DOST JLSS Scholarship Science Reviewer

Comprehensive vocabulary flashcards covering Biology, Chemistry, Physics, Earth Science, and general scientific history for the DOST JLSS scholarship exam.

Micro molecules

Small organic molecules such as amino acids, sugars, and fatty acids that serve as the framework for macromolecules.

Macromolecule

Large organic molecules called polymers built from smaller molecules called monomers; examples include carbohydrates, lipids, proteins, and nucleic acids.

Monosaccharides

Simple sugars, such as fructose, glucose, and galactose, which are the main fuel cells use for cellular work.

Disaccharides

Molecules made by joining two monosaccharides, such as sucrose (Table Sugar), lactose (Milk Sugar), and maltose (Grain sugar).

Starch

A polysaccharide found in plants, such as potatoes and rice, used for energy storage.

Glycogen

The stored form of sugar found in skeletal muscles and the liver.

Cellulose

A dietary fiber found on plant walls and a major wood component that humans cannot break down.

Hydrophobic

A property of substances, like lipids, that do not mix with water; literally translates to "water-fearing."

Saturated Fatty Acids

Usually animal fats that exist as solids at room temperature, such as butter or margarine.

Unsaturated Fatty Acids

Plant oils that tend to be low in saturated fatty acids and exist as liquids at room temperature.

Cholesterol

The "base" steroid from which the body produces other steroids like testosterone, estrogen, and progesterone.

Proteins

Molecules made from amino acid monomers used to build cells, act as hormones and enzymes, and perform much of the cellular work.

ATP (Adenosine Triphosphate)

The cellular energy molecule made of a nucleotide with 3 phosphate groups; energy is stored in the chemical phosphate bonds.

Homeostasis

The characteristic of living organisms to maintain internal balance.

Unicellular

Organisms composed of only one cell, such as bacteria, protozoa, and ciliates.

Multicellular

Organisms composed of many cells that may organize into tissues and organ systems.

Cell Membrane

An outer covering composed of a double layer of phospholipids that controls what enters or leaves the cell.

Cell Wall

A nonliving layer found outside the cell membrane in plants (made of cellulose), fungi (chitin), and bacteria (peptidoglycan).

Nucleolus

A dark staining body inside the nucleus that forms RNA molecules for the synthesis of ribosomes.

Cytoskeleton

A netlike framework of microtubules and filaments that helps maintain cell shape, internal organization, and provides mechanical support.

S Phase (Synthesis Phase)

The part of interphase during which DNA replication takes place.

Mitosis

A process where a cell replicates its chromosomes and segregates them, producing two identical nuclei.

Meiosis

A process where a single cell divides twice to produce four granddaughter cells containing half the original amount of genetic information.

Mendelian Genetics

The study of certain patterns of how traits are passed from parents to offspring based on unit factors, dominance, and segregation.

Archaebacteria

The oldest living organisms on Earth that can tolerate extreme environments like high temperatures and high salinity.

Krebs Cycle

Also known as the Citric Acid Cycle; it occurs in the mitochondrial matrix and produces $CO_2$, $NADH$, $FADH_2$, and $ATP$.

Simple Random Sampling

A probability sampling technique where each possible sample has an equal probability of selection.

Stratified Random Sampling

A sampling technique obtained by dividing the population into distinct groups known as strata and taking a random sample from each.

Entropy

A measurement indicating the level of disorder within a system, expressed by the equation $\triangle S = \frac{Q}{T}$ with the unit $J/K$.

Heisenberg Uncertainty Principle

The principle stating it is impossible to simultaneously know both the position and momentum of a particle with absolute certainty.

Metallic Bond

The electrostatic attraction between electron clouds and metal nuclei.

Intensive Property

A physical property independent of the quantity of the substance, including boiling point, color, and temperature.

Extensive Property

A physical property that depends on the quantity of the substance, such as volume, mass, and weight.

J.J. Thomson (1896)

The physicist who discovered electrons using a cathode ray tube and proposed the Plum Pudding Model.

Ernest Rutherford (1909)

The scientist who discovered the nucleus using the Gold Foil experiment and named the positive charge the "proton."

Dmitri Mendeleev

The inventor of the modern periodic table, which he initially arranged in order of increasing atomic weight.

Halogens

Group 17 elements consisting of highly reactive nonmetals that form diatomic molecules.

Ion

An atom or group of atoms that has a net positive or negative charge.

Combustion Reaction

A reaction involving a hydrocarbon and oxygen resulting in heat, light, carbon dioxide, and water.

Electrolytes

Substances that ionize in solution and conduct electricity; classified as strong or weak based on the degree of ionization.

Br%f8nsted-Lowry Acid

A substance that acts as a proton ($H^+$) donor.

Lewis Base

A substance that acts as an electron pair donor.

Reducing Agent

A substance that donates electrons and undergoes oxidation.

Aufbau Principle

The rule in quantum theory detailing the sequence in which electron orbitals are filled.

Electronegativity

The ability of an atom to attract electrons in a chemical bond.

VSEPR Model

Valence-shell electron-pair repulsion model used to account for the geometric arrangement of electron pairs around a central atom.

Catalyst

A species that changes the rate of a reaction by providing a lower activation energy pathway without being consumed.

First Law of Thermodynamics

The Law of Conservation of Energy, stating energy can neither be created nor destroyed, only transformed.

Zeroeth Law of Thermodynamics

States that if two bodies are individually in equilibrium with a third body, then the first two are in thermal equilibrium with each other.

Functional Groups

Specific groups of atoms such as Carbonyl ($C=O$), Hydroxyl ($-OH$), and Carboxyl ($-COOH$) that determine the properties of organic molecules.

Alkenes

Hydrocarbons characterized by the presence of double bonds.

Isomer

The product of a rearrangement reaction that has the same molecular formula but a different structural arrangement.

Enantiomers

Molecules that are non-superimposable mirror images of each other.

Molarity (M)

A unit of concentration defined as the number of moles of solute per liter of solution ($M = \frac{mol}{L}$).

Boyle's Law

States that pressure and volume are inversely proportional at constant temperature ($P_1V_1 = P_2V_2$).

Newton's Second Law

States that the force required to accelerate an object is equal to its mass times acceleration ($F = ma$).

Kinetic Energy (K.E.)

The energy associated with an object's motion, calculated using the formula $K. E = \frac{1}{2}mv^2$.

Potential Energy

Stored energy in a system, often calculated as gravitational potential energy ($PE = m \times g \times h$).

Ohm's Law

The relationship between electric current, potential difference (voltage), and resistance ($V = IR$).

Law of Reflection

States that the angle of incidence is equal to the angle of reflection.

Snell's Law

The Law of Refraction which describes how light changes speed and direction when entering a different medium.

Igneous Rocks

Rocks formed through the cooling and solidification of magma or lava, such as basalt or granite.

Metamorphic Rocks

Existing rock types transformed by heat and pressure (metamorphism), such as marble and slate.

Pangea

The single vast continent proposed by Alfred Wegener that existed around 250 million years ago.

Brittle Deformation

Occurs when rocks break or fracture under stress, common in the upper crust where temperature and pressure are low.

Ductile Deformation

Occurs when rocks bend or flow under stress, common in the lower crust and mantle.

Phreatic Eruption

The type of eruption emitted by Mt. Kanlaon in 2024, involving steam and gas from pre-existing solid rock.

Taxonomy

The science of classifying organisms into hierarchical categories (Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species).

Cuneiform

The first known writing system, invented by the Sumerians using wedge-shaped symbols on clay tablets.

Nicolaus Copernicus

The astronomer who proposed the heliocentric model of the solar system where planets orbit the Sun.