AHSGE Review

J. Pollock

Spring 2007

Classification Systems

Compare the five and six-kingdom classification systems.

5-Kingdom– Monera, Protista, Fungi,

Plantae, Animalia– based on structural

similarity– did not include

archaebacteria

6-Kingdom– Monera, Protista, Fungi,

Plantae, Animalia, Eubacteria

– based on structural similarity

– included archaebacteria– need for additional

kingdom with advancing technology

How is the classification system organized?

Six kingdoms phylum class order family genus species

How do I use a dichotomous key?

A dichotomous key is a tool that allows the user to determine the identity of an organism, given two choices.

It has a serious of highly organized statements organized into couplets.

Both choices are read and compared with the organism being identified.

The process continues until a conclusion is reached. http://students.ed.qut.edu.au/n2364379/MDB377/

DichotomousKeyOutline.html

How are monerans, protists, and fungi beneficial and harmful?

Monerans Protists Fungi

Supply food foraquatic life,

supply oxygen,decompose dead

organisms

First link inaquatic food

chains, produceoxygen, used in

industrialproducts

Decomposers,food source,necessary for

production of beerand bread,antibiotics

Some parasitic Some causediseases, somecause red tides

Damage toplants, allergies,

illness

Why can viruses be classified separate from living things?

Viruses do not carry out cellular functions. They can only reproduce inside a host cell because they

are only a strand of DNA or RNA surrounded by a protein coat.

They have a five stage “life cycle.”– adsorption - attachment to cell– entry - injection into cell– replication - construction of new viral components– assembly - new viruses made– release - host cell splits and new viruses go to new cells

Viruses

How is binomial nomenclature used to name organisms?

Organisms are named using their genus and species names.

The names are italicized and the first word capitalized.

Example: Mycobacterium tuberculosis

What skeletal structures distinguish animals?

Internal/external skeleton Vertebrate/invertebrate (backbone/no

backbone) Type of nervous system

What methods of reproduction distinguish animals?

Sexual/asexual External/internal fertilization (eggs fertilized

inside or outside the mother’s body) Zygote development (stages of development) Opposite sexes

How does body symmetry distinguish organisms?

Lack of symmetry (no central point) Radial symmetry (body parts arranged around

a central point) Bilateral symmetry (left and right mirrored

halves)

What body coverings distinguish organisms?

Skin Shell Feathers Fur Hair Scales

What are different methods of locomotion used by organisms?

Cilia/flagella Pseudopods Wings Legs Fins

Describe protective adaptations of animals.

Exoskeleton – arachnids, insects, crustaceans; protection from organ damage

Internal skeleton - vertebrates; protection from organ damage

Nematocysts – protection from predators Coloring – hiding from predators

How does the theory of evolution explain the nature and diversity of organisms?

Evolution is defined as a change in the genetic makeup of a population or species over time.

Darwin’s theory explains that only the animals that are strong and capable of responding to their environments will survive and reproduce.

The characteristics of the surviving organisms become the most common.

It is believed that all organisms developed from simple organisms with the basic cell design.

What is natural selection?

Natural selection is the process by which populations change in response to their environment as individuals better adapted to the environment leave more offspring.

It is also called survival of the fittest. Species that survive have learned to adapt to the

environment. Habitats present different challenges, so organisms must rise to the challenge.

Species in a certain area result from species that once lived in the area or nearby species.

Natural Selection

What is survival of the fittest?

In a particular environment, some individuals are better suited for survival and so leave more offspring.

Over time, change within species leads to the replacement of old species by new species as less successful species become extinct.

How does geographic isolation occur?

With geographic isolation, groups are physically separated.

Smaller populations are particularly vulnerable. Genetic and phenotypic change occur so that

new species are created.

What evidence in the fossil record shows animal adaptation?

Adaptation is a change in a species over several generations. They are NOT changes in organisms.

Fossils are traces of previously living organisms. Scientists can determine their ages using radioactive dating.

Comparisons can be made between previously living organisms and present organisms to show evolution.

What evidence in the fossil record shows animal adaptation?

Some animals possess vestigial organs (structures homologous to other animals that appear to serve no function).

There are also differences in species that are similar in most other ways to show evolution as a process.