Biology Lecture Notes: Characteristics of Life, Levels of Organization, Cells, Interactions, and DNA to Proteins

Vocabulary flashcards covering key biology concepts from the lecture notes, including life characteristics, levels of organization, cell types, interactions, and the DNA-to-protein pathway.

Characteristics of life

A set of criteria that living things share, including organization, regulation, energy processing, growth and development, response to the environment, reproduction, and evolutionary adaptation.

Evolutionary adaptation

Gradual changes across generations that make organisms better suited to their environment.

Regulation (homeostasis)

Control of internal processes to maintain stable conditions amid environmental changes.

Energy processing

How living things obtain and use energy.

Growth and development

Increase in size and maturation governed by DNA.

Response to environment

Detection of and reaction to stimuli in the surroundings.

Reproduction

Ability to produce offspring of the same kind.

Organization (Theme of biology)

Hierarchy and classification of life into levels of organization.

Information (Theme of biology)

DNA and its role in transferring genetic information from parent to offspring.

Energy and matter (Theme)

How energy flows through ecosystems and how matter cycles through organisms and the environment.

Interactions (Theme)

How living things depend on and affect one another and their environment.

Evolution (Theme)

Change in species traits over time, reflecting common ancestry.

Reductionism

Approach that breaks complex systems into simpler parts to study them.

Systems biology

An approach that studies biological systems as a whole, focusing on complex interactions between its components rather than isolated parts, to understand emergent properties.

Emergent properties

New traits that arise when parts interact, not present when parts are isolated.

Levels of organization

From molecules to the biosphere: molecule, organelle, cell, tissue, organ, organism, population, community, ecosystem, biome, biosphere.

Molecule

A group of two or more atoms bonded together.

Organelles

Parts of a cell that perform specific functions; in eukaryotic cells, many are membrane-bound.

Cell

Fundamental unit of life.

Tissue

A group of similar cells performing a specific function.

Organ

A body part that carries out a particular function.

Organism

An individual living thing.

Population

A group of the same species living in the same area.

Community

Multiple species living together in a shared environment.

Ecosystem

A community plus the non-living environment with which it interacts.

Biome

A large region characterized by a similar community and environment.

Biosphere

All life on Earth and its surrounding environments.

Eukaryotic cell

A cell with a nucleus and membrane-bound organelles; includes plants, animals, fungi, and protists.

Prokaryotic cell

A cell without a nucleus or membrane-bound organelles; DNA is not enclosed in a nucleus.

Nucleus

Membrane-bound organelle that houses the cell’s genetic material in eukaryotes.

Membrane

A phospholipid bilayer that encloses cells and organelles, acting as a barrier.

DNA (Deoxyribonucleic acid)

Genetic material that stores information in a double-helix structure.

Nucleotides

The monomers that make up DNA and RNA; consist of a sugar, phosphate, and base.

Gene

A specific sequence of nucleotides that codes for a protein.

Protein

A molecule that performs most cellular functions; its shape determines its function.

Double helix

The two long strands of DNA wound around each other.

RNA (Ribonucleic acid)

A molecule that helps transmit genetic information; typically single-stranded and uses ribose sugar.

mRNA (messenger RNA)

RNA copy of a gene that carries instructions from DNA to ribosomes for protein synthesis.

Genome

The complete set of DNA in an organism.

Genomics

The study of genomes, i.e., the entire set of genes in an organism.

Proteomics

The study of the full set of proteins and their properties.

Transcription

The process of copying a DNA sequence into messenger RNA.

Translation

The process by which ribosomes read mRNA and assemble amino acids into a protein.

Photosynthesis (energy flow example)

Process by which plants convert light energy to chemical energy, supporting energy flow through the ecosystem.

Producer

An organism that makes its own food (autotrophs), initiating energy flow in ecosystems.

Consumer

An organism that eats other organisms to obtain energy.

Decomposer

An organism that breaks down dead matter, returning nutrients to the environment.

Negative feedback

A regulatory mechanism that counteracts a change to maintain stability.