Key concepts Flashcards
What are elements, and what role do they play in the universe?
Elements are fundamental substances from which all matter is composed. They form the basis of everything in the universe, including our bodies.
Give examples of elements commonly found in the universe.
Examples include sodium (Na), chlorine (Cl), hydrogen (H), and oxygen (O).
What is an atom, and how does it relate to elements?
An atom is the smallest unit of an element that retains its chemical properties.
What are the major elements found in the human body, and what percentage do they make up?
Carbon (C), oxygen (O), hydrogen (H), and nitrogen (N) make up approximately 95% of the body’s mass.
Why are calcium (Ca) and phosphorus (P) important for the body?
They are major components of bone, providing strength and structure.
Describe the structure of an atom.
An atom consists of a nucleus containing protons and neutrons, surrounded by electrons in an electron cloud.
How do ions play a role in the body’s function?
Ions dissolve in water to form electrolytes, which are essential for bodily functions like nerve transmission and muscle contraction.
Differentiate between protons, neutrons, and electrons.
Protons carry a positive charge, neutrons have no charge, and electrons carry a negative charge.
What is the significance of the atomic number?
The atomic number represents the number of protons in an atom, defining its identity as an element.
Explain the body’s connection to atoms and ions.
The body relies on atoms and ions for various physiological processes, including cellular communication and muscle contraction.
Define a chemical compound and give examples.
A chemical compound is formed by combining elements through chemical bonds. Examples include water (H2O) and salt (NaCl).
What are ionic bonds, and how do they form?
Ionic bonds are formed by the attraction between positively and negatively charged ions. They result from the transfer of electrons between atoms.
Differentiate between acids and bases.
Acids release hydrogen ions (H+) in solution, while bases release hydroxide ions (OH-).
Explain the significance of the pH scale.
The pH scale measures the acidity or alkalinity of a solution, with values below 7 indicating acidity, 7 neutrality, and above 7 alkalinity.
How do buffers help maintain pH stability in the body?
Buffers resist changes in pH by accepting or donating hydrogen ions, helping to maintain homeostasis.