Anatomy Quiz Cellular metabolism/ DNA Synthesis

Cellular Metabolism

Sum of all chemical reactions in the body

Why do we eat? (2 reasons)

1. We need nutrients (carbs, lipids, proteins, nucleic acids). Ex) When you eat something with proteins, the digestive track breaks it down so cells can re use it

2. Provides an energy source. ex) macromolecules allow ATP to be made

Composition of food

Fats, carbs, proteins. only intake small amount of DNA and RNA and they have little amounts of H20, vitamins, and minerals

Decomposition of fat

• no chemical rxn can occur without water'

• to make a fat molecule remove H20 through Anabolism (dehydration synthesis)

• when H20 molecules are present again, fat molecules break down by catabolism (hydrolosis)

Metabolic processes in digestive track vs cells

in the digestive tract catabolism (hydrolosis) is always occurring

In cells anabolism is always occuring (dehydration synthesis)

Catalysts

Enzymes that speed up chemical reactions by lowering activation energy (how much energy you need for a reaction)

Enzyme functions

• subrates fit together like puzzle peices so they can bind to an enzyme and form whatever is nessesary

• an enzymes active site is specific to molecules (substrates)

• form covalent bonds

• a product is formed and released and the enzyme stays the same shape (has 1 function)

Enzymes

• allow reactions to occur very quickly

• all enzymes are proteins

• they are reusable (used over and over agin for chemical reactions)

• part of metabolic pathways

• can build up (anabolism) or break down (catabolism) one substance at a time

Catabolic reactions

substrate binds to an enzyme, the reaction breaks the covalent bond and the products leave the site.

Factors that alter Enzymes

• change in pH → can denature proteins

• high temp or low temp (enzymes wont work)

• harmful chemicals present (destruction of enzymes)

• lots of radiation destroys enzymes

Enzyme negative feedback mechanism

A molecule binds to enzymes and changes the shape of it so it can fit into the next enzyme. once a final product has enough made, the product can inhibit the first enzyme (called the limiting enzyme) causing the enzymes active site to change shape and not let any more molecules bind until more product is needed.

Cofactors

inorganic (made of materials without Carbon) that we get from our diet

• if we dont get enough cofactors we can get diseases

• can act as a catalyst

• allow enzymes to work, are not proteins but bind to enzymes to change them so reactions can occur

Coenzymes

organic (vitamins), without enough disease can occur (not enough vitamin c, scurvy, body can’t synthesize collagen)

• allow enzymes to work, are not proteins but bind to enzymes to change them so reactions can occur

Can glucose move easily across the plasma membrane? iIf so, how does it move across?

Yes, facillitated diffusion

Cellular Resperation

The biochemical process by which cells break down glucose and oxygen to produce energy (ATP), water and CO2.

Total number of ATP made in cellular respiration

36