Biology-Diversity of Living Things

Species concepts

Various definitions of species

Morphological species concept

Focuses on body shape, size, and other structural features

Biological species concept

Defines species based on whether two organisms can produce fertile offspring

Phylogenetic species concept

Examines the phylogeny, or evolutionary history, of organisms

Morphology

Branch of biology that deals with structure or form of organisms

Phylogeny

Evolutionary history of species

Taxonomy

Branch of biology that identifies, names, and classifies species based on natural features

Binomial nomenclature

The system for naming species- two part name

Genus

1st word of Latin name, very broad- closely related species

2nd word of Latin name (binomial nomenclature)

Identifies the specific species

Hierarchical classification

The method for classifying organisms in which species are arranged in categories from most general to most specific

Un-nested classification

A way of classification

Nested classification

A detailed way of classification

Taxonomic categories

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

Non-living species

Virus, can’t reproduce on their own- needs a host

Domains

1. Bacteria

2. Archaea

3. Eukarya

Traditional eukaryotic kingdoms

Protista, fungi, plantae, animalia

Kingdom

• Fewer species than domains

1. Protista

2. Fungi

3. Plantae

4. Animalia

Phylum

Groups together related classes with similar basic characteristics

Class

A group within a phylum

Example: mammals, reptiles, amphibians, birds, fish

Order

Groups together related family

Example: cats are in the order Carnivora

Family

Group of closely related species

Example: felidae → cats, including lions, tigers, and domestic cats

Genus

A group of very similar species

Example: panthera → lions, tigers, leopards, etc.

Species

A group of similar organism that can reproduce with each other

Material of cell wall in plants

Cellulose- a type of carb

Material of cell wall in fungi

Chitin

Material of cell wall in bacteria

Peptidoglycan- made of proteins and carbs

Autotroph meaning

Auto → self, troph → nutrition

Autotroph

Organisms that obtain energy by creating their own food:

1. Photo autotrophs

2. Chemoautotrophs

Photo autotrophs examples and meaning

Photo → plant, autotroph → self nutrition

1. Plants

2. Algae

3. Photosynthetic bacteria

Heterotrophs

Must consume other organisms to obtain energy-yielding food

Asexual reproduction

Reproduction that involves only one parent and produces offspring that are genetically identical or nearly identical to the parent

Anatomical evidence

Compares structure and form of organisms, including bones, to identify/classify species

Physiological evidence

Compares the biochemistry of organisms, including proteins, to identify/classify species

DNA evidence

Compares organisms’ DNA sequences to identify/classify species

Prokaryotic cells

• Don’t have a membrane bound nucleus

• Don’t have organelles

• Reproduces through binary fission

• Unicellular

• Very small

• Word means “before the nucleus”

Eukaryotic cells

• Have a membrane bound nucleus

• Have organelles

• Reproduces through mitosis/meiosis

• Mostly multicellular

• Around 1000x larger than prokaryotic cell

• Word means “true nucleus”

Dichotomous keys

Another tool to identify individuals or species

Species diversity

The variety and abundance of species in a given area

Genetic diversity

The variety and abundance of genes (/inherited traits) within a certain species

Ecosystem diversity

Rich diversity oof ecosystems found on earth, each of which contains many species

Gene pool

Genetic diversity within a population

Genetic diversity is important for _____________

Disease resistance. Populations that lack genetic diversity are more likely to have disease than those with high diversity

Abiotic factors

Altitude, latitude, geology, soil nutrients, climate, light levels, etc.

Biotic factors

Interacting populations of species

i.e.- humans, animals, plants, etc

Cellular Respiration

C6H1206 + O2 —> CO2 + H2O + 36ATP

Viruses

A structure that contains DNA or RNA surrounded by a protective protein coat; it can’t live independently outside of cells

Typical Virus structure

No cytoplasm, no membrane bound organelles, no cell membrane

Which virus is this?

Polio

Which virus is this?

HIV

Which virus is this?

Tobacco Mosaic Virus

Which virus is this?

T4 (only for bacteria)

Capsid

DNA or RNA of a virus

Lytic cycle

Virus replication cycle in which a virus infects a host cell, uses it to make new viruses, and then causes the cell to burst (lyse), releasing the new viruses

Lysogenic cycle

Viral DNA enters and becomes a part of the host cell’s chromosomes (then referred to as a provirus)

Provirus

A virus genome that has integrated itself into the DNA of a host cell

Genome

Complete set of genetic information (DNA) in an organism