biology unit 1

Biodiversity

fers to the variety and abundance of life on Earth. This includes all plants, animals, and microorganisms, as well as the habitats in which they live.

Ecosystems Diversity

The variety of ecosystems in the biosphere

Ex: forest

Genetic Diversity

- The variety of heritable characteristics (genes) in a population of interbreeding individuals

- Ex: Sugar content in blueberries

importance of classification and taxonomy

- To accurately & uniformly names organisms

- To prevent duplicate names (all names must be approved by International Naming Congresses)

- To prevent misnomers (ie. starfish & jellyfish aren't actually fish)

- To use the same language for all names (Latin)

- To show evolutionary relationships

Species Diversity

The variety and abundance of species in a given area

Ex: 100 species in a coral reef

Binomial Nomenclature

First word genus name (capitalized)

Second word species name (lowercase)

Italicized when typed, underlined when written out

morphological species concept

- define organisms based on morphology (structure, size, body shape)

phylogenetic species concept

- Examines organisms' evolutionary history through DNA analysis

- Species are cluster of organisms that have a relationship, and are different from other organism clusters

- Two separate organisms sharing a common ancestor (evolutionary history) means they're two different species

Different taxonomic ranks

Dear King Pablo Can Only Eat Blue Strawberries

Domain

Kingdom

Phylum

Class

Order

Family

Genus

Species

Prokaryotes vs Eukaryotes:

Prokaryotes Structure and Function

- No nucleus

-No membrane-bound organelles

- Live in extreme environments

- Unicellular

- Single chromosome genome

- Asexual

- not by mitosis or meiosis

- plasmid (circular DNA)

- cell membrane only

- Ex: Streptococcus

Prokaryotes vs Eukaryotes:

Eukaryotes Structure and Function

- Nucleus

- Membrane bound organelles

- Live in temperate environments

- Multicellular

- Several chromosome genome

- Sexual

- by mitosis or meiosis

- Ex: Homo sapiens

Prokaryotes vs Eukaryotes: Similarities

- ribosomes

- genetic material

- cytoplasm

- plasma membranes

- DNA and RNA

example of harmful bacteria

Botulism

cause food poisoning

example of helpful bacteria

- Bacteria fermentation

- help break down food in intestines

characteristics of viruses

- lack organelles and a cell membrane

- cannot carry out metabolic functions

- Don't reproduce on their own, need a host cell

what are vaccines

substance that stimulates the body's own immune system response against invasion of microbes

characteristics of vaccines

- made from weakened form of the virus itself

- triggers the body's immune system to produce antibodies

- memory cells "remember" the virus so future attacks can be prevented

why vaccines are important

- provide immunity

- reduce risk of getting infections

lytic vs. lysogenic cycles

LYTIC CYCLE

- short incubation period

lytic vs. lysogenic cycles

LYSOGENIC CYCLE

longer incubation period

endosymbiotic theory

theory that eukaryotic organisms developed by combining 2 or more simpler cells, possibly prokaryote-like ones.

evidence of endosymbiotic theory

1) similar membranes

2) reproduce by binary fission

3) each contain a circular chromosome

4) Similar DNA to modern-day prokaryotes

5) Ribosomes in these organelles are more similar to prokaryotic ribosomes than to ribosomes elsewhere in the eukaryotic cells.

endosymbiosis process

1. Start with two independent bacteria

2. One bacterium engulfs the other

3. One bacterium now lives inside the other

4. Both bacteria benefit from the arrangement

5. The internal bacteria are passed on from generation to generation

why viruses are not included in our classification system

- don't match with any of the kingdoms in the three domain classification system

- aren't living things

parts of virus

- inner core: nucleic acid (DNA or RNA)

- capsid: outer protein layer

Incubation Period

the period of time between the viral infection to when symptoms appear and the disease manifests

Chloroplast

convert solar energy into molecular energy

Mitochondria

convert molecular energy into work

Human Impacts on Biodiversity

- deforestation

- fragmentation

- agriculture farming

- overexploitation

- resource extraction

- pollution

deforestation

clearing land for agriculture, urbanization, and infrastructure development destroys natural habitats, leading to the displacement of extinction of many species

Fragmentation

when environment is broken down into smaller parts, leaving animals isolated

agriculture farming

Monoculture: practice of growing one crop species in a field at a time- monoculture, heavy pesticide use, land conversion can lead to loss of diverse habitats

resource extraction

- mining, logging, oil

- can lead to habitat destruction, water pollution and more environmental damage, affects local biodiversity

pollution

- toxins, pesticides, plastics