Biological Science - Chapter 1: Biology: The Study of Life

Flashcards covering key concepts from Chapter 1 of Biological Science, focusing on the characteristics of life, evolution, and scientific methodology.

What are the five fundamental characteristics shared by all living organisms?

Cells, replication, information processing, energy acquisition and use, and evolution.

What is the central dogma of molecular biology?

DNA to RNA to protein

How does a scientific theory differ from the everyday usage of the word "theory"?

In science, a theory is an explanation for a very general class of phenomena or observations supported by a wide body of evidence, not just speculation or a guess.

Name the three theories that form the framework for modern biological science.

Cell theory, theory of evolution by natural selection, and chromosome theory of inheritance.

What does the cell theory state?

All organisms are made up of cells, and all cells come from preexisting cells.

What is a hypothesis?

A testable statement (i.e. assumption) that explains something observed.

What is the role of experiment in research?

Allows researchers to test a hypothesis utilizing the scientific method

What is the significance of cell replication in the context of life?

Cells must replicate for life to exist. All cells in a multicellular organism have descended from preexisting cells and are connected by a common lineage.

What does evidence suggest about the origin of life on Earth?

Life arose from non-life early in Earth’s history by a process of chemical evolution.

What is the chromosomal theory of inheritance?

Hereditary or genetic information is encoded in genes, which are units located on chromosomes.

What is the role of DNA?

DNA is the hereditary material; genes are segments of DNA that code for cell products.

Who proposed the double helix structure of DNA?

James Watson and Francis Crick (with the help of Rosalind Franklin and Maurice Wilkins).

Which base pairings are present in DNA?

A::T (2 H bonds) and C:::G (3 H bonds)

What is the central dogma of molecular biology?

DNA codes for RNA, which codes for proteins.

Why is DNA replication important?

To pass genetic information from cell to cell or from one organism to its offspring.

What is a mutation?

A permanent change in the DNA sequence that may lead to changes in proteins and heritable variations.

What are the two fundamental nutritional needs of organisms?

Acquiring chemical energy in the form of adenosine triphosphate (ATP) and molecules that can be used as building blocks to make DNA, proteins, lipids, etc.

What is evolution?

Change in the characteristics of a population over time.

What were Darwin and Wallace's two main claims about the natural world?

Species are related by common ancestry, and the characteristics of species can be modified from generation to generation (descent with modification).

Define population, in a biological context.

A group of individuals of the same species living in the same area at the same time.

What are the two conditions necessary for natural selection to occur in a population?

Individuals must vary in characteristics that are heritable, and in a particular environment, certain versions of these heritable traits help individuals reproduce more than other versions.

Explain how natural selection leads to evolutionary change.

Certain heritable traits lead to increased success in producing offspring; these traits become more common in the population over time.

On what level does natural selection act?

Natural selection acts on individuals.

On what level does evolutionary change occur?

Evolutionary change occurs in populations.

Define fitness in the context of natural selection.

The ability of an individual to produce offspring; individuals with high fitness produce many more surviving offspring than others in the population.

What is an adaptation?

A trait that increases the fitness of an individual in a particular environment.

What does the tree of life depict?

Evolutionary history and relationships among species, with a single ancestral species at its base.

What is phylogeny?

A tree diagram showing actual genealogical relationships among all organisms.

How is genetic variation analyzed to determine evolutionary relationships?

By studying RNA and DNA from different organisms and comparing sequences of building blocks (A, T, C, G).

What does a phylogenetic tree show?

The relationships between species, where branches that share a recent common ancestor are closely related.

What are the three major groups (domains) of organisms?

Eukarya (eukaryotes), Bacteria, and Archaea (prokaryotes).

What is taxonomy?

The effort to name and classify organisms.

List the hierarchical classification system from Domain to Species.

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

Who established the classification system still in use today?

Carolus Linnaeus in 1735.

What are the two parts of an organism's species name?

Genus and specific epithet.

What does doing biology mean, in scientific terms?

Asking questions that can be answered by measuring things and collecting data

What does hypothesis testing involve?

Stating a hypothesis precisely, listing predictions it makes, and designing an observational or experimental study to test those predictions.

What important characteristics should a well-designed experiment have?

Inclusion of a control group, constant experimental conditions, repeated testing, and a large sample size.