Orokaryotes bacteria are the planet's most ____________.
abundant innhabitants
What are the oldest organisms?
Prokaryotes
What are the two metabolically different groups of bacteria that evolved?
archaebacteria
eubacteria
What are most archaebacteria today?
methanogens
What do methanogens do?
use hydrogen to reduce carbon dioxide to methane
Whate type of anaerobes are methanogens?
obligate anaerobes
What are obligate anaerobes poisoned by?
oxygen
Where are methanogens found?
Swamps
Marshes
Digestive tracts of cows and other herbivores
What are archaebacteria called?
extreme halophiles
Where do archaebacteria live?
In very salty places such as the Dead Sea and the Great Salt Lake
Where do thermoacidophiles grow?
In hot, acidic environments such as the sulfur springs
What do many eukaryotic cells contain?
Other organelles thought to be descended from bacteria
Based on the theory of ________________, what?
endosymbiosis, chloroplasts in the cells of plants and algae are descendants of photosynthetic prokaryotes that were incorporated into a larger host cell
What are thought to be the result of endosymbiosis?
Mitochondria
What are mitochondria thoght to be the result of?
endosymbiosis
What is the simplest and most primitive method of reproduction?
Asexual reproduction
How and in what environment is asexual reproduction advantateous?
In a stable environment, enabling organisms to produce many well adapted offspring in a short period of time
What does an organism that reproduces asexually not need to do?
Expend energy producing gametes or finding a mate
What happens in budding?
A small part of the parent's body grows into a new individual
What is fragmentation and what organisms can do it?
The breaking of the body into several small pieces (sponge or echinoderms)
What is an advantage of sexual reproduction?
Provides a means of shuffling genetic material, quickly generating different combinations of genes among the individuals
What has been a principal factor in the evolutionary success of eukaryotes?
The rapid generation of genetic diversity produced by sexual reproduction
What is the raw material for evolution?
genetic diversity
What are the three types of life cycles that eukaryotes are characterized by?
zygotic meiosis
gametic meiosis
sporic meiosis
What is zygotic meiosis?
the simplest of sexual life cycles, the zygote is the only diploid cell and it undergoes meiosis immediately after it is formed so haploid cells occupy the major portion of the life cylce
Where is zygotic meiosis found?
In many algae
What is gametic meiosis?
The gametes are the only haploid cells; all of the other cells are diploid and meiosis produces gametes
Where is gametic meiosis found?
In most animals (humans)
What is sporic meiosis?
Plants have a life cycle that regularly alternates between a haploid phase a diploid phase
diploid phase: sporophyte produces spores
haploid phase: gametophyte produces gametes
What is a multicellular organism composed of?
Many cells that are permanently asociated with one another and that integrate their activities
What is the main advantage of multicellularity?
It allows for specilization
What do distinct types of cells form?
Tissues
What are tissues?
Groups of cells with a common structure and function
What are different tissues organized into?
Different organs
What are organs?
Structures with specific functions
When has multicellularity evolved many times?
In times among the protists
What are the three groups of photosynthetic protists that have species with multicellularity?
red algae
brown algae
green algae
What is taxonomy?
The science of classifying and naming organisms
How established binomial nomenclature?
Linnaeus
What did Linnaeus establish?
Binomial Nomenclature
What is a scientific name?
A unique two-word name
What is teh scientific name composed of?
The first word (genus) and the second word (species)
What did Linnaeus base the system of classification on?
An organism's form and structure organized into a hierarchical system of groups that increase in inclusiveness
What is a species?
A group of individuals that can breed with one another and produce fertile offspring
How are hybrids produced?
When individuals of different species interbreed
What are the six kingdoms all living things are classified into?
Archaebacteria
Eubacteria
Protista
Fungi
Plantae
Animalia
About how many species have beeen named?
1.5-2.2 milion
How many kinds of organisms do scientists predict there are?
At least 10 million
What happens in convergent evolution?
Organisms evolve similar feature independently , often because they live in similar habitats
What is a result of convergent evolution?
wings
What are similar features that evolved through convergent evolution called?
Analogous characters
What are analogous characters?
similar features that evovled through convergent evolution