Classification of cells

Cell

Small, membrane enclosed unit of life built with macromolecules that retains each characteristic of life; responsiveness, growth and reproduction, metabolism, homeostasis, and organization

Uniformity and diversity of cells

• exhibit different structures and functions

• Share a basic chemistry

• All descend from a previous cell

• Genome dictates cell structure, function, and behavior

Prokaryotic cell characteristics

• small and simple

• Most abundant

• Bacteria and archaea

• No nucleus

• DNA in circular plasmids

• No membrane bound organelles

Eukaryotic cell characteristics

• large and complex

• Single and multicellular

• Plant, animal, and fungal

• DNA stored in nucleus

• Specialized organelles

Prokaryote and eukaryote similarities

• macromolecules

• Plasma membrane

• Cytosol

• Chromosomes

• Ribosomes

• Unicellular

Prokaryote cell wall

Semi-rigid peptidoglycan layer that gives shape, attachment for flagella and prevents rupture

Prokaryote glycocalyx

Gel-like sugar-protein coating that can protect against immune attack

Chromosomes in prokaryotes

Are circular DNA molecules called plasmids

Cocci

Prokaryotic spherical shape cell (streptococcus)

Bacilli

Prokaryotic rod-shaped shaped cell (E.coli, salmonella)

Spirilla and Vibrio

Prokaryotic spiral shaped cells (treponema pallidum)

Do plants have chloroplasts or mitochondria or both?

Both

Do animals have chloroplasts or mitochondria or both?

Mitochondria

Do fungi have chloroplasts or mitochondria or both?

Mitochondria

Eukaryotic cell DNA

Is contained in a nucleus surrounded by a nuclear envelope and other membrane bound organelles that allow the cell to perform complex functions

Animalia characteristics

• Eukaryotic

• multicellular

• Heterotrophic: consume nutrients from their environment

• Motility

• No regular shape to cells and can change shape

Plantae characteristics

• Eukaryotic

• photosynthesis: convert light energy to chemical energy

• Autotrophic: use inorganic materials and sunlight to generate energy

• Cell wall: made of cellulose to maintain shape and prevent excessive water uptake

• Specialized organelles: plastids, central vacuole, chloroplasts

Fungi characteristics

• eukaryotic

• Multicellular or unicellular chemoheterotrophs

• Chitin: glucose derivative present in cell walls

• Saprotrophic: externally digest and then absorb nutrients from decaying matter

Protista characteristics

• eukaryotic

• Colonies

• Heterotrophic and autotrophic

• Protozoa, unicellular algae, slime molds

Virus

Non-living infectious microbes that only replicate within a host cell

Virus structure

• genetic material (DNA or RNA)

• Capsid: protein coat enclosing genome with differing structures

• Viral envelope: membrane that surrounds capsid and help to infect host