Unit 1: Diversity of Living Things pt.1 Flashcards
What is biodiversity?
Refers to the variety of life in an area. It allows for systems to adapt to change over time.
3 levels of Biodiversity?
Genetic, species and ecosystem
Example of Keystone species and what they are?
Honeybees- they pollinate, allowing for plants to reproduce. (they have a disproportionate amount of responsibility in a habitat)
What kills off the bees?
Pesticide, Varrao mites, IAPV virus
Genetic Diversity
is the sum of all different genes in a particular species
Species Diversity
refers to the variety of species in an area (ecosystems are healthier when they have a variety of species to survive environmental changes)
Ecosystem Diversity
refers to the range of habitats and organisms and the connections between them (EX. “walking” ecosystem refers to the fact that many organisms live in or on other organisms)
The names of organisms reveal:
- the evolutionary history of their species
- ecological relationshps with other species
- distinguishing characteristics of that species
Taxonomy
refers to the scientific naming, identifying and classifying species
Who was the first scientist to develop a formal system of classification?
Aristotle
How did Aristotle group the organisms?
based on their habitat
Present-day classification was made by who?
Carl Linnaeus (1750s)
What are the 8 taxons? (in order)
Domain -> Kingsom -> Phylum -> Class -> Order -> Family -> Genus -> Species
Phylogeny
The history of evolution of a species or group of organisms
Taxon
Categories used to classify organisms
What are the 3 domains of life?
Bacteria, Archaea, and Eukayra
Characteristics of Archaea and Bacteria?
unicellular, no nucleus or other membrane-bound organelles, prokaryotic
Differences between prokaryotic ve eukaryotic organisms?
Prokaryotic- absent membrane-bound organelles, unicellular, smaller, simple complexity, circular DNA, Ex. Bacteria, archaea
Eukaryotic- present membrane-bound organelles, mostly multicellular some unicellular larger, complex, linear DNA, Ex. Animals, plants, fungi and protists
Similarities between prokaryotes vs eukaryotes
DNA, Plasma membrane, cytoplasm, ribosomes
what are the 6 kingdoms?
- Monera
- Protista
- Fungi
- Plantae
- Animilia
- Eubacteria
Who developed the theory of evolution?
Charles Darwin
(why are there three groups of life instead of two?)
the 3 domains include bacteria, archaea and eukaryotes. There are 3 because they all have unique characteristics that define and differentiate them. Though bacteria and archaea are both prokaryotic, they have different attributes, archaea have a more complex structure allowing them to survive in extreme conditions possibly being one the first living organisms. They are very important to distinguish to know how to identify and classify organisms as well as their relationships and even evolution. Further showing the importance of why those distinctions need to be made.
Places Archaea can be found?
- hot springs
- acidic and basic waters
- seafloor vents (temp > 100 degrees)
- inside volcanoes
- hot coal and rocks deep below the earth’s surface
Difference between Archaea and Bacteria?
Archaea are more complex than bacteria, those organisms can survive extreme conditions (possibly making them the first living organisms), they have a unique cell membrane that no other organisms possess, and all archaea are anaerobic (obtain energy from inorganic molecules or from light)
Classes of Archaea
- Methanogens are methane-producing, live in oxygen-free environments and produce methane as a waste
- Halophiles- salt-loving
- Thermoacidophiles- heat and acid-loving
Shapes of Bacteria
Coccus (circular), Ex. Pneumonia
Bacillus (rod-shaped) Ex. E.Coli
Spirillum (spiral or curved) Ex. Lyme disease
Bacteria cell wall structure
- nearly all bacteria have cell walls outside their plasma membranes but they are very different from plants
2 types of cell wall (bacteria)
type 1- composed of peptidoglycan (thick coat of sugars)
type 2- a thin coat of peptidoglycan, plus an extra membrane
methods of bacteria movement:
- flagellum (whip-lie tail)
- twist like a corkscrew (spiral bacteria)
- some glide on film of slime
Main nutrition modes of bacteria:
Hetertroph- takes up organic molecules from the environment by eating other organisms
photoautotroph- uses sunlight to make carbon dioxide into carbon components like sugar
photoheterotroph- takes up organic molecules from the environment by eating other organisms and also uses light energy
chemoheterotroph- uses energy released through the chemical reactions (ex. ammonia, hydrogen sulphide, and similar chemicals
Bacteria Reproduction
Binary fission (cell splits into two and genetically identical, asexual)
Transduction
viruses that infect bacteria transmit genetic material from another source
Endospores
form when environmental conditions make normal functions too difficult. A small amount of cytoplasm and DNA form a tough capsule
Viruses are:
- Acellular
- Has no metabolism
- Considered non-living
- has DNA and RNA
- protein capsids
Lytic cycle
the virus unloads its genetic material, takes control of the cell, replicates necessary virus material (DNA and proteins) and causes the cell to burst and release new viruses. (known as cell death)
Lysogenic cycle
viral genes are incorporated into the host’s cell DNA, the host cell reproduces normally, an environmental change triggers the virus to separate from the host DNA, and the viral DNA in each host cell enters a lysogenic cycle.
Certain viruses do not kill outright:
cancer-causing and bacteria infecting
Viruses are NOT affected by antibiotics, but only a few such as:
- polio
- smallpox
- hepatitis B
- chicken pox
Protista are:
single cellular, some multicellular, some heterotroph and autotroph, are all eukaryotic
Example of protist
Algae (red algae, dinoflagellates) (blue and green are bacteria)
what condition does red algae cause?
“red tide” or HAB, produces a toxin
Example of multicellular protist
seaweed, kelp
process of prokaryotes -> eukaryotes
- infolding- inward folds of the plasma membrane, it formed endoplasmic reticulum, Golgi apparatus and nuclear envelopment
- endosymbiosis- smaller prokaryotes captured in larger hosts. Symbiosis occurred, evolving to organelles like mitochondria and chloroplasts
Movements of Protista
- pseudopodia (“false foot”), used by amoeba
- flagella (long hair life projections), used by zooflagullate
- cilia (smaller flagella, move in groups or cover organisms), used by ciliates
- passive movement (wind, water, passing animals)
- some protists inject spores
Mitosis is used by:
Amoebas, paramecium, and most ciliates (lack genetic diversity)
Animal-like protists:
- heterotrophic, single cellular, motile and aquatic
Plant-like protists:
- autotrophic, most aquatic, some can be very large seaweed
Fungi-like protists:
- heterotrophic, may be able to glide from one place to another
Kingdom Protista:
- unicellular, motile, aquatic, eukaryotes
Why aren’t viruses considered living?
they lack many properties associated with living organisms, such as not being made of cells, they don’t grow, and can’t make their own energy
loss of biodiversity:
threatens the viability of the ecosystem
the greatest threat to biodiversity
habitat loss
phylogenetic tree shows:
the evolutionary relationships between and among species
diplo=
doubles
strepto=
long chains
staphylo=
clusters
where is the DNA in bacteria found
nucleoid
what process is when bacteria pick up DNA from the surrounding area
Transformation
autosome chromosomes are
all chromosomes except sex chromosomes
