Notes, summaries, assignments, exams, and problems for Secondary education

Key Industries of the Industrial Revolution

The textile and iron industries were the dominant sectors during this period.

The Textile Industry

In the 18th century, there were large volumes of trade in hand-printed cotton fabric from India (known as indianas). The British government boosted the production of cotton fabric within Britain. The mechanization process started with John Kay's flying shuttle (1733), which increased the speed of production and made it possible to weave wider fabrics. This was followed by spinning machines like the spinning jenny, spinning mule, and water frame, which significantly increased productivity.

The Iron Industry

In the 18th century, there was a huge rise in demand for iron to manufacture ships, munitions, machines,... Continue reading "Key Industries of the Industrial Revolution: Textiles, Iron, and Coal" »

Consequences of the Industrial Revolution

New Social Classes

• Bourgeoisie:
  • High bourgeoisie: Business owners, bankers, and large landowners who formed the ruling class.
  • Middle bourgeoisie: Professionals (lawyers, doctors), civil servants, and merchants.
  • Petty bourgeoisie: Employees, shopkeepers, and artisans whose living conditions scarcely differed from those of the proletariat.

The proletariat (workers) were the most disadvantaged social group. They provided the labor force required to operate machinery and were subjected to harsh discipline, where punishments and penalties were common. The first workers to protest against industrialization were the Luddites (England, early 19th century), who destroyed machinery in the belief that it was responsible... Continue reading "Social and Economic Consequences of the Industrial Revolution" »

Key 20th-Century Historical Definitions

Stalinism

Stalinism is a totalitarian political system established by Joseph Stalin in the USSR, beginning in 1927.

Totalitarianism

Totalitarianism is a political system where a single party holds total control over the economy and society, establishing an authoritarian state characterized by the rejection of equality, ultra-nationalism, and militarism.

Sovkhozy

Sovkhozy were state-owned farms under Stalin's government where peasants worked for a salary.

Kolkhozy

Kolkhozy were agricultural cooperatives under Stalin's government where land was owned and farmed collectively.

USSR

The USSR (Union of Soviet Socialist Republics) was a political organization created in 1922 by Vladimir Lenin, composed of Russia and other... Continue reading "Key Historical Terms of the 20th Century: Stalinism to WWII" »

Primary Atmospheric Pollutants

NO2 (Nitrogen Dioxide)

An invisible, irritating gas produced by vehicle combustion and maritime transport.

PM10 (Particulate Matter)

Small particles capable of penetrating the respiratory system. These are present during low temperatures and calm winds, originating from vehicle brakes and Saharan dust.

O3 (Ozone)

Concentrations increase during intense heat waves due to photochemical reactions between nitrogen and organic compounds.

SO2 (Sulphur Dioxide)

A colourless gas with a burnt odour. It reacts with oxygen and water (SO2 + O2 + H2O) to form acid rain, primarily caused by thermal power plants and industrial activities.

CO2 (Carbon Dioxide)

A colourless, odourless, and tasteless gas. While not directly harmful to human... Continue reading "Key Atmospheric Pollutants and Critical Climate Tipping Points" »

The Sense of Hearing and Balance

The sense of hearing is located inside the ears. Sounds are vibrations of the air, received by the eardrum. The eardrum transfers these vibrations to the cochlea, where mechanoreceptors transform them into nerve impulses. These impulses then travel to the brain through the auditory nerve. The sense of balance is also located inside the ear and is closely related to the sense of hearing.

The Organization of the Nervous System

The nervous system is composed of two main divisions: the Central Nervous System (CNS) and the Peripheral Nervous System (PNS).

Central Nervous System (CNS)

• The Central Nervous System (CNS) comprises the brain and the spinal cord. This is where all stimuli are evaluated, and responses are generated.

The Ghost of Coyote Canyon

"Tell me about the old Chumash cemetery and Mr. Richardson," said Nick, as they walked to the barbeque at Blue River Park.

"Oh, you won't believe it, Nick!" said Bill. "People at Coyote Canyon say that on nights when there's a full moon they see an American Indian Warrior. He has a black horse and gallops through the canyon. They think he's a ghost and they're scared!"

"The ghost of an American Indian warrior?" asked Nick, surprised.

"Yeah," said Michelle, "and some people want to sell their new homes!"

"I'm sure Mr. Richardson isn't very happy about that," said Nick.

"No," said Bill, "but he continues building there."

"He and his wife live at Coyote Canyon," said Michelle.

"Have they ever seen the ghost of the warrior?"... Continue reading "The Chumash Cemetery and the Coyote Canyon Legend" »

Idiophones

Idiophone instruments are those in which the sound is produced by the vibration of the instrument itself. They are classified considering the way the sound is produced, that is, how they are played. They can make sounds when hit, concussed, shaken, plucked, scraped, or even rubbed.

Percussion Idiophones

They can be pitched like bar instruments and those we can find in sets like the temple block. They can also be unpitched like the triangle, the gong, the woodblock, or the cajón flamenco.

Concussion Idiophones

Castanets, claves, and cymbals.

Shaken Idiophones

Maracas and rattles.

Plucked Idiophones

The berimbau and the sansa.

Scraped Idiophones

The güiro, the washboard, or the ratchet.

Friction Idiophones

Musical glasses, the glass harmonica,... Continue reading "Musical Instrument Classification: Types and Examples" »

String Instruments

These instruments produce sound through the vibration of one or more strings.

Depending on the vibration technique, we distinguish bowed, plucked, and struck strings.

Bowed String

Sound is produced by rubbing the strings with a bow. They typically have four strings and a similar shape.

• Violin: Smallest, highest pitch.
• Viola: Slightly larger than the violin, middle pitch.
• Violoncello: Larger, lower register, played sitting with an endpin.
• Double Bass: Largest, very low register, played standing.

Plucked String

Sound is produced by plucking the strings with fingers, a pick, or a plectrum.

• Harp: Has 47 strings.
• Guitar: Has six strings and a fretted neck.

Struck String

Sound is produced by striking the strings with hammers activated by a keyboard.... Continue reading "Musical Instrument Families: Strings, Winds, and Percussion" »

Unit 8. Endocrine System

The endocrine system is made up of the endocrine glands and the hormones they produce. Those glands produce hormones, chemical messengers that affect many cell processes (accelerating, delaying, starting, or stopping them). Hormones are transported by blood to all the cells in the body, but they only affect very specific target cells, which have specific receptors for that hormone. The hormone causes changes inside those cells.

Glands release only small quantities of hormones, and once the hormone has carried out its function, it is eliminated from the body.

The hypothalamus, a gland located in the brain, connects the nervous system and the endocrine system. It is one of the most important glands because it controls many... Continue reading "Human Endocrine System: Glands, Hormones and Disorders" »