PROKARYOTE VS. EUKARYOTE
where is the DNA in a prokaryote cells?
floating around the cell.
Where are ribosomes found (free vs. attached) and what do they make?
free in the cytoplasm
Why do they go from high to low concentration (down the gradient)? What energy is needed to go the other way (active transport)?
energy, usually from ATP
How is osmosis different from diffusion?
(Osmosis is only water; diffusion is any particle).
What are the main reactants and products of photosynthesis and cellular respiration?
Photosynthesis uses carbon dioxide and water (plus light energy) to create glucose and oxygen, while cellular respiration uses glucose and oxygen to produce carbon dioxide, water, and ATP (energy), essentially reversing the reactants and products in a vital cycle for life.
where is the prokaryotes cells located?
in bacteria
How do lysosomes break down waste and old parts (like a cell's recycling center)?
engulfing waste and old parts in membrane sacs (autophagosomes), then fusing with these sacs and releasing powerful acidic hydrolase enzymes (like proteases, lipases) that digest the contents into reusable building blocks
Why is the cell membrane "selectively permeable," and what's the function of lipids, proteins, and carbohydrates within it?
its lipid bilayer lets small, nonpolar molecules (like O₂, CO₂) pass freely, while larger or charged substances need help from transport proteins (channels/carriers) to cross, maintaining cell balance (homeostasis)
(Allows water but restricts solutes).
Mitochondria handle energy (respiration), Chloroplasts (plants/algae) do photosynthesis, the Nucleus controls genetics (DNA), Ribosomes make proteins, the ER modifies them, the Golgi packages them, and Lysosomes break down waste
which type of cell is more complex ?
eukaryote cells
What is the Golgi's role in packaging and shipping proteins and lipids?
modifying, sorting, and packaging them into vesicles for delivery to specific destinations inside or outside the cell, ensuring correct cellular function and secretion
What larger or charged molecules (like glucose, ions) need protein channels or carriers?
Larger polar molecules
(Tendency of water to move, highest in pure water, more negative in solutions).
Sunlight provides the energy to power photosynthesis, converting CO2 and water into glucose
is the DNA circular and free-floating (prokaryote) or linear and in the nucleus (eukaryote)?
prokaryotes have circular DNA floating in the cytoplasm (nucleoid), while eukaryotes have linear DNA organized into multiple chromosomes inside the nucleus
What's the difference between rough (protein) and smooth (lipid/detox) ER?
Rough ER (RER) has ribosomes, making it bumpy ("rough"), and synthesizes/modifies proteins for secretion or membranes, while Smooth ER (SER) lacks ribosomes, appearing smooth, and focuses on lipid synthesis (fats, steroids), detoxification, and calcium storage
Why do your fingers prune in the bath (osmosis)? What happens if you drink salt water (cells shrivel)?
water leaves them to dilute the salt, leading to dehydration
(Becomes turgid as water enters).
water vapor constantly exits via transpiration
What are common examples of each (Bacteria, Archaea for prokaryotes; Animals, Plants, Fungi, Protists for eukaryotes)?
E. coli (Bacteria) and methanogens (Archaea)
How does the nucleus control cell activities, and what's the difference between DNA, chromatin, and chromosomes?
by housing DNA
How does water move, and what's the difference between hypotonic, hypertonic, and isotonic solutions? (e.g., Why do cells swell/shrivel?)
Water moves via osmosis, from high water concentration (low solute) to low water concentration (high solute) across a semipermeable membrane, causing cells to swell in hypotonic (water enters), shrink in hypertonic (water leaves)
(Osmosis is only water; diffusion is any particle).
stored primarily through photosynthesis (plants convert it to chemical energy/sugars), thermal mass (buildings absorb heat), or mechanical/electrical systems (batteries, pumped hydro)