Introduction to Biology, Life Processes, and Cellular Energetics

Vocabulary practice flashcards covering definitions of life, chemical solutions, photosynthesis, cellular respiration, and the MRS GREN life processes.

Natural science

A branch of science developed from philosophy that focuses on performing experiments and collecting data.

Biology

The branch of science that studies life and living things.

Old definition of life

The historical definition stating that life is anything that is born, grows, reproduces, and dies; discarded because non-living crystals also perform these actions.

Solute

The substance in a solution that is present in the lesser proportion.

Solvent

The substance in a solution that is present in the greater proportion (in biological systems, this is always water).

Saturated solution

A solution that contains so much solute that no additional solute can dissolve in the solvent.

Anaerobic organisms

Living things that do not breathe; these were the first organisms to exist on Earth.

Modern definition of life

A metabolic definition stating that life is anything that eats, acquires matter and energy from food, and excretes waste.

Matter (in living systems)

Substances required for cell growth and tissue repair that continuously cycle and are recycled infinitely without needing an external supply.

Energy (in living systems)

A non-cycling necessity for all vital processes that flows through living bodies, cannot accumulate, and is permanently lost as heat.

The Sun

The ultimate source of energy required for all living processes and life on Earth.

Photosynthesis

The chemical reaction that harnesses energy from sunlight and packages it into glucose molecules, releasing oxygen as a waste product.

Photosynthesis chemical equation

$$CO_2 + H_2O \rightarrow C_6H_{12}O_6 + O_2$$

Reactants

The starting substances located to the left of the arrow in a chemical equation.

Products

The resulting substances located to the right of the arrow in a chemical equation.

Coheficient

The large number or letter placed before a chemical symbol or formula in an equation.

Subindex

The small subscript number written to the lower right of an element symbol indicating the number of atoms.

Respiration

The chemical process of breaking down food molecules (glucose) to release usable energy ($\text{ATP}$) for living processes.

Respiration chemical equation

$$C_6H_{12}O_6 + O_2 \rightarrow CO_2 + H_2O + \text{ATP}$$

Oxidation reactions

Any chemical reactions that require oxygen to occur.

ATP (Adenosine Tri Phosphate)

The primary energy-containing molecule of the cell, composed of adenine, ribose, and three phosphate groups.

Autotrophs (Producers)

Organisms, specifically plants, that synthesize their own food and form the beginning of every trophic chain.

MRS GREN

An acronym representing the seven essential processes of living organisms: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, and Nutrition.

Movement

The life process involving a change of place; not performed by all living things (e.g., plants and coral).

Sensitivity

The life process of detecting changes in the external or internal environment and responding to them.

Growth

The life process characterized by an increase in size through cell enlargement, cell division, or both.

Reproduction

The life process of generating new organisms of the same species.

Excretion

The life process of removing metabolic waste products from the body after absorbing nutrients.

Nutrition

The life process of acquiring and absorbing nutrients from food.