Elements and Chemical Bonds in Biology

These flashcards cover essential concepts related to elements, chemical bonds, pH, and their significance in biology. They are designed for quick review and memorization to aid in exam preparation.

What are the six most important elements essential for life?

Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulfur (CHNOPS)

What is the atomic number and symbol of Hydrogen?

1, H

What is the atomic weight of Oxygen?

16.00

How many protons does Carbon-12 contain?

6 protons

What defines an isotope?

Atoms of the same element with the same number of protons but a different number of neutrons.

What is the primary charge of a neutron?

Neutral

What type of bond forms when atoms borrow electrons?

Ionic bond

What molecule is formed from covalently bonded Hydrogen and Oxygen?

Water (H₂O)

What is the pH range of most biological fluids?

6-8

What is a solution made up of?

A solvent and one or more solutes.

What is the chemical formula for Methane?

CH₄

What is an example of a trace element in the human body?

Iron (Fe)

What happens in a chemical reaction?

Molecules form and break bonds.

What is the role of buffers in biological systems?

Buffers minimize changes in pH by maintaining [H+] and [OH-] levels.

What happens to pH as the concentration of hydrogen ions increases?

The pH decreases, indicating increased acidity.

What does a pH of 7 indicate?

Neutral solution.

What is the atomic mass of Gold (Au)?

196.967

What is the common charge of a proton?

Positive electrical charge.

How do covalent bonds form between atoms?

Atoms share electrons.

What is the percentage of body mass contributed by Oxygen?

65.0%

How are Sodium (Na) and Chlorine (Cl) involved in Ionic bonding?

Sodium donates an electron to Chlorine, forming Na+ and Cl- ions.

How many electrons can the outer shell of a Carbon atom hold?

4 electrons.

What type of bond creates molecules such as H₂ and O₂?

Covalent bond.

Which element is fifth most abundant in the human body?

Calcium (Ca) at 1.5%.

What happens during a chemical reaction regarding reactants and products?

Reactants undergo a transformation to become products.

What is an example of a polar covalent bond?

The bond in a water molecule (H₂O).

What is the primary function of Calcium in biological organisms?

Structural support and signaling.

How does heat capacity relate to water?

Water can absorb a lot of heat before changing temperature.

What does the term 'pH' stand for?

Potential of Hydrogen.

In which series can Lanthanum (La) be found?

Lanthanide series.

What is the chemical formula for Hydroxide ion?

OH-.

What charge does an electron carry?

Negative electrical charge.

What is one property of water that allows it to support life?

Cohesion and adhesion.