Chapter 1: The Scientific Study of Life

Flashcards reviewing the core concepts of biological organization, life characteristics, taxonomy, domains and kingdoms, and scientific method variables.

What is biology?

Biology is the scientific study of life, encompassing all forms of life and their interactions.

What are the five shared characteristics used to define life?

1. Organization
2. Energy use
3. Maintenance of internal constancy (homeostasis)
4. Reproduction, growth, and development
5. Evolution

In biological organization, what is an atom?

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

The matter that makes up life is organized into _____.

atoms

What is an example of an atom?

(any periodic table element)

Carbon, Oxygen, Iron, etc.

What does atomic theory state?

Atomic theory states that all matter, both living and nonliving, is composed of tiny indivisible particles called atoms.

What is a molecule?

A group of joined atoms, such as DNA or Water.

What is an organelle?

A membrane-bounded structure that has a specific function within a cell, such as a chloroplast.

some cells, but not all cells, are composed of organelles.

What is a cell?

The fundamental unit of life.

ex. leaf cell

all life is composed of cells, although some cells do not have organelles

What is a tissue?

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

ex. epidermis of leaf

What is an organ?

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

ex. leaf

What is an organ system?

Organs connected physically or chemically that function together.

ex. aboveground part of a plant

How is an organism defined?

An organism is a single living individual.

ex. one acacia tree

What is an individual organism?

Single-celled, like bacteria and amoeba

just one cell

and

Multicellular, multiple cells, like sea sponges, moss, mushrooms

Organisms composed or tissues, like jelly fish and certain worms

More complex organisms composed of tissues, organs, organ systems. like fish, humans, trees

What is a population?

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

ex. multiple acacia trees

What is a community?

All populations that occupy the same region.

ex. populations in a savanna.

What is an ecosystem?

The living and nonliving components of an area.

ex. the savanna

What is the biosphere?

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

What is metabolism? and its purpose?

The collection of all chemical reactions inside a cell that sustain life by allowing organisms to acquire and use energy and nutrients.

purpose: to build new structures, repair old ones and reproduce

How do producers obtain energy and nutrients?

Producers extract energy and nutrients from the nonliving environment.

What are the 3 broad categories that biologist divide organisms into based on their source of energy and raw materials?

Producers, Consumers, and Decomposers

How do consumers obtain energy and nutrients?

Consumers obtain energy and nutrients by eating other organisms.

What are decomposers?

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

What is homeostasis?

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

ex. shivering when your body is cold, sweating when your body is hot to regulate temperature.

How do asexual and sexual reproduction differ in terms of genetic material?

In asexual reproduction, genetic information comes from one parent and offspring are virtually identical.

ex. strawberries, are identical to parent strawberry

In sexual reproduction, genetic material from two parents unites to form offspring with a new combination of inherited traits.

Genetic diversity ehance the chances that some individuals wills survive even if conditions change

What is biological evolution?

Evolution is genetic change in a population over multiple generations.

What is natural selection?

A mechanism of evolution where individuals with favorable traits survive, reproduce, and pass their genes on to the next generation.

What are the taxonomic groups for human classification from most inclusive to least inclusive?

Domain: Eukarya

Kingdom: Animalia

Species: sapiens

What are the three main domains of life?

Domain Bacteria, Domain Archaea, and Domain Eukarya.

What are the primary characteristics of organisms in Domain Bacteria and Domain Archaea?

They consist of small, prokaryotic cells that lack nuclei, and most are unicellular.

What is the key cellular difference between prokaryotes and eukaryotes?

Eukaryotic cells contain nuclei, whereas prokaryotic cells never have nuclei.

What are the primary characteristics of Kingdom Plantae?

Multicellular autotrophs that produce their own food by capturing light energy from the sun.

Do Eukaryotic cells have nuclei?

yes

What are the primary characteristics of Kingdom Animalia?

Multicellular heterotrophs that obtain energy by ingestion of food.

What are the primary characteristics of Kingdom Fungi?

Heterotrophs that obtain nutrients by external digestion through secretions of digestive enzymes; most are multicellular, though some are unicellular.

What are the primary characteristics of Kingdom Protista?

The most diverse group of eukaryotes, containing unicellular or multicellular organisms that can be autotrophs or heterotrophs.

How do hypotheses and scientific theories differ?

A hypothesis is a testable initial explanation for one or more observations, whereas a scientific theory is a well-tested and supported concept.

how do scientists test their hypothesis?

Discovery science or controlled experiments

What is the difference between qualitative and quantitative data?

Qualitative data is non-numerical (categorical) measuring qualities like color change, whereas quantitative data is numerical measuring values or counts expressed as numbers.

What are independent, dependent, and standardized variables in an experiment?

The independent variable is manipulated by the experimenter, the dependent variable is measured as the response, and standardized variables are held constant across all experimental groups.

What is the difference between a negative control and a positive control?

A negative control is an untreated group not expected to produce results, while a positive control receives a treatment with a known result expected to show a specific change.

What is the experimental control used in scientific experiments purpose?

to prevent factors other than those being studied from affecting the outcome and to provide basis for comparison in measuring the effect of the independent variable.