BIO 101-Chapter 1: The Scientific Study of Life

the five characteristics of life

(1) Organization, (2) energy use, (3) maintenance of internal constancy, (4) reproduction, growth, and development, (5) evolution

organization

Atoms make up molecules, which make up cells, which make up tissues, and so on. One of the five characteristics of life.

energy use

A kitten uses the energy from its mother's milk to fuel its own growth. One of the five characteristics of life.

maintenance of internal constancy

Your kidneys regulate your body's water balance by adjusting the concentration of your urine. One of the five characteristics of life.

reproduction, growth and development

An acorn germinates, develops into an oak seedling, and, at maturity, reproduces sexually to produce its own acorns. One of the five characteristics of life.

evolution

A change in the genetic makeup of a population over multiple generations. Increasing numbers of bacteria survive treatment with antibiotic drugs. One of the five characteristics of life.

atom

The smallest chemical unit of a type of pure substance (element).

molecule

A group of joined atoms.

organelle

A membrane-bounded structure that has a specific function within a cell.

cell

The fundamental unit of life.

tissue

A collection of specialized cells that function in a coordinated fashion.

organ

A structure consisting of tissues organized to interact and carry out specific functions.

organ system

Organs connected physically or chemically that function together.

organism

A single living individual.

population

A group of the same species of organism living in the same place and time.

community

All populations that occupy the same region.

ecosystem

The living and nonliving components of an area.

biosphere

The global ecosystem; the part of the planet and its atmosphere where life is possible.

emergent properties

arise from interactions among the parts that make up an organism.

producers

Make their own food by extracting energy and nutrients from the nonliving environment. Also called autotrophs.

consumers

Obtain energy and nutrients by eating other organisms, living or dead. Also called heterotrophs.

decomposers

are consumers that obtain nutrients from dead organisms and organic wastes.

homeostasis

process by which a cell or organism maintains a state of internal constancy or equilibrium.

asexual reproduction

genetic information comes from only one parent and all offspring are virtually identical.

sexual reproduction

genetic material from two parent individuals unites to form an offspring, which has a new combination of inherited traits. By mixing genes at each generation, this results in tremendous diversity in population.

adaptation

An inherited characteristic or behavior that enables an organism to survive and reproduce successfully in it's environment.

natural selection

The enhanced reproductive success of certain individuals from a population based on inherited characteristics.

Charles Darwin

1809-1882 English naturalist and scientist whose theory of evolution through natural selection was first published in 'On The Origin of the Species" in 1859.

Alfred Russel Wallace

(1823-1913) English naturalist who proposed, independently of Charles Darwin, the concept of natural selection as a mechanism for evolution and as a way to explain the great variety of living things.

On the Origin of Species

Darwin's book published in 1859 that presented evidence and proposed a mechanism for evolution that he called natural selection.

taxonomy

The biological science of naming and classifying organisms.

species

The basic unit of classification which designates a distinctive "type" of organisms.

genus

A group of closely related species.

domains

The broadest taxonomic category consisting of: Bacteria, Archaea, and Eukarya.

kingdoms

A subdivision of domains.

the scientific method

A general way of using evidence to answer questions and test ideas.

hypothesis

A tentative explanation for one or more observations.

peer review

Evaluation of scientific results by experts before publication in a journal.

experiment

An investigation carried out in controlled conditions.

sample size

The number of individuals that the scientist will study in an experiment.

variable

A changeable element of an experiment.

independent variable

The variable in an experiment that is manipulated by the investigator to determine whether it influences some other phenomenon.

dependent variable

The response that the investigator measures.

standardized variable

Anything that the investigator holds constant for all subjects in the experiment, ensuring the best chance of detecting the effect of the independent variable.

control

Untreated group used as a basis for comparison with a treated group in an experiment.

placebo

An inert substance that resembles the treatment given to the experimental group.

double-blind

Type of experiment in which neither participants nor researchers know which subjects received a placebo and which receive the treatment being evaluated.

statistical significance

The probability that the results arose purely by chance.

theory

Well supported scientific explanation.