Biochemistry (Honors Bio)

Homeostasis

The process by which living organisms regulate their internal environment to maintain stable, constant conditions despite external changes. This includes regulation of temperature, pH, and concentrations of ions and nutrients.

Passive Transport

The movement of substances across a cell membrane without the need for energy input, driven by concentration gradients. It includes processes like diffusion, osmosis, and facilitated diffusion. This process allows cells to regulate their internal conditions efficiently.

Diffusion

is the movement of molecules from an area of higher concentration to an area of lower concentration until balance is reached.

Osmosis

is the movement of water molecules across a selectively permeable membrane, moving from an area of higher solute concentration to an area of lower solute concentration.

Isotonic

solution has the same solute concentration as another solution, resulting in no movement of water across the membrane.

Hypotonic

solution has a lower solute concentration than another solution, causing water to move into the cell, potentially leading to cell swelling.

Hypertonic

solution has a higher solute concentration than another solution, causing water to move out of the cell, potentially leading to cell shrinkage.

Facilitated Diffusion

Protein channels that allow large molecules to pass through the cell.

Macromolecules

Polymers of the monomers, includes fats, proteins, carbohydrates, and lipids

Monomers

small things that macromolecules are made of

Protein’s monomer

amino acids

Carbohydrate’s monomer

monosaccharides, simple sugars

Lipid’s monomer

triglyceride

Lipid function

protective layer of cell membrane, insulates

Protein function

catalysts, help metabolism (break things down)

Mitochondria

The powerhouse of the cell, responsible for breaking down glucose into an energy molecule known as adenosine triphosphate (ATP) through chemical reactions.

Vacuole

A membrane bound sac within a cell that function as a storage area for water, nutrients, and waste products.

Cholesterol

lipid that helps regulate membrane flexibility/fluidity and is crucial for various bodily functions.

Cell wall

Barrier of cell, holds shape and protects cell.

Cell membrane

Filters things allowed in or out of the cell, semi-permeable

Nucleus

Control center of cell, holds DNA

Cytoplasm

jelly substance filling the cell, where most chemical reactions occur and contains organelles

Ribosomes

Small structures that build proteins using genetic instructions in the mRNA

Endoplasmic Reticulum

Smooth ER has no ribosomes, rough ER does, network of membranes involved in protein and lipid combination (synthesis)

Golgi Apparatus

Sorts, packages, and transports proteins an lipids to different destinations

mRNA

single stranded molecule that carriers genetic instructions from DNA in the cell’s nucleus to the cytoplasm

Flow of genetic cell information

DNA—>RNA—>Protein

Cilia

Short and numerus structures to move fluid, mucus, or particles along a cell’s surface (can propel a cell)

Flagella

Long(er than cilia) hair like structures used to propel an entire cell through a liquid environment [ex. tail of sperm cell]

Lysosomes

contain enzymes to break down waste materials and cellular debris

Cytoskeleton

Network of protein filaments and tubules in the cytoplasm that provides support to the cell

What is the primary structural component of the cell membrane?

The phospholipid bilayer, which forms a flexible barrier around the cell.

Describe the arrangement of phospholipids in the cell membrane.

Phospholipids form a bilayer with their hydrophilic (water-loving) heads facing outwards towards the aqueous environment and their hydrophobic (water-fearing) tails facing inwards, away from water.

What is the 'Fluid Mosaic Model' of the cell membrane?

It describes the cell membrane as a mosaic of components—including phospholipids, cholesterol, proteins, and carbohydrates—that gives the membrane a fluid character, allowing these components to move laterally within the membrane.

Active transport

the movement of molecules across a cell membrane which requires cellular energy, typically in the form of ATP

Exocytosis

the process where a cell expels substances from inside itself to the outside by having a sac, or vesicle, fuse with the cell membrane

Endocytosis

the process by which cells engulf large particles, fluids, or other substances from the outside and bring them into the cell by forming a membrane-bound vesicle

Pinocytosis

the process by which a cell "drinks" by engulfing small droplets of extracellular fluid along with any dissolved substances within it (type of endocytosis)

Phagocytosis

the process where a cell “eats” or engulfs and digests a large particle, such as a bacterium or dead cell (type of endocytosis)

pH

measures the acidity of a solution

pH Neutrality vs Acid vs Base

Acidic (pH < 7 / Higher H+), Neutral (pH = 7 / Equal OH- and H+), Base (pH > 7 / Higher OH-)

Effect of Temp. and pH on enzymes

They change the shape on enzymes, changing the functions

enzyme structure (and how it works)

3D structure with the big part (enzyme). smaller section (substrate), (connect at active site) (bonds break, makes product)

Denature of enzymes, how its done

Denaturing an enzyme means it loses its three-dimensional shape and biological activity, making it unable to function. This can be done by exposing the enzyme to factors like high temperatures, extreme pH levels, certain chemicals (such as heavy metals or organic solvents), or mechanical agitation.

Why is fat the preferred macromolecule?

for energy storage because it provides the most calories per gram (\(9\) calories vs. \(4\) for carbs and protein) and is stored very efficiently

cellular energy (ATP): structure, made where, get energy from it how?

ATP (adenosine triphosphate) is a molecule with adenine, a ribose sugar, and three phosphate groups. It is made in the mitochondria (in animal cells) or chloroplasts (in plant cells) through cellular respiration or photosynthesis

Cellular respiration (general stages and total ATP yield); equation and location

Cellular respiration is a process with three main stages (Glycolysis, Krebs Cycle, and Electron Transport Chain) that occurs in the cytoplasm and mitochondria, breaking down glucose to produce ATP. Eqaution= C6H12O6=CO2+H2O

Photosynthesis (equation, location, chloroplast vs chlorophyll)

Photosynthesis is the process where plants convert light energy into chemical energy. The equation is CO2+H2O——>C6H12O6, meaning six molecules of carbon dioxide and six molecules of water produce one molecule of glucose (sugar) and six molecules of oxygen. This process occurs inside chloroplasts, the specific organelles that contain chlorophyll, the pigment that absorbs sunlight.