chp 5: the dynamic cell

we eat food that is stored as potential energy. we can then walk which converts that potential energy into kinetic energy

stored energy

the energy of motion

how the energy contained in food is measured. calories in food actually means kilocalories (1,000 calories)

energy cannot be created nor can it be destroyed. it can only be transformed from one form to another

reveals that some energy is lost, often as heat, for every energy transformation

relative amount of disorganization. the default state

energy

a nucleotide with three phosphate groups

energy is stored as a phosphate group and added to ADP to make ATP; energy is released as a phosphate group is removed

sun -> chloroplast -> mitochondria

we consume plants that have used their chloroplasts to photosynthesize and create carbohydrate or animals that have consumed plants. oxygen and nutrient molecules enter our mitochondria which produces ATP

it stabilizes our body's temperature; maintains homeostasis

they make chemical reactions happen faster than under normal conditions; less energy used

series of linked reactions

proteins

breakdown reaction; breaks down molecules into smaller units

synthesis reaction; constructs macromolecules from smaller units

to speed it up

molecule that gets manipulated

the change in the shape of the active site facilitates the reaction; induced fit

an active enzyme is prevented from combining with its substrate; activity of almost every enzyme in a cell regulated by this; occurs when a product is in abundance

something that dissolves in a liquid

a liquid that dissolves a solute

uses transport proteins in a plasma membrane

same solute, concentration of solutes same on both sides. cell neither gains or loses its water

high solute, concentration of solute outside cell more than inside cell, cell loses water

low solute, concentration of solute outside cell lower than inside cell, cell gains water

occurs when plant cells are placed in a hypertonic solution. plant cells get turgid (stiff)

molecules move down their concentration gradient until equilibrium is achieved and they are distributed equally

the diffusion of wtaer across a semipermeable membrane, from an area of higher concentration to an area of lower concentration

the cell will lose water and shrivel since there is a higher concentration of solute outside the cell than inside the cell; it will shrivel and undergo plasmolysis. the water flows towards the inside of the tube

requires the input of energy to move molecules against a concentration gradient (e.g. sodium-potassium pump)

ATP

transports macromolecules out of a cell via vesicle formation and often results in secretion

transports macromoleules into a cell via vesicle formation

requires not metabolic energy and moves substances from an area of higher concentration to an area of lower concentration

macromolecules are too big for transport proteins, so vesicles formation takes care of it