Question

tain energy (continued)
list at least seven of your body’s cell processes that require energy.
briefly define each.
energy in
cell processes
of each.

Explanation:

To answer this, we recall cell processes that need energy (ATP) and define them:

1. Active Transport: Movement of molecules (e.g., ions) across a cell membrane against their concentration gradient, requiring energy to move from low to high concentration.
2. Protein Synthesis: Process of creating proteins (like enzymes or structural proteins) from amino acids, using energy for transcription (DNA to mRNA) and translation (mRNA to protein).
3. Cell Division (Mitosis/Meiosis): Division of a cell into daughter cells; energy is used for chromosome condensation, spindle formation, and cytokinesis (cell splitting).
4. Muscle Contraction: In muscle cells, actin and myosin filaments slide past each other to shorten muscle fibers; energy powers the cross - bridge cycling between these filaments.
5. DNA Replication: Copying of DNA before cell division; energy is needed for enzymes (like DNA polymerase) to unwind DNA, add nucleotides, and proofread new strands.
6. Cellular Respiration (itself needs energy for start): Though it produces energy, the initial steps (glycolysis, etc.) require ATP to activate glucose breakdown, and the overall process also uses energy for intermediate reactions.
7. Endocytosis/Exocytosis: Endocytosis (e.g., phagocytosis, pinocytosis) is taking in large substances by the cell membrane engulfing them; exocytosis is releasing substances (e.g., hormones) out of the cell. Both need energy to reshape the cell membrane and move vesicles.

Answer:

1. Active Transport: Movement of molecules against concentration gradient, needing energy.
2. Protein Synthesis: Creation of proteins from amino acids, energy for transcription/translation.
3. Cell Division (Mitosis/Meiosis): Cell splits into daughters, energy for chromosome and cell - splitting steps.
4. Muscle Contraction: Actin - myosin sliding in muscles, energy for cross - bridge cycling.
5. DNA Replication: Copying DNA before division, energy for enzyme - mediated reactions.
6. Cellular Respiration (Initial Steps): Glucose breakdown starts with ATP, energy for intermediate reactions.
7. Endocytosis/Exocytosis: Cell takes in/releases substances, energy for membrane reshaping and vesicle movement.