Science Notes Flashcards

Vocabulary flashcards based on science lecture notes.

Protons

Positively charged particles located in the nucleus of an atom.

Neutrons

Neutral particles (no charge) located in the nucleus of an atom.

Electrons

Negatively charged particles that move around the nucleus in energy levels or shells.

Atomic Number

The number of protons in the nucleus of an atom; defines the element.

Mass Number

The number of protons and neutrons in the nucleus of an atom.

Isotopes

Atoms of the same element with different numbers of neutrons.

Cations

Ions formed when an atom loses electrons; positively charged.

Anions

Ions formed when an atom gains electrons; negatively charged.

Dimitri Mendeleev

Scientist who created the first widely recognised periodic table, arranging elements by increasing atomic mass and grouping them by similar chemical properties.

Henry Moseley

Scientist who introduced the concept of atomic number and revised the periodic table based on it.

Glenn T. Seaborg

Scientist who discovered several transuranium elements and moved them to a separate series below the main periodic table (the actinide series).

Spectroscopy

A technique that analyses the light emitted or absorbed by elements, leading to a better understanding of the atomic structure and electronic configurations.

X-ray Crystallography

A technique that determines the arrangement of atoms within crystals, providing insights into the properties of elements and compounds.

Groups (Periodic Table)

Vertical columns in the periodic table (1-18) where elements share similar chemical properties due to the same number of valence electrons.

Periods (Periodic Table)

Horizontal rows in the periodic table where elements have the same number of electron shells but increasing atomic number.

Atomic Radius

The distance from the nucleus to the outermost electron shell in an atom.

Ionization Energy

The energy required to remove an electron from an atom.

Electronegativity

The ability of an atom to attract bonding electrons.

Metallic Character

The properties associated with metals, such as conductivity, malleability, and lustre.

Alkali Metals

Group 1 elements; soft, low density, highly reactive, form +1 ions.

Alkaline Earth Metals

Group 2 elements; reactive (less than alkali metals), harder, form +2 ions.

Halogens

Group 17 elements; non-metals, form -1 ions, exist in various physical states.

Nobel Gases

Group 18 elements; chemically inert due to a full valence shell and colourless gases.

Transition Metals

d-block elements; variable oxidation states, form colorful compounds, good conductors of electricity.

Metalloids

Elements that exhibit properties of both metals and non-metals; semiconductors.

Human Reproductive System

Biological system responsible for producing gametes, facilitating fertilization, and supporting the development of offspring.

Testes (Testicles)

Male reproductive organs that produce sperm and testosterone.

Ovaries

Female reproductive organs that produce eggs (ova) and female hormones (estrogen and progesterone).

Genetics

The study of heredity, which is the passing of genetic information (traits) from parents to offspring.

Mitosis

A type of cell division that produces two identical daughter cells.

Meiosis

A specialized type of cell division that produces gametes (sperm and eggs) with half the number of chromosomes as the parent cell.

Gregor Mendel

The 'Father of Genetics,' was an Austrian monk who discovered that traits are inherited in predictable patterns.

Dominant Trait

A trait that is expressed even if only one copy of the allele is present.

Recessive Trait

A trait that is expressed only when both copies of the allele are recessive.

Pedigree

A diagram that shows the inheritance of traits across generations in a family.

Chromosomes

Thread-like structures found in the nucleus of a cell that carry genetic information.

DNA (Deoxyribonucleic Acid)

A molecule that contains the genetic instructions for an organism’s growth, development, functioning, and reproduction.

Genes

Segments of DNA on chromosomes that code for specific proteins.

Double Helix

The structure of DNA, consisting of two long strands twisted into a spiral.

Nitrogenous Base

A molecule that contains nitrogen and has chemical properties of a base

DNA Replication

The process by which DNA makes an identical copy of itself during cell division.

Genotype

The genetic makeup of an organism.

Phenotype

The observable traits resulting from the genotype and environmental influence.

Mutation

A change in the structure of the genetic material (DNA sequence).

Natural Selection

The process where organisms with favourable traits have a higher chance of survival and reproduction, driving evolution over time.

Adaptation

A trait that improves an organism’s ability to survive and reproduce in its environment.

Speciation

Formation of new species due to evolutionary changes.

Coevolution

The process by which two or more species influence each other’s evolution due to their interactions over time.

Directional Change

When environmental changes shift the traits favoured by natural selection.

DNA Fingerprinting

Identifies individuals based on unique DNA patterns.

Recombinant DNA Technology

Combines DNA from two or more sources to create new genetic combinations.

Cloning

Creating a genetically identical copy of an organism, cell, or DNA sequence.

Genome Sequencing

Understanding the complete DNA sequences of organisms (e.g., the Human Genome Project).

CRISPR-Cas9

A revolutionary gene-editing technology that allows precise DNA modifications.

Vaccine

A biological preparation that provides active acquired immunity to a particular infectious disease

Vaccine Hesitancy

Delay in acceptance or refusal of vaccination despite availability of vaccination services

In Vitro Fertilisation

A process in which an egg is fertilised by sperm outside the body: in vitro

Infectious Disease

Caused by pathogens (e.g., bacteria, viruses, fungi, parasites) and is contagious.

Non-Infectious Diseases

Not caused by pathogens; often genetic, lifestyle-related, or environmental and is not contagious.

Endocrine System Composition

Composed of glands like the pituitary, thyroid, adrenal, pancreas, and gonads; secretes hormones that regulate processes like growth, metabolism, and reproduction.

Bioinformatics

The use of information technology to analyze and store biological data, particularly DNA sequences.