College Biology 101 Full Set

Analysis in the Scientific Method

You perform this step of the scientific method when you compare the results of an experiment to the prediction you made in your hypothesis.

Dependent Variable

A scientific variable that will change depending on other variables. In an experiment where you apply water to paper to see what happens, paper is the dependent variable.

Observation in the Scientific Method

Completing this part of the scientific method involves observing any results that occur during your experiment.

Scientific Law

These are scientific statements that are viewed as facts and have yet to be disproven, such as Mendels laws.

Bar Chart

A kind of chart that shows information in proportional rectangular bars. This is useful for comparing amounts.

Independent Variable

The variable in an experiment that won't change based on another variable. If you are testing the response of a plant to fertilizer then the fertilizer is this variable.

Pie Chart

You can use this chart if you want to easily show percentages of a given subject. It consists of a circle divided into different sections.

Conclusion in the Scientific Method

Scientists complete this step in the scientific method when they summarize their findings and state whether or not their initial hypothesis was correct.

Flow Chart

A chart that is useful if you are trying to show relationships and conceptual information. It shows how concepts relate to one another.

Controlled Experiments

This kind of experiment only tests one factor at a given time. In order to conduct this kind of experiment you must make sure that your variables are the same for all subjects being tested.

Scientific Theory

A term used to describe a scientific hypothesis that has been accepted after being tested by multiple scientists who all reach the same conclusion.

Line Graph

This can be used to show relationships between variables but little else. It includes two axes that you can use to represent different variables.

Scientific Method

This term is used to describe the procedures used by scientists when they are working to increase what they know about the world.

Paleozoic Era

Included the Cambrian explosion Reptiles, insects, and more varieties of advanced plant life appeared Era ended with many land and water organisms becoming extinct

Catastrophism

A theory proposed by George Cuvier that describes evolution as a process following local catastrophic events like floods or fires Events would lead to extinction or adaptation

Adaptation

In the context of evolution, it describes organisms as changing.

Carbon-14

The most common element used in radioactive dating of rocks and fossils

Cenozoic Era

Started after the mass extinction of dinosaurs Mammals, birds, and insects became more diverse Humans developed in this time period Current era

Mesozoic Era

Also called the age of the dinosaurs Plant life was mostly limited to gymnosperms, which are flowerless Ended 66 million years ago with a mass extinction of the dinosaurs

Cambrian Explosion

Occurred during the Paleozoic Era Characterized by an enormous increase in organism population and diversity Included life moving from water to land

Status

In the context of evolution, it describes organisms as staying the same. Occurs when organisms are a good fit for their environment

Evolution

An important concept in biology that describes how organisms change over time

Punctuated Equilibrium

A theory that states that life on Earth evolved with periods of brief and abrupt changes followed by long periods of stability.

Precambrian Era

Started when Earth was formed Production of oxygen by single-celled organisms allowed for evolution of more complex, multicellular organisms such as jellyfish and worms

Gradualism

A theory proposed by James Hutton that describes evolution as a long, gradual, continuous process occurring over time Adaptations in organisms appear slowly over many generations

Mass Extinction

An event occurring between eons or eras that kills off a great amount of living organisms

Adaptive Radiation

A theory that states that organisms that share a common ancestor evolved when they radiated (moved) away from one area and adapted to another Example: finches found on Galapagos Islands

Phylogenetic Tree

Scientists use this chart to demonstrate the evolutionary relationships between different organisms. It can show changes related to evolutionary time and amounts of change.

Clade

This term refers to the groups made up of one ancestor and all of that creature's descendants that appear on phylogenetic trees and cladograms.

Postzygotic Barrier

This reproductive barrier works by lowering the ability of hybrid offspring of different organisms to reproduce.

Disruptive Selection

This type of natural selection occurs when organisms change based on negative pressures, such as if a bug eats one specific color of flower, leading to future generations of a different color.

Speciation

This process occurs when one species divides into at least two new species over a period of time. This can only occur if groups of the original species are removed from one another.

Acrosome

This part of a sperm cell acts as a cap and works to penetrate through the ovum's outer layers.

Heritability of Acquired Characteristics Theory

This theory has since been dismissed, but originally it asserted that an organism developed certain characteristics during its lifetime that it could pass to offspring.

Allopatric Speciation

This type of speciation is caused by a physical barrier separating the original species group. It can also be called geographic speciation.

Order of Taxonomic Classification

Kingdom and Phylum Class Order Family Genus and Species

Nondisjunction

This chromosome segregation error occurs when linked homologs, also called chromatids, fail to split apart during anaphase.

Ectoderm

Scientists use this term when referring to the outermost germ layer of cells in early embryos.

Convergent Evolution

This occurs when organisms individually evolve certain traits due to selective pressure, such as birds and bugs evolving wings, or creatures surrounded by water evolving to swim.

Endoderm

This is the innermost germ layer of cells in embryos. This layer will eventually develop into the gastrointestinal tract.

Type I Survivorship Curve

This kind of survivorship curve shows individuals surviving through middle life and then dying as they move to late life.

Oogenesis

the term for the biological process that results in the creation of ova (female gametes)

Clades: Major Types

Monophyletic Paraphyletic Polyphyletic

Sympatric Speciation

This kind of speciation happens even when organisms are still located in close physical proximity.

Polyploidy

This is a characteristic that can allow sympatric speciation. It only occurs in organisms or cells that possess more than two full sets of chromosomes.

Cladogram

This type of chart can help determine how closely related one creature is to another. Organisms that are more closely related should be grouped closer together.

Mesoderm

This is the middle germ layer of early embryo cells.

Type II Survivorship Curve

This type of survivorship curve indicates that a species has a constant mortality rate across its lifespan.

Natural Selection: Major Types

Directional Disruptive Stabilizing

Prezygotic Barrier

a type of barrier that halts reproduction by stopping fertilization from ever occurring

Characteristic shared by prezygotic and postzygotic barriers

Both of these barriers will isolate species.

Colonization

When a species sets up a stable population in an area where it was not already found

Producer

An organism that uses an abiotic source (such as the sun) to obtain its energy. An example is plants.

Intraspecific Competition

When organisms of the same species compete for resources

Ecosystem Ecology

The study of the level of ecology that includes the community plus the abiotic (nonliving) factors of the community

Interspecific competition

Competition for resources between two or more species in the same community

Predator/Prey Interactions

Describes offensive strategies of predators (speed, poison, flight) and defensive strategies of prey (camouflage, chemical warfare, mimicry), which often adapt together through coevolution.

Density-Dependent Factor

A factor affecting a population in an ecosystem that is dependent on the number of organisms in the population. Includes habitat, food, and water.

Trophic Level

The level in a food chain that an organism's energy comes from. For example, the first trophic level contains organisms that get their energy from an abiotic source.

Commensalism

A symbiotic relationship in which one organism benefits while there is no effect on the other. Examples include algae and barnacles on turtles and whales.

Detritivore

An organism that uses dead organic material or waste products as its food source. Examples are vultures, fungi, and bacteria.

Population

A level of ecological organization that includes all the organisms of the same species that live in a specific area.

Biosphere Ecology

The study of the level of ecology that encompasses all of the planet's ecosystems

Density-Independent Factors

A factor affecting a population in an ecosystem that is not dependent on the number of organisms in the population. Includes predation and disease.

Batesian Mimicry

When a harmless or edible organism mimics a harmful or inedible organism. An example is harmless flies or beetles mimicking the yellow and black stripe pattern of hornets.

Local Extinction

When an organism becomes extinct in a specific area

Immigration

A one-time movement of organism(s) into a geographical area

Food Chain

A sequential model that describes how organisms feed on one another

Cerebellum

The part of the human brain located at the back of the head that helps us coordinate our movements and walk. This area of the brain also supports our memory.

Lactic Acid Fermentation

A type of anaerobic cellular respiration that isn't very effective. This kind of respiration can lead to achy muscles later on.

Cellular Respiration

This process allows cells to turn food into energy. It produces water, carbon dioxide and energy.

Types of tissue in the heart

The heart has nervous tissues that guide its beat, epithelial tissues that keep blood in the heart, and connective tissues that connect it to your ribs.

Definition of Organs

A structure that is composed of different kinds of tissues that work with one another in order to complete a task.

Genetic Reassortment

A shift in gene segments that can occur if you get infected with two viruses at the same time. This can result in shifts in antigens that lead to disease outbreaks.

Bronchi

The biological structures that connect the lungs and the trachea, allowing the passage of air into our lungs.

Extracellular Matrix

This term refers to tissues that are found outside of cells.

The role of the mouth in digestion

Digestion begins in this body part as food is chewed and broken down by the enzyme amylase.

Cardiac Muscle Cells

A kind of involuntary muscle cell characterized by the ability to transmit electrical signals that instigate contractions.

Synapse

This junction exists at the end of an axon and is responsible for releasing neurotransmitters such as serotonin to target cells when instructed to by a depolarizing signal.

Epithelial Cells in the Stomach

These cells line the walls of your stomach and secrete mucus, hydrochloric acid and pepsinogen as needed to aid digestion.

Purpose of insulin injections

Individuals use these injections when their bodies don't properly produce the hormone insulin. They may also need injections if their cells are resistant to insulin.

Definition of Organisms

This term refers to individual cells that can grow, reproduce, maintain homeostasis and interact with stimuli.

Germ Theory

A scientific theory that states that infectious organisms, these diseases have to move between hosts to spread. Understanding this theory led to better sanitation when lower deaths due to disease.

Chemoreceptors

Sensory neurons that are stimulated by particular molecules. These neurons are connected to the sense of taste and smell in humans.

Autonomic Nervous System

This part of the human nervous system is responsible for controlling involuntary body functions, such as salivation, breathing, sweating and digestion.

Smooth Muscle Cells

These muscle cells are involuntary and appear throughout the human body, with the exception of the heart. They have no striations.

Definition of Tissues

These cells work together in the same structure while performing the same function in an organism.

Cartilage

This connective tissue provides padding to bones as well as support for our noses and ears.

Bones

A type of connective tissue that gives humans their shape and form.

Acquired Immunity

A type of immunity that occurs when we experience an illness, such as measles, and develop an immune response to it that prevents us from succumbing to the pathogen if we encounter it again.

The role of the esophagus in digestion

This portion of your digestive tract connects your pharynx to your stomach. Blocking this will prevent food from continuing on in the digestive process.

Systemic Circuit

This portion of the circulatory system is responsible for carrying blood through the body and returning the blood to the heart. It delivers nutrients and oxygen and carries waste away.

Body Parts in the Human Excretory System

Liver Renal tubules Urethra

Brainstem

A section of your brain that sits on the top of the spinal cord. It controls autonomic functions such as your heartrate and breathing.

How sodium affects neurons

The ion sodium starts the process of cell depolarization by entering a cell. Depolarization allows neurons to pass signals.

The process for the oxygenation of blood in the lungs

Oxygen dissolves within the alveoli before diffusing first through the cell wall and then into our blood.

The role of villi in digestion

These structures line folds in the small intestine, increasing surface area and allowing for more efficient absorption of nutrients.

Circulatory System

This body system is responsible for moving blood through the human body, thereby delivering oxygen and other nutrients to our cells. It includes the heart and blood vessels.

Live Attenuated Vaccines

These vaccines use living viruses that are still infectious in the vaccine, typically using a less dangerous version of the disease. The smallpox vaccine is an example of this.

Osteocytes

These cells are involved in the process of bone formation. They are capable of secreting calcium phosphate which can harden bones.