrate won’t bind properly so rate decreases or stops
A cell placed in a hypertonic solution shrinks. Explain why water moved out of the cell.
Osmosis toward higher solute concentration
Why must energy from sunlight be converted to chemical energy in photosynthesis?
Cells use chemical energy not light directly
Why must DNA be replicated before mitosis begins?
Each daughter cell needs full set
Why is DNA considered the blueprint of the cell?
Stores genetic instructions
Explain how hydrogen bonding between water molecules contributes to temperature stability in organisms.
High heat capacity absorbs heat without big temp change
Why can oxygen cross the membrane easily but glucose cannot without help?
Oxygen is small/nonpolar and glucose is large/polar
Explain how ATP releases energy when a phosphate is removed.
Breaking bond releases stored energy
How do checkpoints protect organisms from abnormal cell division?
Stop damaged cells
How does meiosis increase genetic diversity?
Crossing over & independent assortment
Why are proteins able to perform many different functions in cells?
Different amino acid sequences fold into unique shapes
How do membrane proteins help maintain homeostasis?
Control transport and signaling
How does glucose made in photosynthesis support cellular respiration?
It is broken down to produce ATP
Predict consequences if mitosis occurs without cytokinesis.
One cell with multiple nuclei
Explain why transcription occurs in nucleus and translation in cytoplasm.
DNA protected; ribosomes in cytoplasm
Predict what happens to enzyme activity if pH becomes extremely acidic.
Enzyme denatures and loses function
Predict effects if mitochondria lost inner membrane folds.
Less ATP produced
Predict what would happen if oxygen was unavailable in respiration.
ETC stops; ATP production decreases
Explain how a signal molecule triggers a response inside a cell.
Binds receptor → cascade
Predict how a frameshift mutation affects protein production.
Alters many amino acids
How does carbon’s bonding ability support biological complexity?
Forms chains, rings, and diverse molecules
Explain how structure of phospholipids leads to membrane formation in water.
Hydrophilic heads outward, hydrophobic inward
Why are electron carriers essential in both photosynthesis and respiration?
Transport high-energy electrons
Why is communication necessary for tissue development?
Coordinates growth/differentiation
How does gene regulation allow cells with same DNA to have different functions?
Different genes turned on/off