Unit 1 Flashcards
Diversity of Living Things
What is Biodiversity?
The variety of life on earth
- the essential interdependence of all living things
What are species?
A group of organisms that can interbreed in nature and produce fertile offspring
What are the 3 species concepts used to identify what a species is?
- the MORPHOLOGICAL species concept
- The BIOLOGICAL species concept
- The PHYLOGENETIC species concept
What is the morphological species concept?
Anything that focuses on body shape, size and other structural features
Advantages: easy to classify + most widely used
Disadvantages: deciding how much of a difference there can be in appearance (how much variation can there be)
What is the biological species concept?
The ability for organisms to interbreed in nature and produce a fertile offspring that can live
Advantages: widely used by scientists
Disadvantages: cannot be applied in all cases
- species can be separated and never get the chance to interbreed
- organisms that reproduce asexually
- species who are fossilized or extinct and are no longer producing
What is the phylogenetic species concept?
the evolutionary relationships among organisms (the history or DNA)
Advantages: can be applied to extinct species and focuses on using DNA analysis
- can be used to find new species
Disadvantages: evolutionary histories are not known for all species
what are keystone species?
A species on which other species in an ecosystem largely depend, and if they were removed, the ecosystem would drastically change.
What is taxonomy?
the branch of biology that names and groups organisms according to their characteristics and evolutionary history
- science of classifying organisms
has 2 purposes:
- to identify organisms
- to represent relationships among them
What is Binomial Nomenclature and how to use it?
Organizing an organisms scientific name into a combination of 2 terms
- Genus name and species
- both terms are italicized and the first letter of the genus is capitalized
what is the genus?
the taxonomic group of a closely related species
name is indicated by similarities in:
- anatomy
- embryology
- evolution
What is the Hierarchical Classification?
the method of classifying organisms in which species are arranged in categories from most general to most specific
What is a rank and taxon?
rank: each of the eight taxonomic categories is known as a rank
taxon: the name of each rank is called a taxon
the 8 taxonomic levels (8 taxa)
1.domain
2. kingdom
3. phylum
4. lass
5. order
6. family
7. genus
8. species
What are the 3 domains?
- Domain archaea
- includes newly discovered cell types
- 1 kingdom: the Archaebacteria - Domain Bacteria
- includes other members of old kingdom Monera
- 1 kingdom: the Eubacteria - Domain Eukarya
- includes all kingdoms composed of organisms made up of eukaryotic cells
- 4 kingdoms: – Protista, Fungi, Animalia, Plantae
What are the kingdoms of life?
organisms in each kingdom are similar in their cellular structure, methods of obtaining nutrients, and metabolism
- Archaebacteria
- Eubacteria
- Protista
- Fungi
- Plantae
- Animalia
What are prokaryotic and eukaryotic cells
Prokaryotic: a smaller, simple type of cell that does not have a membrane-bound nucleus
- Bacteria and archaea are prokaryotes
Eukaryotic: a larger, compex type of cell that does have a membrane bound nucleus
- Protista, plants, fungi, and animals are eukaryotes
Explain the factors of a virus
- Viruses are functionally dependent on the interval workings of cells
- can be found in both eukaryotic and prokaryotic cells
- not able to live independently outside of cells
- they must invade cells are use host cells machinery for survival and reproduction
- viruses are found everywhere
- consist of a core of nucleic acid (either DNA or RNA) and a protein coat (capsid)
- not considered “living organisms”
- they have one sign of life: the ability to reproduce at a fast rate inside a host cell.
viruses + bacteriophages?
bacteriophages: viruses that attack bacteria
both invade cellas and use the host cell’s machinery to synthesize more of their own macromolecules
the virus undergoes replication within a host cell
once inside the host they will either go into a lytic cycle or lysogenic cycle.
what is the lytic cycle?
the replication procces in viruses that occurs inside the host cell and makes new viruses
- destroys the host cell furing reproduction
- you get immediate disease symptoms
has 5 parts
1. attachment (protiens on surface of virus bind to protien on the surface of the host cells membrane)
2. Insertion (the virus injects its genetic material (RNA/DNA) into the host cell
3. Host DNA disrupted
4. replication of viral parts and assembly (the host makes more viral DNA or RNA protiens and new viral particles are assembled)
5. Lysis/release (the host cell breaks open and releases new viral particles)
Lysogenic Cycle?
the replication process in viruses where the viral dna enters the host cell without killing the host
incorporates viral DNA into the hosts chromosome
the virus may stay dormant until it activates and can produce more viruses.
- dna becomes part of the host cells chromosome
- cell division ( provirus replicates with hosts chromosones)
- provirus leaves the hosts chromosome.
What are the 4 shapes that classify a virus? give description
- Helical
- rod shaped
- coiled to helix shape
- may look like a hollow tube
- forms a capsid
- protein subunits stacked around nucleic acid - Icosahedral
- protien subunits form geometric rectangular patterns
- like a soccer ball - Enveloped virus
- capsid is enclosed in phospholipids (fatty acids) or proteins taken from host cell - complex virus
- includes many shapes in one
- common shape for bacteriophages
- has a head and tail
Retrovirus + provirus?
retrovirus: single-stranded RNA viruses that convert thier RNA to the hosts DNA so viral DNA can join with host DNA
- a virus that uses RNA as its genetic material
Provirus: after a DNA virus has been incorprorated into a host cells chromosome
5 transmissions of viruses
- Respiratory Transmission
- Fecal-Oral transmission
- blood-borne transmission
- sexual transmission
- animal or insect vectors
what do Bacteria and archaea have in common
- both are domains within prokaryotes
- living things without a nucleus
what makes archaes so unique
- they can survive in extreme : tempreatures, pH, darkness, gasses, habitats
(lipids help in hot temp and fatty substances help in cold temp) - do not use oxygen for energy (anaerobic) (live in oxygen free envionrments)
- instead gather it from inogranic molecules or light
- use carbon dioxide, nitrogen gas, hydrogen sulfide as energy
- vayr similar to bacteria biochemically but are genetically different
—- RNA chemical differences
—- chemical composition
—- cell membranes - are methogens (produce methane (waste)
what are the 3 major groups of archaea
- thermophiles (heat lovers)
- acidophiles (acid-loving)
- halophiles (salt-lover)
What is the kingdom eubacteria?
- organisms commonly refered to as “bacteria”
- need oxygen
- classified by shape, cell wall, and energy source
What are the 3 bacterial shapes?
- COCCUS/COCCI
- spherical shape
- caused by tooth decay
- resist drying - BACILLUS.BACILLI
- rod-shape
- caused by food poisonsing
- good at absorbing nutrients - SPIRILLUS/SPIRILLUM
- spiral shape
- caused by syphillus (sexually transmitted infection)
- moves through fluids with less resistance
Bacterial shape 3 prefixes
- DIPLO-
- arranged in pairs - STAPHYLO-
- arrange in clusters - STREPTO-
- arranged in chain
how and 2 indicators for cell wall structure?
using staining techniques to fin the difference’s in amino acids and sugar molecules in cell walls.
- gram-positive: think protein outer layer (purple)
- Gram negative: thin protein outer layer (pink)
4 major Energy sources?
- HETEROTROPHS
- eats organic molecules from envionrment
- eats other organisms - PHOTOAUTOTROPH
- uses sunlight to make energy - PHOTOGETROTROPH
- both 1 and 2 - CHEMOHETEROTROPHS
- uses energy released through chemical reactions
What is the asexual reproduction of bacteria?
Binary fission
- as a cell grows, it makes a copy of its chromosome
- once it reaches a certain size the cell separates and creates a partition (septum) between the 2 cells
- the cell splits into 2 small identical cells
- produced within 20 min
Name and explain the 3 sexual reproductions of bacteria
- conjugation
- producing cells with new genetic codes
- to better adapt to changing conditions
- a pilus connects the cells together and transfers the dna into the other - Transformation
- takes up pieces of DNA from environment (nearby bacteria) - Transduction
- bacteriophages infect bacteria
- cary bacterial genes from one cell and inject them into another
What are endospores?
During unfavourable conditions an edospore is a outer covering surrounding the DNA
- it is a seed like structure that can resist extreme heat, cold, drying or damaging chemicals
- during this stage the cell canot grow or reproduce.
- can be destroyed by a pressurized steam container called “autoclave”
What are protists?
a eukaryotic organism, usually contains on cell, that is not a fungus, plant, or animal
What are the 3 groups of protists:
- animal-like protist (protozoans)
- plant-like protist
- fungus-like protist
Explain Animal Like Protists:
- can also be called protozoans
- they are heterotrophs ]
- consume prokaryotes, other protozoans, or organic waste
- Some of the species are parasites that take nutrients from the organisms that they reside in
What are parasites
an organism that benefits by living in or on another organism at the expense of that organism
The Cerozoans (animal-like protists)
cell membrane can change shape - using internal cytosekeleton to move and create different forms (amoebas)
Has pseudopods (temporary cytoplasm extension that helps with motion and feeding)
amoebas: spread through drinking dirty water
The Ciiates(animal-like protists)
protists that have have many short hair like prjections that cover the surface of the cell
These are called cilia
- used for movement, feading by sweeping food particles under the cell
–> EX paramecium
Paramecium life cycle
paramecium join at the mouth pore and exchange DNA from micronucleus
- After they divide through mitosis, the offspring are different from original parents
- this is a form of sexual reproduction
Flagellates (animal-like protists)
have one or more flagella that whip from side to side to move them about
- they have a hard protective covering over membrane
Flagella: tail like structure for movement (whips around at end of cell)
The sporozoans(animal-like protists)
parasites og animals that take nutrients from host
- reproduce asexualy and sexually
- alternates between 2 hosts
- cauase malaria in humans (plasmodium)
Fungus-like Protists
heterotrophs that aborb nutrients from other living organisms, dead organisms, and waste
- reproduce spores like fungi
- the cell wall is different from fung
2 distinct types:
- slime mould
- water mould
Plant- Like Protists
- also called phytoplankton
- conatins chloroplasts that carry out photosynthesis
Diatoms: Plant- Like Protists
- free flowing aquatic organisms
- rigid cell walls that contain silica(a common ingredient in glass/sand)
- usually reproduce asexual but under unfavorable conditions they reproduce sexually
Dinoflagellates:Plant- Like Protists
have 2 flagellas at right angles to each other that spin in water and move through water.
- reproduce very easily (results in a population explosion called bloom, algal bloom)
- EX red tide: a coastal phenomenon in which dinoflagellates that contain red pigments are so concentrated that the seawater has a deep red colour
Euglenoids: Plant- Like Protists
- over a thousand species
- mostly found in shallow freshwater
- have both chloroplasts and flagella, which help conduct photosynthsis and absorb nutrients
- have both animal and plant like characteristics
- autotrophs in sunlight and heterotrophs in dark.
Kingdom Plantae
plants are eukaryotic
cell walls that contain cellulose
can be arranged into a few major groups (based on presence or absense of vascular tissue and seeds)
- Non vascular Plants : bryophytes
- earliest known terrestrial plants
- dont have vascular tissues
- depended on the procces of diffusion and osmosis to transport nutrients
- generally grow on the ground with tang;ed vegetation
- have no roots but instead have a root like structure called “rhizoids”, which do not grow deep into the ground
- uses water from rain to reproduce
- EX: MOSS, LIVERWORT, HORNWORTS
Seedless vascular plants
vascular tissue allwos them to grow tall and give structural support to gain sunlight
uses water vapor to reproduce
forms a vascular tissue with xylem and phloem to carry material throughout the plant - called vascularization
- EX, FERNS
Seed producing Vascular plants
have many benefits
allows sexual reproduction without the presence of water
protection against harsh environments
has 2 categories of seed-producing vascular plants
1. GYMNOSPERMS
2. ANGIOSPERMS
- GYMOSPERMS
- can see the seeds clearly (naked)
(include large trees, pines - the reproductive structures are called “cones” (contains male or female reproductive parts)
- the sperm of the male cone is transported to the - - female cone via pollen grain
(pollen grain is released into the wind for travel to female cones for firtilization
- ANGIOSPERMS
reproductive parts are in flowers and the seeds are in fruits
male gametophyte is reduced to a pollen grain
For small flowers, pollen grain is transported by wind
For large and colourful flowers, pollen is transported by animals
fruits are a mature ovary of a flower that protects and disperses formant seeds
Kingdom Fungi
fungus/fungi - heterotroph and eukaryotic organism whose cell walls contain chitin
- they are stationary
- all fungi are multicellular except YEAST
Structure of Fungi
made up of mostly eukaryotic cells (contain numerous organelles
- their cells do not contain contain chloroplasts and cannot carry out the process of photosynthesis
- they are surrounded by a cell wall that is made up of chitin
What is Chitin
- hard material found in the external skeleton of invertebrate (cold blooded animal with no backbone) animals like insects
3 Basic Fungi Anatomy
- Hypha (hyphae)
- a multicellular, thread like filament that makes up the basic structure of the fungi - Mycelium (mycelia)
- a complex net-like mass made of branching hyphae
- live in the soil and other nutrients
Fruiting Body:
- reproductive structure on fungi that produces spores
- the top half of the fungi
Saprophytes
- fungi that feed on dead organic matter
- important decomposers that break down large, complex organic molecules into smaller ones
- by doing it they release nitrogen and phsporous into the soil
predatory fungi
- soil fungi with mycelia that traps prey
- Arthrobotrys specifically feed on tiny worms called nematodes
Symbionts:
TYPE 1: MYCORRHIZAE
- myco = fungus, rhiza = root
- hyphae grow around plant roots and enter root cells and helps plants absorb nutrients
- plants produce sugars from photosynthesis absorbed by fungi
- this is a symbiotic relationship
TYPE 2: LICHENS
- form a unique organism that depends on a relationship between 2 species
- there are an important food source for animals
- some are used for natural dye for wool and colour used in litmus paper
Parasites
absorbs nutrients from living cells of hosts
- harms the host organism
- mostly lives inside the host organism
- EX: FOOD MOULD, ATHLETES FOOT
5 fungi groups
they are based on the structure of the fruiting body that they produce.
- Fungi imperfecti (phylum deuteromycota)
- not known to reproduce sexually
- reproduces asexually
- diverse phylum of fungi due to differences
EX: LEMON MOULD AND PENICILLIN, CYLOSPORINE - DRUGS USED TO SUPPRESS IMUNE SYSTEM, BLUE CHEESE
- Chytrids (Phylum Chytridomycota)
- mostly unicellular
- aquatic
- spores have flagella
- can be parasitic or saprobial
EX: POTATO WART FUNGUS MAKES DEFORMED POTATOES
- Zygospore Fungi (Phylum Zygomycota)
- multicellular and terrestrial
- can sexually and asexually reproduce
- after 2 haploid hyphae fuse nuclei together, they develop zygospores
- a thick wall is produced around the zygospore to protect it from drying and unfavourable conditions
- EX: FOOD MOULD
Sac Fungi ( phylum Ascomytoca)
- produces small sacs during sexual reproduction
EX: YEAST, TRUFFLES & MILDEW
Club fungi ( Phylum Basidiomycota)
- fruiting bodies release spores called basidospores from basidia (a club shaped hypha found in members of basidiomycotes)
- network of hyphae spreads underground
- EX MUSHROOMS, PUFFBALLS
vertabrate vs invertabrate
vertebrate: an animal with an interval skeleton and a backbone
Invertebrate: an animal that does not have a backbone
how can you classify the complexity and advancement of an animal
- body organization: animals tissues, organs, organs system
- Digestive tract or gut
- does the animals gut have one opening ot two - body symmetry
- radial symmetry, bilaterial symmetry or asymmetry - Arrangement of cells into germ layers
- how many germ layers does the animal have - body cavity (coelom) formation
- what kind of coelom is located between the body wall and gut
What is cephalization?
concentration of sense organs and nerve cells at the front end (anterior) of the body
3 germ layers of an animal
- ectoderm: the outer layer
- gives rise to skin and nervous system
- hairs, nails, feathers, scales (complex animals) - mesoderm: middle layer
- gives rise to muscular skeleal, circulatory, excretory and reproductive system
- found in bilaterally symmetrical organisms (except flatworms) - Endoderm: inner layer
- gives rise to digestive tract and respiratory systems
what is a coelom?
a fluid filled body cavity that provides space for the development and suspension of organs and organ systems
What do all chordates have (vertabrate animals)?
- most complex and advanced animals
- DORSAL NERVE CORD: A tube-shaped cord that extends along the nack of the body (nerve branches)
- NOTOCHORD: rod of cartalage found akong dorsal lenghth of body
- PHARYNX: passageway that is part of both digestive and respitory tract
Embryonic Development:
Organisms in Kingdom Animalia can be divided into two categories based on the first opening of the embryo, called the blastropore:
- Protostomes:
mouth opens first
– mollusks, worms, arthropods
- Deuterostomes:
– anus opens first
- echinoderms, chordates
Climate changes 6 potential effects:
- disease outbreaks
- plant migrations
- animal migration
4, extreme weather - increased co2 levels
- water availability and quality
Habitat loss (deforestation)
- caused by demand for wood products
- HABITAT FRAGMENTATION: smaller patches of developments isolated from each other
- animals and plants are forced into confined areas
OVEREXPLOITATION
- when humans harvest many natural resources faster than the resources can reproduce and replenish
- over hunting/overfishing
Invasive species
- causes problems if no natural enemies are present
- can put ecosystems at risk
Dead zones
- areas in bodies of water with low levels of oxygen
- cannot support life
- due to polution, sewage, fertilizer run of
Synergistic Effects
- the combination of several human activities acting on the enviornment
ex-situ stratagy to conserving biodiversity
- happens when species habitat is threatened or cease to exist, or is population is too small
- species get reintroduced into the wild
In-situ strategy to conserving biodiversity
establishing protected areas, restoring habitats, and enacting protection laws
- restoration programs to bring back extirpated species (species no long exist in one area but exist elsewhere)
