Atoms and Matter Overview

Atoms and Matter

• Atoms are the fundamental building blocks of all matter.
• Composed of subatomic particles: neutrons, protons, and electrons.
• Matter occupies space and has mass, consisting of elements which cannot be chemically broken down.

Energy and Matter

• Energy is the ability to perform work.
• According to Einstein’s theory, energy and matter can be converted into each other.

Elements in the Human Body

• Approximately 99% of the human body is made up of six elements: oxygen, hydrogen, nitrogen, carbon, calcium, and phosphorus.
• Another five elements (sulfur, potassium, sodium, chlorine, and magnesium) comprise about 0.85% of body mass.
• Trace elements are minerals present in tiny amounts in living tissues, useful in determining the age of biological remains.

Radioisotopes

• Unstable chemical elements that emit radiation while stabilizing.
• Used in imaging and treatment within the field of medicine.
• Pose dangers to health and environment, with notable disasters at Fukushima (2011) and Chernobyl (1986).

Fukushima Disaster

• Triggered by an earthquake and tsunami, releasing radioactive isotopes into the environment.
• Contaminated air, water, and soil, leading to long-term ecological damage.

Chernobyl Disaster

• Explosion released a vast quantity of radioactive materials, affecting Europe.
• Resulted in the creation of a contaminated exclusion zone.

Health Risks from Radioactive Isotopes

• Iodine-131 can concentrate in the thyroid, increasing thyroid cancer risk, particularly in children.
• Cesium-137 can contaminate food sources, leading to long-term health risks and cancers.
• Acute Radiation Syndrome affected many workers at Chernobyl, causing severe health consequences.

Long-term Effects

• Increased rates of thyroid and other cancers in populations exposed in both Fukushima and Chernobyl incidents.

Environmental Impact

• Fukushima caused concerns regarding marine life contamination; cesium found in fish led to fishing restrictions.
• Chernobyl's exclusion zone remains heavily contaminated but is paradoxically allowing some wildlife to thrive due to limited human activity.

Water Properties

• Water exhibits high specific heat, requiring significant energy to change temperature; crucial for homeostasis in organisms.
• High specific heat helps maintain stable environments for aquatic life and allows cooling in plants through evaporation.

Solvent Properties of Water

• Water’s polarity makes it an excellent solvent, crucial for metabolic reactions in cells.
• Almost all biochemical reactions require reactants to be dissolved in water.

Carbohydrates Overview

• Composed of carbon, hydrogen, and oxygen with a basic formula ratio of 1:2:1.
• Monosaccharides, the simplest sugars, are the basic building blocks of carbohydrates.

Monosaccharides Examples

• Glucose: primary energy source for cells and brain; derived from foods.
• Galactose: milk sugar, important for brain and immune system functions.
• Fructose: found in fruits and honey.

Disaccharides

• Formed by condensation reactions, linking two monosaccharides via glycosidic bonds.
• Examples include:
  • Sucrose: glucose + fructose (table sugar).
  • Maltose: glucose + glucose (from hydrolyzed starch).
  • Lactose: glucose + galactose (found in mammalian milk).