Unit 2 - biodiversity Flashcards
What are the three levels of biodiversity?
Genetic, species, ecosystem
What is genetic diversity?
the sum of all the different traits/characteristics found in a species (sum of all the different genes found in a species)
- high genetic diversity (sexual reproduction) allows for better chances of survival due to higher adaptability rates
- lower genetic diversity (asexual reproduction) more susceptible to diseases pray etc
The sum of all the different genes in a species?
Genetic diversity
What is species diversity?
Variety of species found in an area
- ecosystems = connections between species, therefore higher species diversity = healthier ecosystem (also helps survive environmental changes)
Variety of species found in an area
species diversity
What is ecosystem diversity?
Total number of habitats and organisms in an ecosystem, including all the connections between them.
- ecosystems can be large or small, eg. humans are a ‘walking ecosystem’
total number of habitats and organisms in an ecosystem, including all the connections between them.
ecosystem diveristy
Masss extinction?
Occurs when over 70% of living things die (we are currently in the midst of one)
definition of classification?
grouping similar things for a specific reason
Why do we need to classify?
- understand evolution and relationships between species
- Properly name-new organisms (and determine whether they are actually new)
- distinguish between harmful and non harmful organims
History of classification?
- Untill the 1800’s eveything was classified as either a plant or an animal
- plant (consitantly grew, didnt eat other organisms, did not move)
- animal (grew untill a certain point, moved, ate other things) - Around the 1990’s it expanded into 5 kingdoms
- protists
- fungi
- animals
- plants
- monera (microscopic organisms)
Current classifications/kingdoms
- plants
- animals
- protists
- fungi
- archaebacteria
- bacteria
*1234 are eukaryotes, 56 are prokaryotes
How do we classify organisms?
- Number of cells
- multicellular/ uni-cellular - Nutrition
- autotroph/heterotroph - Habitat
- where does it live? - Type of cell
- eukaryotic/prokaryotic - reproduction
- sexual/asexual
What are the domains?
- Archeabacetria (only contains archeabateria)
- Eubacteria (only contains bacteria)
- Eukarya (plants, animals, protists, fungi)
What is a species?
Organisms that are able to freely breed under natural conditions and produce fertile offspring (similar structure)
Morphology
species that produce asexually
Hybridization
The exception to the species rule. Two different species crossbreed
Who is the father of taxonomy ratings/the inventor of the binomial nomenclature?
Carl Linnaeus
Taxonomy ratings
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species
- it becomes more specific down the list
Binomial nomenclature?
Genus, species
eg. Canus, lupus
Genus is capitalized. Species are lowercased. If typing, italicized, if writing, underline
Dichotomous key
- a list of yes or no questions that scientists can use to classify different relatedness
- used to classify and identify species
- looks like a family tree when graphed
What is the history of a species based on?
- molecular genetics
- the iBOL uses a barcode system to scan a species DNA - Development similarities
- similar embryonic stages suggest that organisms evolved from one thing
- ie. All vertebrae have gills during the early embryonic stages, suggesting that they all came from one common ancestor - Structural similarities
- similar structures but different functions (eg. bone structure in legs)
Homologous structural similarities?
Same anatomical structure, different functions
Analogous structural similarities?
Same anatomical structure, same functions (ie. like wings in bats vs birds)
phylogenetic tree/cladogram and structure
- diagram that displays evolutionary links between organisms
- tips represent different species (if a tip doesn’t make it to the top that means its extinct)
- nodes represent common features such as vertebrae, fur development, etc. At each node there is a common ancestor implied as well)
phylogeny?
evolutionary relationships between species
What are clades?
Clades are groupings on a cladogram that share a common ancestor/node (they make a triangle)
- this generally means they are more genetically similar
definition of taxonomy?
The science of classifying things
Archea and bacteria similarities?
- both prokaryotes (no membrane-bound organelles, no membrane-bound nucleus)
- very small, only have a cell membrane and nucleus (DNA and ribosomes are free-floating)
- they both have one kingdom and domain
Archea and bacteria differences?
- different genetic lineages (separate domains and kingdoms)
- archea are considered ancient and live in extreme climates (live off ammonia)
- certain bacteria can make us sick, archea cannot infect us
- different cell walls and DNA
Archea bacteria
- prokaryotes
- single celled
- replicate by binary fission
- heterotrophic or autotrophic
- ancient
- live in very extreme climates such as volcanoes vents and hot acids
- EXAMPLES:
anaerobic methanogens (oxygen free, produce methane)
haliophiles (live in salt lakes)
Thermophiles (live in really hot conditions)
Bacteria
- prokaryotes (largest number on earth)
- single-celled
- replicate by binary fission
- heterotrophic/autotrophic
- they go through conjugation in which they share DNA to make other cells smarter
- important for the carbon/oxygen cycle (nirtogen fixation and decomposition)
EXAMPLE: Ecoli
Protists
- eukaryotic
- autotrophs or heterotrophs
- multicellular or single-celled
- reproduce sexually or asexually through binary fission
- kind of like the ‘catch all’, they just don’t fit into any other category
(plant like, animal like, fungi like)
-require a wet/moist environment - no cell wall
EXAMPLE: algae, protozoa
Fungi
- eukaryotic
- heterotrophs
- multicellular
- sexual and asexual
- cell wall isn’t made out of cellulose (made out of chitin, they dont have any chloroplasts)
- terrestrial
EXAMPLE: mushrooms, mold
Plants
- eukaryotic
- autotrophs
- multicellular
- sexual and asexual reproduction
- cell wall made out of cellulose (has chloroplasts)
- terrestrial and aquatic
EXAMPLE: flowers, ferns, trees
Animals
- eukaryotic
- heterotophs
- multicelular
- sexual and asexual reproduction
- terrestrial and aquatic
EXAMPLE: Fish, human
describe/ draw a prokaryotic cell
- chromosomes are unwound (thread-like), gathered in the center of the prokaryotic
- free-floating ribosomes (that look like dots)
- no membrane-bound organelles
- circular rings of DNA called plasmids
- contains pilus (string hairs)
Bactera structure
- very small (1-10 um)
- no membrane bound organelles
- contains cell wall and membrane
- free floating unwound chromomsome in the nucleic region
- free floating ribosomes
- plasmids
- could have a flagella
Bacteria shapes
- coccus (round)
- monococci (singular, round)
- diplococci (two, round)
- streptococci (string, round)
- staphylococci (bunch of them)
- bacillus (rod)
- monobacilli (singular rod)
- diplobacilli (two, rod)
- streptobacilli (string, rod)
-spirillum (spiral shape)
What are gram stains? how are they used? give examples
Gram stains are made from crystal violet and iodine. They are used to categorize bacteria into two groups:
- Gram positive
- turn purple
- have a thinner cell wall/membrane
- less pathogenic (more susceptible to antibiotics) - Gram negative
- remain their original colour
- cell wall/membrane is thicker
- more pathogenic (resistant to antibiotics)
Nutrition
why is it needed/what is it
name the different categories of bacteria nutrition
- Bacteria cells obtain nutrition from a source of carbon dioxide and an energy source
- photo autotroph
- sun (energy) co2 (carbon) - Chemoautotroph
- inorganic chemicals (energy) co2 (carbon) - Photoheterotroph
- sun (energy) organic compounds (carbon) - Chemo heterotroph
- organic compounds (energy) organic compounds (carbon)
Name all the different forms of bacteria respiration
- Aerobes (require air)
- obligate aerobes (absolutely need air) - Anaerobes (do not require air)
- obligate anaerobes (die with air) - Facultative aerobes/anaerobes (don’t care)
Binary fission (bacteria). Mutations?
- occurs in bacteria, archaebacteria, some protists
- asexual method of reproduction
- quicker than mitosis (skips a lot of steps, can be done in 20 min)
- Parent cell copies DNA
- Parent cell continues to grow and cells divide
- Two exact daughter cells are created
Mutations are rare, but because there are so many bacteria they tend to occur quite often. They are what cause genetic diversity in bacteria.
Conjugation
- occurs in bacteria, archaebacteria, some protists
- makes cells smarter
- in tough conditions, some cells are able to survive better than others due to the DNA on their plasmids (it can code for a stronger cell wall etc)
- cells can share their plasmids and help other cells survive
- A cell that doesn’t have a plasmid finds a cell that does (chemical reactions)
- The two cells connect via their pilus (protein bridge)
- Plasmid copies itself, unravels, and goes through the hollow protein tube created by the pili
- The two cells unattached, one cell now has a different genetic makeup
Endospores
When a gram-positive bacteria undergoes very bad conditions, it can create an extremely thick cell wall around itself and stay dormant until conditions get better (made from spores)
When a gram-positive bacteria undergoes very bad conditions, it can create an extremely thick cell wall around itself and stay dormant until conditions get better (made from spores)
Endospores
Types of bacteria
Proteobacteria Green bacteria Cyanobacteria Gram positive - disease causing Spirochetes Chlammydias
Endotoxins, Exotoxins
Endotoxins: gram negative bacteria split, release harmful toxins (fever, vomiting, not fatal)
Exotoxins: Bacteria multiply, release toxins (toxic, fatal)e
What is a virus?
A virus is DNA or RNA, enclosed in a protein shell called a CAPSID
- it is non living (only ‘lives’ when its in another cell, isnt a cell itself)
- dont have any organelles, dont use ATP
- specific viruses invade specific cells
-
how do you classify a virus?
- Morphology (shape)
- What kind of cell does it invade
- method of ‘reproduction’ (lytic or lysogenic )
- What disease does it cause
- DNA or RNA
Main virus types and shapes
- Helical (spiral)
- tobacco mosaic virus - polyhedral (many flat sides)
- adenovirus - Spherical (round, tags)
- influenza - Complex
- bacteriophage
Describe/draw bacteriophage. How does it work?
- DNA is in a protein capsid
- collar
- Sheath
- Baseplates
- Spikes
- Tail fiber
Bacteriophage lands on a cell. Its spikes and tail fibers attach to the cell, as its sheath spirals into the cell and releases the DNA into it.
What are the two methods of virus ‘reproduction’?
- Lytic cycle
2. Lysogenic
Lytic cycle
- shorter virus reproduction
- always resists in lysis (the cell breaking open)
- Virus attaches itself to the cell wall (protein tail fits well)
- Virus tail releases an enzyme that dissolves the cell wall
- Virus injects DNA into the cell
- Viral DNA takes over the hosts activity and destroys its DNA
- instructs the cell to create copies of the virus DNA and new capsid (making new viruses)
- Viruses produce an enzyme that breaks down the cell wall, releasing the new viruses (lysis)
- cell dies, viruses attack new cells
Lysogenic cycle
- longer way of viral reproduction, stays dormant until lysis is triggered
- Virus gets in the cell (same as lytic)
- Virus inserts its DNA into the cells DNA, so that when the cell reproduces, so does the viral DNA (lysogeny, the virus is still dormant
- Due to some sort of environmental stimulus, the viral DNA is activated, and the virus goes into the lytic cycle)
Examples: Shingles, HIV, AIDS
RNA viruses
- virus contains RNA instead of DNA
- can make the cell produce viral proteins
- because they dont contain acc DNA, they can only reproduce via the lytic cycle (they cant merge DNA with a host)
Retrovirus
- creates DNA from RNA using reverse transcripts
eg. HIV
How do viruses spread?
- animals (vectors such as mosquitoes molaria, mammals rabies etc)
- water
- global spread due to travel
Animal like protists
heterotrophs,4 groups
- zooflagellates (flagella)
- single celled, heterotrophic, eukaryotic
eg. sleeping sickness - amoebas
- single celled
- create pseudopods to move and eat
- feed through endocytosis
eg. Entamoeba - ciliates
- covered in cilia (hairs)
- have a pellicle that maintains their shape
- aquatic heterotrophs
- these are the ones that have almost a fully functioning digestive system. They have an oral grove and an anal pore, food vacuoles
eg. paramecium
- sporozoans
- produce spores during asexual reproduction
- non motile, parasitic
eg. plasmodium, malaria
The plasmodium
animal like protist (sporozoan)
- mosquito bites human and gets plasmodium sex cell
- sex cells join in the mosquito and make new plasmodiums
- sexual, new forms reproduce asexually
- mosquito bites a human, releasing asexual plasmodiums into the blood
- Asexual form infects the liver
- continues to asexually replicate, breaking down cells
fungus like protists
heterotrophic, decomposers
- Acellular slime moulds
- cellular slime moulds
- water moulds
Plant like protists
contain chlorophyll (carry out photosynthesis)
1. algae (single, multicellular)
move in spinnnig motions, have 1 or two flagella, are lumnicent
- green algae (single or colonial)
freshwater, one flagella, first plants
endosymbiosis
cell that lives within another cell
euglenoids
plant like protist (algae).
unicellular flagellates.
Autotrophic when light is available, heterotrophic when it isn’t.
diatoms (algae)
plant like protist
single celled, key food source in ecosystems
dinoflagellates (algae)
plant like protist single celled 2 flagella spin as a way of moving bioluminecent (glow) rapid growth/blooms
green algae
plant like protist fresh water single or colony of cells 2 flagella - possibly the first plants
Examples of helpful fungi, bad fungi
- used in bread, cakes etc
- wine, beer, alchohal
- pennicilin, antibiotics
- cheese
- soy sauce
- food spoilage
- shower mould
- ringworms
- athletes foot
Fungi General characteristics
- eukaryotic
- heterotrophic
- uni cellular or multicellular
- sexual/asexual reproduction
- cell walls are made out of chitin, which is more durable
- they are SAPROBES (they absorb nutrients from decaying matter)
- DIKARYOTIC (TWO NUCLEI)
- can be parasitic
saprobes
absorbes nutrients from decaying matter (ie. fungi, for example a mushroom)e
How do fungi eat/absorb nutrients
- Endocytosis (envelop food, then digest it)
- Hyphae (the thread like structures that build fungi, they secret enzymes that break down the food, making it easier for fungi to absorb the nutrients)
mycelium
Part of a mushroom that grows underground. Made from hyphae filaments,hyphae are seperated bby SEPTUM
Fungi reproduction
- asexual or sexual reproduction, through spores (all of the spores are haploid)
- spores produced in the sporgangia (under the mushroom cap) burst
- haploid spores are released
- spores grow hyphae
- spores and hyphae attached to other spore hyphae, eventually a new sporgangia is made (fruiting body)
What are the different categories of fungi (based on sexual reproduction)
- Case like (Zygomycota)
- Sac like (Ascomycota)
- Club like (Basidiomycota)
Case like fungi
zygomycota
example. Rhizopus (bread mould)
- terrestrial saprobes (land, eat decomposing matter)
- sporangia produces spores
- spores are in a caselike structure (mushroom cap?) called a sporangium
- hyphae extend down into the food source to get nutrients (rhizoids)
Sac like fungi
Ascomycota
example. mildew, yeast, truffles
- spores are in sac like structures called ASCUS (look like cups)
- ASEXUAL: create spores called conidia (good conditions)
- SEXUAL: create spores called ascospores (dormant, bad conditions)
Yeast
- unicellular, sac like fungi
- reproduce asexually by budding (under ideal conditions)
- reproduce sexually through ascospores (bad conditions, need genetic diversity to survive)
carry out anaerobic respiration (ideal for baking)
Club like fungi
Basidiomycota
- store bought mushrooms
- saprobes or parasites
Plant life cycles
plants alternate between generations
1) one generation is haploid (gametophyte)
2) one generation is diploid (sporophyte)
- plants produce haploid spores that divide into a haploid generation
- haploid plants produce gametes, which fuse into diploid zygotes, creating a diploid generation
in primitive plants gametophyte generations dominate (haploid)
in seed producing plants sporophyte generations dominate (diploid)
what are the four main groups of land plants?
Bryophytes (moss, non vascular)
pteridophytes (ferns, vascular)
gymnosperms (pines, conifers, vascular)
amniosperms (flowering ,vascular)
Vascular systems in plants
- evolved to allow plants better access to the sun (theyre able to reach higher, get more light)
- XYLEM - carry water and minerals from the roots (only flows up)
- PHLOEM - distribute carbohydrates throughout the plant, found everywhere and flows in every direction
surrounded by the endodermis
Bryophytes (characterisitcs and examples)
- land plant, no vascular system/bundles
- evolved first
- no TRUE stem, leaves or roots
- no specialized tissues that transport material (very small chloroplasts)
- live in moist environments
EXAMPLE: moss, liverworts, hornworts
Pteridophytes (characteristics and examples)
- land plant, first to evolve with vascular system/bundles
- produce SPORES as means of reproduction
EXAMPLE: club mosses, horsetails, ferns
Who are seed producing, vascular plants?
Gymnosperms, angiosperms
Gymnosperms
- land plants, seed producing, vascular
CONE PRODUCING
- male and female cones (male = pollen cones, female = seed cones)
wood is SOFT
EXAMPLE. Pine tree, conifers
Angiosperms
- land plant, vascular, seed producing, flower producing
- reproduce sexually through pollination
- seed develops into fruit
Angiosperm structure
- outer areas made of sepal and petals (smell and flowers serve no other purpose than to attract pollinators)
- Has both male AND female parts
- STAMEN = male reproductive part
- ANTHER = produces pollen
- CARPEL = female reproductive part, eggs found in its base
- STIGMA = carpel opening
- STYLE = sperm travels down style, fertilizing egg
different types of pollination
self pollination - pollen from same plant fertilizes same egg
cross pollination - pollen from another plant fertilizes an egg (from the same species
- can be carried by air wind and water
monocot vs dicot
COTYLEDON
monocot - 1
dicot - 2
FLOWER PETALS
monocot - multiples of 3
dicot - multiples of 4 or 5
ROOTS
monocot - fibrous
dicot - tap
VASCULAR BUNDLES IN STEMS
monocot - random
dicot - in a circle
LEAVES
monocot - thin, parallel veins
dicot- broad, net veins
EXAMPLES
monocots - grass, bananas grains
dicots- oaks, maples, dandelions, daisy
*****THERE ARE LESS MONOCOTS THAN DICOTS
what are monocots and dicots used to classify
angiosperms
cotyledon
a patch inside the seed ( a ‘seed leaf’, the first leaf that grows out of a cells embryo)
monocots - 1 cotyledon (don’t nourish the embryo)
dicots - 2 cotyledons (nourish the embryo)
importance of roots
- They anchor plants to the ground
- they pull nutrients and water from the soil
- transport water and nutrients to the rest of the plant
- store carbohydrates
Adventitious roots
roots that grow from non-root tissues
eg. If a corn falls, it will start growing roots
Root tissues
- Epidermis
- Cortex
- Endodermis
- Vascular bundles
Epidermis
- outer layer of a root
- one cell thick
- has root hairs (increases SA of absorption)
- absorbs water
- protects inner cells
Cortex
- layer underneath epidermis (thick)
- stores carbohydrates
- transfers water from epidermis to vascular bundles
Endodermis
-layer underneath cortex
-waxy, resistant against water
- surrounds vascular tissues
CASPARIAN = prevents leakage of water or nutrients into the outer layer of the roots
osmosis
- happens due to the concentration gradient
- water moves from an area of low solute concentration, to high concentration
- moves with the concentration gradient and therefore does not require any energy
PASSIVE ACTION (NO ENERGY)
how does water move into the roots? minerals?
water - osmosis
minerals = active transport
Active transport
- cell needs to move substances across a membrane against the concentration gradient
- requires ATP/ energy (goes from an area of high concentration to low concentration)
- passes through the PROTON PUMP, which is a protein
EXAMPLE. Minerals going into the root,
Phytomediation, example
phyto- clean up
mediation - fix
the process in which plants clean up environments (they absorve toxic substances through their roots such as lead, arsenic, and uranium)
EXAMPLE: cattails and sunflowers
importance of stems
- allows stems to get closer to the sun
- supports leaves (needed for photosynthesis)
- transports nutrients throughout the plant)
Types of stems, examples
- Herbaceous
-monocot and dicot (monocot has scattered vascules, dicots are arranged in a circle - phloem in the middle)
-flexible, less strong
-does not expand
-VASCULAR CAMBIUM = separates xylem and phloem
EXAMPLE: flowers - Woody
- dicot only (vascular bundles on the outside)
- hard, rigid
- VASCULAR CAMBIUM = grows new xylem and phloem every year
- young xylem (sapwood) carries water and minerals
- old xylem hardens into heartwood
Special stems
Tubers: stems that grow underground and store food (potato)
Bulbs: underground, short stem surrounded by modified leaves
(onions)
Rhizomes :underground, connect to other stems like a network of roots
(grass)
Leaves on angiosperms
monocots- thin, long, parallel veins (vascular bundles are small, closer together)
dicots- broad, network of veins (vascular bundles arn’t the same size or equally distanced)
what controls the when carbon dioxide can enter the plant?
Guard cells expand to close the stomata, which are openings in the plants stem.
leaf structure
- cuticle = protective waxy substance
- upper epidermis = protective barrier for the inner tissue
MESOPHYLL = tissue containing chloroplasts - palisade layer = densely packed mesophyll
- spongy mesophyll = loosely packed mesophyll
5.Stomata = openings in the stem that allow for movements of gases (underneath the leaf) - Guard cells = control the opening and closing of stomata cells by swelling
simple diffusion
- movement of particles from an area of high concentration to an area of low concentration
- no energy requires (passive action)
xylem structure
- the xylem has a really strong cell wall
- it is a continuous tube of cells (dead)
- walls consist of cellulose, lignin (which makes it strong)
- Contains parenchyma and sclerenchyma (also makes it stronger)
- transports water and minerals (only one way)
root pressure
- water enters the root through osmosis, minerals enter through active transport
- water pressure in the roots increases, pushing up sap (aka nutrients and water) up the xylem
- endodermis in the roots prevents backflow
- root pressure can only push water up a few meters
cohesion adhesion
- draws water up the xylem
- due to polarity, water molecules are attracter to the xylem walls (adhesion)
- water molecules are attracted to each other (cohesion)
- water is pulled up the xylem as the it leaves leaves through transpiration
Transpiration pull
- water leaves the plant through the stomata, forcing up water through cohesion
- water movement depends on transpiration rate
phloem structure
- alive
- has sieve plates in between cells
- lacks nucleus, but is attached to a neighboring cell that doES have a nucleous
- the neihbouring cell does all the work for it (sugar in and out)
- sugar travels up or down the tubes
pressure flow theory
- sugar moves from source to sink (from leaves to roots or from roots to leaves)
-sucrose enters/leaves phloem by active transport, water enters through osmosis
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