Freshman Biology Midterm Prep

Photosynthesis

process by which the energy of sunlight is converted into the energy of glucose

Chlorophyll

pigment inside the chloroplast absorbs light for photosynthesis

Chemical Bond Energy

the energy stored in the bonds holding atoms together, representing the strength and stability of a molecule

Heterotrophs

obtain food from other organisms

Autotrophs

Make their food from the sun

Photosynthesis occurs

in the chloroplasts

ATP

Adenosine Triphosphate the essential energy currency for all living cells

ADP

Adenosine Diphosphate a crucial molecule in cellular energy transfer, essentially the "uncharged" form of ATP

Cell Wall

a tough, protective, semi-rigid outer layer found in plants, fungi, bacteria, algae, and some archaea, but not animal cells

Chloroplast

a vital organelle in plant and algae cells, famous for performing photosynthesis, where it uses sunlight, water, and carbon dioxide to create energy (sugars) and release oxygen

Mitochondria

essential, double-membrane organelles in eukaryotic cells, often called the "powerhouses" because they generate most of the cell's energy (ATP) through cellular respiration, but also manage cell death, calcium signaling, and molecule production

Cellular Respiration

the vital metabolic process where cells break down glucose (food) and oxygen to create usable energy in the form of ATP (adenosine triphosphate), releasing carbon dioxide and water as byproducts

Calvin Cycle

the vital metabolic process where cells break down glucose (food) and oxygen to create usable energy in the form of ATP (adenosine triphosphate), releasing carbon dioxide and water as byproducts

6CO2 + 6H2O

This is the chemical equation for photosynthesis, representing the conversion of carbon dioxide and water into glucose and oxygen using sunlight.

AMP

Adenosine Monophosphate, an energy-related molecule in cells

Light Reactions

the first stage of photosynthesis, occurring in the thylakoid membranes of chloroplasts, where sunlight is converted into chemical energy (ATP and NADPH) and oxygen is released as a byproduct

Glycolysis

a fundamental metabolic pathway occurring in the cytoplasm that breaks down one six-carbon glucose molecule into two three-carbon pyruvate molecules, generating a net of two ATP (energy) and two NADH molecules

Krebs Cycle

the cell's central energy-releasing engine, taking broken-down food bits (acetyl-CoA) and running them through a circular series of reactions in the mitochondria to produce high-energy carriers (NADH, FADH2) and a little ATP, while releasing carbon dioxide (the stuff we breathe out) and regenerating its starting molecule, oxaloacetate, to keep the cycle going for more energy production

photolysis

the chemical breakdown of molecules using light energy

NADP+

a crucial coenzyme, carries electrons, the oxidized form of NADPH

Electron Transport Chain

a series of protein complexes in cell membranes (mitochondria in eukaryotes) that transfer electrons from NADH and FADH2 (from food breakdown) to oxygen

Aerobic

relating to, involving, or requiring free oxygen.

Anaerobic

without oxygen

Alcoholic Fermentation

an anaerobic (oxygen-free) biochemical process where yeast or bacteria convert sugars (like glucose) into cellular energy, producing ethanol (alcohol) and carbon dioxide as byproducts, crucial for making beer, wine, and bread

Lactic Acid Fermentation

an anaerobic (no oxygen) metabolic process where microorganisms like bacteria convert sugars (like glucose) into energy and lactic acid

Fatty Acid

the building blocks of fats in food and the body, with key functions in energy storage and cellular structure

Building Block

Amino acids, lipids, and nucleotides. Each is used by our cells to make more complex molecules and structures necessary for life.

Organic

derived from living things or produced naturally

Carbohydrate

essential organic molecules (sugars, starches, fibers) made of carbon, hydrogen, and oxygen, serving as the body's primary energy source, structural components (like cellulose in plants, chitin in insects), and energy storage (glycogen in animals, starch in plants)

Lipid

a diverse group of hydrophobic (water-insoluble) organic molecules

Nucleic Acids (DNA/RNA)

essential macromolecules that store, transmit, and express genetic information, acting as life's blueprints and instructions for building and operating cells, primarily by directing protein synthesis

Protein

a vital building block for your body, made of smaller units called amino acids, that builds and repairs tissues (like muscle, skin, hair) and carries out essential jobs like speeding up chemical reactions (enzymes) and fighting infections (antibodies)

Elements

a pure substance made of only one type of atom (like Carbon, Oxygen, Hydrogen) that can't be broken down by ordinary chemical means

CHONPS

a biological acronym for the six most abundant elements in living organisms: Carbon (C), Hydrogen (H), Nitrogen (N), Oxygen (O), Phosphorus (P), and Sulfur (S)

Lysosome

a membrane-bound cell organelle that contains digestive enzymes

Food Web

shows the complex feeding relationships in an ecosystem, illustrating how energy flows through interconnected food chains, from producers (plants) to various levels of consumers (herbivores, carnivores, omnivores) and finally to decomposers

Energy Transfer

the movement and transformation of energy from one system (like the sun) to another (like an organism) or between organisms

Producer

an organism that makes it’s own food.

Consumer

an organism that gets energy and nutrients by eating other organisms (plants or animals) or organic matter, as it cannot produce its own food like producers (autotrophs)

Carbon

the fundamental building block of life, forming the "backbone" of all organic molecules like carbohydrates, lipids, proteins, and nucleic acids (DNA/RNA) due to its unique ability to form four stable covalent bonds with itself and other elements (O, H, N, P)

Sugar

a sweet, soluble carbohydrate, typically a simple sugar (monosaccharide like glucose, fructose) or a double sugar (disaccharide like sucrose, lactose) that serves as a primary energy source, building block for larger carbs (starch, cellulose), and structural component in cells

Storage

the process where organisms retain essential substances like energy (fats, glycogen, starch), nutrients (vitamins, minerals, amino acids), water, and even waste or genetic info (DNA) in cells or specialized organs (roots, fat) for future use, ensuring survival, growth, or reproduction, often using structures like vacuoles or fat bodies

Decompose

the crucial process where dead organic matter (like plants and animals) is broken down into simpler inorganic substances (like carbon dioxide, water, and minerals) by decomposers (fungi, bacteria, worms) as part of the nutrient cycle, recycling essential elements back into the ecosystem for living organisms to reuse

Bacteria

single-celled microorganisms that are prokaryotes

Phosphate Group

a crucial molecule consisting of one phosphorus atom bonded to four oxygen atoms

Vacuole

the collective functions and structures of vacuoles, which are membrane-bound sacs in cells (especially plants, fungi, protists) that store nutrients, water, and waste, maintain cell shape (turgor pressure), and aid in digestion and detoxification

DNA

the fundamental molecule, Deoxyribonucleic Acid (DNA), that carries genetic instructions for an organism's development, functioning, and reproduction, organized into units called genes and packaged into chromosomes, with its double helix structure made of nucleotides containing sugar, phosphate, and one of four bases (A, T, C, G)

Transpiration

the process where plants release water vapor into the atmosphere, primarily through tiny pores called stomata on their leaves, acting like plant sweat to regulate temperature and pull water and nutrients up from the roots

Respiration

the physical act of breathing (breathing in oxygen, breathing out carbon dioxide) and the vital cellular process where organisms break down food (like glucose) using oxygen to release energy (ATP) for life functions, producing carbon dioxide and water as byproducts

Glucose

a simple sugar, a basic carbohydrate, and the body's main source of quick energy, found in our blood (blood sugar) and derived from the food we eat, fueling cells for all functions

Light Energy

the electromagnetic radiation (photons) from sources like the sun, crucial for life, driving processes like photosynthesis in plants (converting it to chemical energy for food)

Fungi

a kingdom of diverse eukaryotic organisms (like yeasts, molds, and mushrooms) that are heterotrophs, meaning they absorb nutrients from organic matter, unlike plants (which photosynthesize) or animals (which ingest food)

Plants

a living organism from the kingdom Plantae, characterized by being multicellular, eukaryotic, and primarily photosynthetic

Animals

is a multicellular, eukaryotic organism that is heterotrophic (eats other organisms for energy), typically has specialized tissues like muscles and nerves, lacks cell walls, and develops from a blastula in the embryo

Protists

a diverse group of eukaryotic organisms (cells with a nucleus) that are not animals, plants, or fungi

Ribosomes

essential molecular machines in all cells that synthesize proteins by translating messenger RNA (mRNA) into chains of amino acids

Active Transport

the cellular process of moving molecules or ions across a cell membrane against their concentration gradient (from low to high concentration)

Osmosis

the movement of water across a special, semi-permeable membrane from an area where there's more water (less stuff dissolved in it) to an area where there's less water (more stuff dissolved in it), trying to even things out

Equilibrium

a state of dynamic balance where opposing forces or processes are equal, leading to stability, often seen as homeostasis

Multicellular

describes organisms made of more than one cell

Passive Transport

the movement of substances across a cell membrane from a high concentration to a low concentration (down the gradient), requiring no cellular energy (ATP), driven by random molecular motion and increasing entropy

Unicellular

organisms made of just one cell that performs all life functions

Amino Acid

the essential organic building blocks of proteins

Monosaccharide

the simplest sugar unit, a fundamental carbohydrate building block (like glucose, fructose, galactose) that can't be broken down further, serving as immediate energy (e.g., in cellular respiration) or linking to form complex carbohydrates (disaccharides, polysaccharides) for storage (starch) or structure (cellulose)

The Suffix “-ose”

indicates a sugar or a carbohydrate.

The Suffix “-ase”

almost always indicates an enzyme

Isotonic

describes a solution or environment with the same solute concentration as another, usually a cell's interior, resulting in no net movement of water by osmosis, keeping the cell's volume stable, with water moving evenly in and out

Endocytosis

a mechanism for internalizing large extracellular molecules (e.g., proteins), insoluble particles, or even microorganisms.

Phagocytosis

the degradation of the engulfed particle inside a phagolysosome

Primary Consumer

second trophic level in a food chain, herbivores. Ooccupying the first level/consumers above autotrophs (plants). Examples: Caterpillars, rabbits, grasshoppers, deer, mice, hummingbirds, and zooplankton.

Secondary Consumer

an organism that feeds on primary consumers (herbivores) in a food chain, acting as a carnivore or omnivore, occupying the third trophic level after producers and primary consumers