Chapter 6 life science


Terms in this set (...)


-Species are a group of animals.
is a group of organisms that share similar characteristics and can reproduce among themselves to produce fertile offspring.
-Evolution is a key part of our world.
Many characteristics of a species are inherited when they pass from parent to offspring. Change in these inher- ited characteristics over time
Natural selection

-Natural selection is what come natural to an animal
means that organisms with traits best suited to their environment are more likely to survive and reproduce.

- variation is common everywhere.
is an inherited trait that makes an individual different from other members of its species.

- Adaptation is when animals change to adjust.
is any variation that makes an organism better suited to its environment.

- Gradualism is a very slow process
The model that describes evolution as a slow, ongoing process by which one species changes to a new species
punctuated equilibrium

- Punctuated equilibrium isn't consistent.
model, rapid evolution comes about when the mutation of a few genes results in the appearance of a new species over a relatively short period of time.
Acquired characteristics

In America the theory of Acquired characteristics was proven incorrect.
In 1809, Jean Baptiste de Lamarck proposed a hypothesis to explain how species change over time. He suggested that characteristics, or traits, developed during a parent organism's lifetime are inher- ited by its offspring.
geographic isolation

- Geographic isolation is like an island in the middle of the ocean.
Sometimes mountains, lakes, or other geologic features isolate a small number of individuals from the rest of a population.
changes in genes

-Changes in genes makes the appearance different.
Overtime,thegenetic makeup of a species might change its appearance.

-Darwin discovered amazing things.
In December 1831, the HMS Beagle sailed from England on a journey to explore the South American coast. On board was a young naturalist named Charles Darwin. During the journey, Darwin recorded observations about the plants and animals he saw. He was amazed by the variety of life on the Galápagos Islands, which are about 1,000 km from the coast of Ecuador.

-Lamarck Hypothesis changed the look of the animals in the world.
Lamarck proposed a hypothesis to explain how species change over time.
sedimentary rock
- sedimentary rock are cool looking especially in the grand canyon.
formed when layers of sand, silt, clay, or mud are compacted and cemented together, or when minerals are deposited from a solution.
relative dating
-relative dating is like assuming the time/ age it came from.
Method of determining the age of a fossil by comparing its placement with that of fossils in other layers of rock
radiometric dating
-radiometric dating is different than relative dating.
Dating using decay of radioactive isotopes.
radioactive element
-radioactive element is a steady amount of radiation.
gives off a steady amount of radi-
ation as it slowly changes to a nonradioactive element.
-The study of fossils have shown the evolution that has happened since the olden days.
Preserved remains of once-living organisms
-embryology is amazing feature to life.
the study of embryos and their development
Homologous structures
-Homologous structures are similar like bat wing and human hands.
body parts that are similar in origin and structure
vestigial structures
-Vestigial structures are useless
structures that don't seem to have a function.
-Dna is like a latter
the molecule that controls heredity and
directs the development of every organism.
In a cell with a nucleus, DNA is found in
genes that make up the chromosomes.