Introduction to General Zoology

Zoology

is a branch of biology that deals with the study of animals.

Aristotle

• Greek scientist and philosopher

• Living things: plants (do not move) and animals (can move)

• Animals on their habitat: live in water, land, air could fly

• Plants on their size and pattern of growth: shrubs, trees, and herbs

Carolus Linnaeus

• Swedish taxonomist

• Linnaen System of Classification

• Two main groups: Kingdom Animalia and Kingdom Plantae

Species

• living organisms with similar and specific traits into the same group and called ____

• the basic taxon or unit of classification in the Linnaean System of Classification

• Group of interbreeding natural populations reproductively isolated from other such groups.

• They share common characteristics and can interbreed to produce fertile offspring.

Genus

placed similar species into larger groups

Taxonomy

• scientific field designed to produce a system of classification of the biological resources that exist in the world.

• this best reflects the totality of their similarities and differences.

• It is the science of naming classifying organisms.

Linnaean System of Classification

• classifies organisms based on their physical and structural similarities

• hierarchy - a multi-level scale (kingdom, phylum, class, order, family, genus, and species)

Taxon

• The object in a classification system is called a

The Artificial System

is one the most popular and convenient type of classification used by most taxonomists.

• Based on few character traits only.

• Not predictive of the existing relationship among organisms since no genetic or molecular similarities are considered.

• Animals can be grouped directly using a single trait like the presence or absence of a tail.

• This can be confusing because some cats, like the Manx cat, do not have tails, but they still fall under the class Felidae.

Natural System

is based on a greater number of similarities and is more predictive.

• It groups phylogenetically closely related organisms and takes into account the molecular and genetic relationships of the organisms.

• Today, a more reliable and scientific approach is employed in identifying organisms. (chromosomal, immunological, and deoxyribonucleid acid (DNA) sequence approaches.

• Computer programs are also used to assess the results, making easy and fast identification.

Domains

Taxonomic hierarchy could be demonstrated by starting with the super ___ of life - the highest grouping of organisms.

Eukaryota

All eukaryotic organisms (plants and animals) fall under the domain of

Bacteria

True bacteria fall under the domain of

Archea

is composed of the extremophilic groups of bacteria (can survive in extreme conditions and environments)

Flagellates

• are unicellular microorganisms (no nucleus and asexual reproduction) and are a part of the protozoa group

• characterized by having one or more ___, a hair-like whip organelle and very distinguishable

Fungi

• are more closely related to animals than plants

• the largest organisms on earth (Armillaria Ostoyae)

Kingdom

is the largest unit in the system of classsification. This is divided into phyla (singular, phylum) in the animal kingdom.

Animalia, Plantae, Fungi, Protista and Monera

Five-Kingdom System

Animalia, Plantae, Protista, Fungi, Eubacteria, and Archaebacteria.

Six-Kingdom System:

Animalia, Plantae, Fungi, Protista, Chromista, Archaezoa, Eubacteria, Archaebacteria

• The latest number of kingdoms, as proposed, ____

• Eight-kingdom system

DNA Analysis

Comparing genetic material (DNA or RNA) to determine evolutionary relationships.

Protein Sequencing

Studying amino acid sequences to find similarities between species.

Molecular Clocks

Estimating the time of divergence between species based on genetic mutations.

Fossilized Biomolecules

Extracting ancient proteins, lipids, or DNA from fossils to compare with modern species.

Binomial System

• The scientific name is composed of two words, the genus name and the species name. This is called the ____ of naming organisms

• Names are in Latin.

• An example of this is the scientific name for lion, Panthera leo Lin, wherein Lin stands for Linnaeus. The genus name is Panthera and the species name is leo.

4 months old

• Cats can become pregnant as early as ___.

• Reproductive cycle called “induced ovulation”, a female cat will only ovulate (release eggs) after mating. = changes of pregnancy are high.

Budding or Regeneration

Some animals (starfish and hydra) reproduce asexually through processes like ____, where a part of their body grows into a whole new organisms.

External fertilization

Frogs engages in ____ making the female lay her eggs in water, and the male fertilizes them outside her body.

water, land, air could fly

classification of animals based on their habitat

shrubs, trees, herbs

classification of plants based on their size and pattern of growth