Biological Sciences Review

These flashcards cover key concepts in biological sciences, including definitions, differences between cellular structures, and processes relevant to evolution and molecular biology.

What are the independent and dependent variables in a scientific experiment?

The independent variable is the one that changes, while the dependent variable is the one that’s being measured based on the independent variable.

What are the three domains of life on Earth?

Bacteria, Archaea, Eukarya.

How do prokaryotic and eukaryotic cells differ?

Prokaryotic cells are smaller, unicellular, and do not have membrane-bound organelles; eukaryotic cells are larger, can be uni or multicellular, and have membrane-bound organelles.

Define evolution.

Evolution is the process of DNA of living organisms changing over time for better environmental adaptation.

What is natural selection?

Natural selection is the mechanism of evolution that chooses animals that can survive and reproduce the best, allowing adaptive traits to be passed down.

What is an adaptation in biological terms?

An adaptation is a beneficial trait that evolves in response to environmental changes.

What do acquired traits and heritable traits refer to?

Acquired traits are developed from lifestyle or environment, while heritable traits are those derived from an organism's DNA.

What are the parts of an atom?

An atom consists of a nucleus containing protons and neutrons, with electrons orbiting around the nucleus.

What distinguishes polar molecules from nonpolar molecules?

Polar molecules have positive and negative ends, while nonpolar molecules have a neutral charge distribution.

What is the pH scale?

The pH scale measures the degree of acidity in a solution.

What is cellulose and why is it important?

Cellulose is a polysaccharide that comprises plant cell walls and provides structural support; it's important as it gives plants high tensile strength.

What happens when a protein is denatured?

When a protein is denatured, it loses its specific shape and becomes non-functional due to extreme heat, pH changes, or salt concentration changes.

What are the four types of biological molecules?

Carbohydrates, Proteins, Lipids, and Nucleic Acids.

What is the primary structure of a protein?

The primary structure is the amino acid sequence held together by peptide bonds.

Describe the secondary structure of proteins.

The secondary structure is the helix or pleated structure of a polypeptide chain caused by hydrogen bonds.

What are the monomers of nucleic acids?

Nucleotides.

What is the function of polysaccharides?

Polysaccharides provide long-term energy storage.