all Intro bio cards

Biology

The scientific study of life.

What traits are shared by living things?

Living things have order, need matter and energy, keep a stable inner state, respond, grow, reproduce, and adapt over time.

Cell

The smallest and most basic unit of life.

Unicellular

Made of one cell.

Multicellular

Made of many cells.

Tissue

A group of similar cells that work together.

Organ

A body part made of two or more tissue types that work together.

Organ system

A group of organs that work together.

Organism

One living thing.

Population

Members of the same species living in the same area.

Species

A group of similar organisms that can mate and have fertile young.

Community

All the populations that interact in one area.

Ecosystem

A community and the nonliving world around it.

Biosphere

All parts of Earth where life is found.

Levels of biological organization

Atom, molecule, cell, tissue, organ, organ system, organism, population, species, community, ecosystem, biosphere.

Atom

The smallest unit of an element.

Molecule

Two or more atoms joined together.

Matter

Anything that has mass and takes up space.

Food

Matter that gives an organism building blocks and energy.

Energy

The ability to do work.

Metabolism

All chemical reactions that happen in a cell or body.

Main energy source for most life

The sun.

Photosynthesis

The process that uses sunlight to make food and store chemical energy.

Producers

Organisms that make their own food, often by photosynthesis.

Consumers

Organisms that get energy by eating other organisms.

Decomposers

Organisms that break down dead matter and return nutrients to the ecosystem.

How does energy move through an ecosystem?

Sunlight enters, producers store it, consumers and decomposers use it, and much of it leaves as heat.

How do chemicals move through an ecosystem?

Chemicals cycle between producers, consumers, decomposers, and the environment.

Homeostasis

Keeping the inside of the body within safe limits, such as temperature, water, and acidity.

Response

A change an organism makes after a change in its surroundings.

Stimulus

A change that causes an organism to respond.

Reproduction

The process of making new organisms of the same kind.

How do many single celled organisms reproduce?

They split into two cells.

Fertilization

The joining of an egg and sperm.

Embryo

An early stage of a developing multicellular organism.

Gene

A part of DNA that carries information for a trait.

DNA

The molecule that stores the instructions for life.

Adaptation

An inherited trait that helps an organism live and reproduce in its environment.

Evolution

Change in a population over many generations as adaptations build up.

Why is evolution a core idea in biology?

It explains both the shared traits and the great variety of life.

Evolutionary tree

A picture that shows how groups are related through common ancestors.

Common ancestor

An earlier organism from which two or more groups evolved.

Natural selection

The process in which organisms with helpful inherited traits leave more young, so those traits become more common.

Charles Darwin

A scientist who helped explain natural selection and wrote On the Origin of Species.

Alfred Russel Wallace

A scientist who came to the idea of natural selection on his own at about the same time as Darwin.

On the Origin of Species

Darwin's book that gave facts and ideas that support evolution by natural selection.

What can cause an environment to change?

Living factors and nonliving factors can both cause change.

Reproductive success

How well an organism passes its genes to the next generation by having young that live and reproduce.

How does natural selection lead to evolution?

Helpful inherited traits raise reproductive success and become more common over generations.

Descent with modification

The idea that young come from past organisms but have inherited changes over time.

Hawaiian honeycreepers

Birds that evolved from one finch ancestor and formed many bill types for different foods.

Taxonomy

The science of naming and classifying organisms by set rules.

Systematics

The study and grouping of organisms by their evolutionary links.

Classification order from broadest to most exact

Domain, supergroup, kingdom, phylum, class, order, family, genus, species.

Domain

The broadest and most inclusive group in classification.

Supergroup

A large group used to show major evolutionary links within domain Eukarya.

Kingdom

A large group below domain or supergroup.

Phylum

A group of related classes.

Class

A group of related orders.

Order

A group of related families.

Family

A group of related genera.

Genus

A group of very close species and the first word of a scientific name.

Specific epithet

The second word of a scientific name; it helps name the exact species.

Three domains of life

Bacteria, Archaea, and Eukarya.

Prokaryote

A one celled organism that has no membrane bound nucleus.

Eukaryote

An organism whose cells have a membrane bound nucleus.

Domain Archaea

Prokaryotes that often live in harsh places; they may be like some of the first cells on Earth.

Methanosarcina mazei

An archaeon that makes methane.

Domain Bacteria

Simple prokaryotes with many types of metabolism that are found almost everywhere.

Escherichia coli

A bacterium found in the human gut; its short name is E. coli.

Domain Eukarya

The domain of organisms with eukaryotic cells; members may have one cell or many cells.

Why were eukaryotic supergroups made?

DNA studies showed that protists did not all come from one close line, so six larger groups were used to show their links.

How many eukaryotic supergroups are there?

Six.

Archaeplastida

The supergroup that includes plants and red and green algae.

Chromalveolata

The supergroup that includes dinoflagellates, ciliates, diatoms, golden algae, brown algae, and water molds.

Excavata

The supergroup that includes euglenoids.

Rhizaria

The supergroup that includes foraminiferans and radiolarians.

Amoebozoa

The supergroup that includes amoebas and slime molds.

Opisthokonta

The supergroup that includes animals, fungi, and choanoflagellates.

Four eukaryotic kingdoms

Protists, plants, fungi, and animals.

Protists

A very varied group of eukaryotes; many have one cell, but some have many cells.

What organisms are called protists?

Algae, protozoans, and water molds are common examples.

Euglena

A protist with both plant like and animal like traits.

Kingdom Plantae

Multicellular eukaryotes that use photosynthesis to make food.

Pinus longaeva

The bristlecone pine, one of the oldest living organisms on Earth.

Kingdom Fungi

Eukaryotes such as molds and mushrooms that absorb food and help break down dead matter.

Amanita

A genus of mushroom used as an example of fungi.

Kingdom Animalia

Multicellular eukaryotes that eat and digest food.

Homo sapiens

The scientific name for humans.

Binomial naming

A two word system used to give each species one scientific name.

Pisum sativum

The scientific name for the garden pea; Pisum is the genus and sativum is the specific epithet.

How is a scientific name written?

The genus starts with a capital letter, the specific epithet starts with a small letter, and both words are in italics.

Observation

A fact noticed with the senses or a tool.

Scientific method

A repeatable way to ask a question, test an idea, study data, and form a conclusion.

Basic steps of the scientific method

Observation, hypothesis, prediction, experiment, data, and conclusion. The hypothesis may then be changed and tested again.

Inductive reasoning

Using many small facts to form one wider idea.

Hypothesis

A possible, testable answer for an event or observation.

Prediction

A clear result expected if a hypothesis is right.

Experiment

A planned test of a hypothesis or prediction.

Experimental variable

The one factor that is changed in a fair experiment.