Topic 1 - Introduction to Biology

Introduction to Science
The word "scientist" was only created in the late 1800's.  Isn't that crazy?  Only a bit more than a hundred years ago.  It is used to refer to people who study natural phenomena, nature and human artifacts in a systematic way.  Of course, there were people who were interested in such things before the word was created, but often they were quite careless in the way that they collected information and didn't go about observing and questioning in a "scientific" way.  Nowadays, this systematic way is called the SCIENTIFIC METHOD.

The Scientific Method
1. Identify and define the problem or question
2. Collect information
3. Propose a hypothesis (Definition: A possible explanation for phenomena, facts or a scientific problem that can be tested and answered.)
4. Design experiments to test the hypothesis
5. Carry out experiments
6. Analyze data
7. Draw conclusions
- if the conclusions support the hypothesis, repeat steps 5, 6 and 7 several times
- if the conclusions refute (don't support) the hypothesis, check the experimental design and revise it.

When a hypothesis is well-supported it becomes a theory.

In biology, we often try to describe very complex systems that include interactions between many animals, plants and the non-living environment as well.  To do this, we create models, which are schematic descriptions of the system, theory or phenomenon that account for the known or inferred properties and may be used for further studies of its characteristics.

In order for scientists to carry out experiments, they often work in labs or in the field with special equipment.  In grade 10, we will hopefully do some lab and field work (although not much, there will be more in grade 11 and 12!).

To find out more about the scientific method, lab equipment and safety and how to think like a scientist please click here

BIOLOGY
- study of life
What is alive?  How do we know?

1.  Metabolism (anyagcsere)
- uptake, transport or elimination of matter and energy
-nutrition
-respiration
-excretion
-circulation
       
2.  Growth and development
3.  Reproduction
4.  Movement
5.  Response to stimuli
     eg.  adaptations, homeostasis 

Biologists organize the world into non-living and living parts, with different levels of complexity, like this:
Organization
atoms                        ABIOTIC
molecules
cell organelles          BIOTIC
cell
tissue
organ
organ systems
organism
population                 MADE UP OF MANY ORGANISMS
community
ecosystem                  BIOTIC AND ABIOTIC
biome                         GEOGRAPHICAL ZONE
biosphere                   EARTH

Evolution: The continuous process of change in the living world (often associated with changes in the chemical and physical world)
Really briefly:
Billions of years ago, the Earth was very different from the way it is now.  It was essentially a giant ocean filled with abiotic (non-living) atoms and molecules.  It is often referred to as the "primordial soup".  As crazy as it seems, life developed from these abiotic molecules (more on that in grade 12).  Mind you, it was very, very, very, very, very, simple.  Over time these very simple life forms changed and increased in complexity to give us what we find on the Earth today.

Prokaryotes (aka bacteria) - they have no nucleus and that is what the word prokaryote means
Single-celled Eukaryotes (aka protists) - they have a nucleus (eukaryote means true nucleus)
Multi-celled Eurkaryotes - these are the fungi, plants and animals

Evolution is still occurring and life forms are changing as you read this.... Weird, isn't it?
In 1859, Charles Darwin published the "Origin of Species", which laid down the groundwork for evolution as we understand it today by considering relationships between species based on their ancestry.

Taxonomy: the study of grouping or classifying living organisms.


Humans have been trying to classify life for a long time
-Carolus Linnaeus created the 1st "natural" classification system in the 1735.  It was called natural because it was based on relationships between the organisms as assessed by their physical characteristics.  It grouped living organisms as species, then closely similar species and so on.  You can probably see where it might run into problems, with for example whales and sharks).  The Linnaean system gave each species 2 Latin names (binomial nomenclature) eg. Homo sapiens, which we still use today.

Famous Hungarian taxonomist: Kitaibel Pál (1754-1817): he discovered over 150 plants species and numerous animals too.


NOW, we use phylogenetic classification which is based on the evolutionary history of a species.  It uses:
ontogeny (development)
- genetics
- behaviour
to determine relationships

TAXA:

Kingdom          Animalia
Phylum            Chordata
Class               Mammalia
Order              Carnivora
Family             Felidae
Genus              Felis
Species            lynx

*an easy way to remember the order of the taxa is to use a mnemonic device:
King Philip Came Over From Germany Saturday

The scientific name of the species is its genus name and its species name: Felis lynx
This is called binomial nomenclature because it is a 2-name naming system.

There are 5 Kingdoms:
K. Monera - prokaryotes (don't have a nucleus), unicellular, aka bacteria
K. Protista - eukaryotes (have a nucleus), mostly unicellular
K. Fungi - eukaryotes, multicellular, aka mushrooms and moulds
K. Plantae - eukaryotes, multicellular, aka plants
K. Animalia - eukaryotes, multicellular, aka animals

Scientists often use a dichotomous key to help them identify species that they do not recognize.  A dichotomous key always gives the user 2 choices to choose between at each step until the species is identified.


Topic 2 - Viruses


The study of viruses is called virology.

Viruses aren't classified in the traditional sense, because they are on the border of living and non-living.

Not living:  They are not cells and they cannot metabolize
Living:  They can reproduces (but they need the help of a host cell!!)

Since they only show life functions in a host cell, we call them obligate parasites.

Structure
20-300nm large
inner core of nucleic acid (DNA or RNA)
outer protein coat (aka capsid) - exist in a variety of shapes (cylindrical, spherical, polyhedral, etc)
viral envelope (sometimes)

Image from: www. nutritionwonderland.com


Image from:  www.heartcurrents.blogspot.com 

Image from: www.armageddononline.org

Grouping (or classification) is based on viral shape, kind of nucleic acid and the host that is affected

Replication (Lytic cycle)
1.  ATTACHMENT: recognizes and attaches to receptor site on cell membrane.
2.  ENTRY:  sometimes just the nucleic acid is "injected" into the cell, sometimes the whole virus enters the cell.
3.  REPLICATION:  reprograms host cell to produce capsids and viral nucleic acids
4.  FORMATION:  nucleic acids and capsids are assembled.
5.  LYSIS and RELEASE:  the host cell bursts and releases new viruses into the environment.

Virulent viruses kill host cells.
Temperate viruses don't kill immediately:  their nucleic acid builds into the host's nucleic acids and replicates with the host's DNA.  Something triggers the virus to become virulent and then it enters the lytic cycle.  HIV and herpes are these kind of viruses.

Viruses are NOT killed by antibiotics
VACCINES can prevent some viral diseases and help to prevent epidemics (jarvany)

Examples of viral diseases:  influenza, rubeola, measles (kanyaro), tick-born encephalitis, hepatitis, rabies, polio, smallpox, chicken pox

Viroids and Prions (weird stuff!)

Viroids are short, single-stranded RNA, with no capsid.  They infect plants (eg. potato, coconut, etc) causing virus-like symptoms.

Prions are glycoproteins which are capable of reproducing in mammal cells, even though they have no nucleic acids!  They cause diseases like kuru and BSE (bovine spongiform encephalopathy)

Topic 3 - Kingdom Monera

-also known as bacteria

Structure
- unicellular, but some form colonies or filaments
-prokaryotes (no membrane-bound nucleus or cellular organelles)

Size
1-10 micrometers

Reproduction
- asexual:  binary fission, in good conditions a bacteria can copy itself every 20 minutes!

Image from :  http://web1.stmaryssen-h.schools.nsw.edu.au/SMSHS/ricks%20sites/Biology%20web%20site/HSC_9_4%20search%20for%20health/Chapter10_overview/disease_causing_organisms_files/reproductionofbacteria.htm 

- sexual:  conjugation
I
Image from:  http://commons.wikimedia.org/wiki/File:Bacterial_Conjugation_en.png

Occurrence
EVERYWHERE!  Can be found in soil, air, water, even extreme environments.
Why?
1.  small and simple
2.  rapid reproduction (adapt quickly to changes)
3.  less specialized (adapt quickly to changes)
4.  slimy, thick capsule and cell wall (great protection)
5.  can use "poisons" (or things humans consider poisonous!)
6.  can form endospores (survive freezing, boiling, drying, radiation and chemicals)

Nutrition
1.  Autotrophs (self-feeders)
a) photoautotrophs can produce food for themselves through photosynthesis.  So they use the energy from the sun to produce sugar.
b) chemoautotrophs can produce food for themselves through chemosynthesis.  So they use chemical energy from the oxidation of inorganic molecules (like hydrogen sulfide) to produce sugar.

2.  Heterotrophs (fed by others)
a) consumers (fogyasztók)
b) parasites - pathogens (kórokozók), they cause disease (eg. Lyme's disease, tuberculosis, salmonella, tetanus)
c) saprotrophs - feed on dead things, also called decomposers (lots found in soil and oceans)
d) mutualists/symbionts - live together with another organism and each provides a "service" to the other (eg. E. coli and humans, cyanobacteria and fungi=lichens)


Respiration
1.  Aerobe:  an organism which requires oxygen.  Releases the energy found in food in a process called cellular respiration
2.  Anaerobe:  an organism which doesn't need oxygen.  Releases the energy found in food in a process called fermentation. They are commonly found in soils (facultative), lake sediments (obligate) and are used in sewage treatment plants to digest sewage sludge.

Classification
1.  Archea (ősbaktériumok): often found in extreme habitats
- newer classification now places the Archea as a separate group from the bacteria, because they seem to have a different evolutionary history.  For a long time they were considered part of the bacteria, but no longer!  Physically they resemble bacteria, but their genes seem to be more closely related to eukaryotes (still they don't have a nucleus) 

2.  Eubacteria (valodi bakteriumok)
- classified by shapes: cocci (spheres), bacilli (rods), spirilli (spirals)

 - this group contains the bacteria that cause most human bacterial diseases.  Most can be either prevented by vaccines, or treated with anti-biotics
-most bacteria DON'T cause disease!!

E. coli

 Bacterial colonies on a plate

3.  Cyanobacteria (aka blue-green algae, but they aren't algae!) (kékalgák, kékmoszatok)
-autotrophs with bluish-green pigments in cytoplasm
-live in ponds, streams, lakes, moist land
-long chains (filaments) - slimy
-can cause "algal blooms"
Importance
-huge diversity:  producers (make oxygen), consumers, decomposers (keep the cycle of life flowing)
-biotechnology:  fermentation, antibiotics, hormones, insect pest control, sewage/chemical breakdown, genetic research and engineering




Extra credit project:  Make your own yogurt.  See the extra credits tab.

Topic 4 - Kingdom Protista


- eukaryotes:  have membrane-bound organelles.  The nucleus is the biggest organelle
-there are about 200 000 species in this kingdom
-most live in aquatic, marine or moist conditions
-very diverse - 3 groups: animal-like, plant-like and fungus-like

1.  Fungus-like
eg.  slime molds (nyálkagomba)
-saprotrophic
-multicellular
-share protist and fungal characteristics

2.  Animal-like
-Phylum Protozoa
-unicellular
- 200-300 times larger than most bacteria
- nutrition:  parasites, predators, saprotrophs
-grouped by type of locomotion
a) Non-motile
-parasites
-eg. malaria (váltóláz) caused by Plasmodium
The infected red blood cell is full of small purple dots (those are the protist!)
Image from: tolweb.org/images/Plasmodium/68071


b) Amoebas (állábuak)
-move and feed with pseudopods (false feet)

Image from: shs.westport.k12.ct.us/mjvl/biology/biohome.htm


-includes hundreds of species
-engulf food by flowing around it.  Watch this!
-marine or aquatic, some are parasitic (eg. dysentery/vérhas)
-some have shells (extend pseudopod through holes in shell) - important in calcareous rock formation

c) Flagellates (ostorosok)
-move with flagella
-some are predators, some are parasites (eg. Trypanosoma, which causes sleeping sickness)
Image from:  www.eden.rutgers.edu/chrmccoy/paraspring10.htm

d)  Ciliates (csillósok)
-covered with cilia, move by beating cilia
-have 2 kinds of nuclei:  macronucleus to control cell life functions and micronucleus (1 or more) for reproduction
eg.  Paramecium (papucsállatka)




Here is a malaria jigsaw puzzle!

Osmosis - the movement of water across a selectively permeable (or semi-permeable) membrane from an area with low solute concentration to an area of high solute concentration.  This process doesn't require energy.  Osmosis is important in biology because many biological membranes are semi-permeable and most cells have higher concentrations of solutes inside them than in surrounding freshwater.
From: www.goldiesroom.org/Note%20Packets/06%20Transport/00%20Transport-WHOLE.htm
If you want to see a video, try this.
We talked about this as it related to contractile vacuoles in Paramecium

Plant-like Protists
-can be unicellular or multicellular (include algae, which look like plants, but they have no real roots, stems or leaves! - more on this later!))
-are phototrophs, so they photosynthesize.  To do this they must have pigments (green, red, brown and yellow can be found!), which are found in chloroplasts (zöldszíntest)
-have cellulose cell walls
- the microscopic ones form phytoplankton (plankton that can photosynthesize)
You can listen to a short radio program about phytoplankton (general information, not related to the course specifically).  Scroll down on the page until you reach the section on Fading phytoplankton.

Classification
1.  Euglenophyta (ostorosmoszatok törzse)
-unicellular
-aquatic
-mixotrophs:  autotrophic in light (photosynthesizes since it has chlorophyll - green pigments - in chloroplasts), heterotrophic (hunters) in dark
-store food as starch (plant-like characteristic)
-no cell wall, have pellicle (animal-like protist characteristic)

eg.  Euglena viridis (zöld szemesostoros)




-the red eyespot detects light, the euglenoids move towards the light to be able to photosynthesize
-flagella allow for active movement
-cytopharynx (missing from this image, but in your notes) and contractile vacuole are animal-like protist characteristics

2.  Yellow Algae, aka Diatoms (sarga vagy kovamoszatok)
-unicellular
-autotrophs - chlorophyll (green) and carotenoids (yellow)
-marine and freshwater
-silica shells (kovapáncél) - like little round jewellery boxes, radially symmetrical
-used for abrasives in toothpastes and polishes, added to paint to make it sparkle



3.  Green Algae (zöldmoszatok)
-most diverse group:  about 7000 species
-major pigment is chlorophyll (green), but also contain carotenoids
-have cellulose cell wall and store starch (plant-like)
-primarily freshwater, but also marine and can even be found in moist soil, on trees, in snow and in the fur of sloths (lajhár)!!
-ancient ancestor of simplest plants
-unicellular and multicellular (thalloids)




4.  Red Algae (vörösmoszatok)
-marine
-most are multicellular with 3-D thalloid bodies
-contain chlorophyll (green), phycoerythrins (red) and phycobilins (blue)
-can survive up to 200m deep because can photosynthesize with just green, blue and violet light
- uses: food, agar and food thickener


5.  Brown Algae (barnamoszatok)
-about 1500 species
unicellular and multicellular
-almost all marine, found in cool areas
-don't grow deep than 25m
-contain chlorophyll (green) and fucoxanthin (brown)
-the largest and most complex in the group (60-100m tall) are the kelp.  They form kelp forests (important marine habitat) and are also used as food.


kelp forest



Reproduction in Algae
-both asexual and sexual
Asexual
-fragmentation (in filamentous algae)
-halving (diatoms)
-spores

when asexual and sexual alternate during a lifetime, it is referred to as the life cycle

Alternation of generations (nemzedékváltakozás)
-this includes both sexual and asexual stages

The gametes are haploid (n) - this means they only carry 1 copy of the genetic information.  When they fuse they form a diploid (2n) zygote, which now has 2 copies of the genetic information.  This grows into a sporophyte.  A halving division called meiosis occurs, which produces haploid spores.  These spores grown into gametophytes, which are also haploid.  Gametophytes produce gametes and the cycle begins again.

Topic 5 - Kingdom Fungi


The study of fungi is called mycology

Characteristics
-found in moist,wet places
- have chitin cell walls
- store energy as glycogen (like animals)
- are decomposers

Structure
- some are unicellular (yeast)
 Electron microscope image of budding yeast

- most are multicellular - the cells line up to form hyphae (gombafonalok) and the hyphae branch and form mats, which are called mycelia (gombafonadékok)
 Light microscope image of mold (penész) mycelia

Nutrition
- heterotrophs : most are saprotrophs (they recycle nutrients), 
                          some are parasites (they have specialized hyphae, which grow into their host, these are called haustoria), 
                          some are mutualists (2 typical examples are mycorrhiza (fungi and plant roots) and lichens (fungi and cyanobacteria or green algae))
-extracellular digestion

Reproduction
Asexual: 
1) Fragmentation (breaking of hyphae)
2) Budding (found in yeast)
3) Asexual spores on sporangia

Sexual:
2 different (+ and -) hyphae meet, they fuse and a sporangium grows at this point.  Sexual spores form on this sporangium, they are highly resistant. 


Classification

1.  Zygomycetes (moszatgombák)
- examples are black bread mold and peronospora
Black bread mold (Rhizopus)
Peronospora on a grape leaf
- no branching of hyphae
-mostly saprotrophs (peronospora is one of the few parasites)
-will reproduce asexually if there is enough water and food
-if water or food is limited, then they will reproduce sexually, to produce resistant sexual spores, which are called zygospores
 
2. Ascomycetes (tömlős gombák)
-these are also called sac fungi
-some are unicellular (yeasts), others are multicellular with branching hyphae (mycelium)
-the sexual spores (ascospores) are found in sac-like cases called asci (ascus is the singular)
-this is the largest group of fungi with the most variablility
-examples include: yeast (élesztők)

penicillium (from which the antibiotic, penicillin, was derived)

ergot


powdery mildew (lisztharmat)


cup fungi (csesze gomba)

morels (kucsma gomba)

3.  Basidiomycetes (bazídiumos gombák)
-examples include:
mushrooms (kalapos gombák)




puffballs (pöfetegek)

bracket fungi (tapló gombák)

rusts


smuts


-sexual spores (basidiospores) are found in the basidium (sporangium), usually in the cap of the fungus, on the gills (lemezek)
-there is no asexual stage in this group

Lichens (zuzmók)
- an obligate symbiosis of fungal mycelia and cyanobacteria or green algae
- the fungal mycelia:
provide a structure that secures the lichen to a surface
 prevents the photosynthetic partner from drying out
uptake water and minerals from the environment
- the cyanobacteria or green algae:
photosynthesize
-can be red, yellow, orange, grey or black
-they can be crusty, foliose, shrubby
- only reproduce asexually
- classification unclear (neither really fungus, nor algae, nor bacteria!)
-they are pioneer species:  first to enter an uninhabited area (wide range of tolerance), slowly break down rock (acid production, mycelia boring into cracks, create humus when they die)
-they are indicator species: they are very sensitive to chemical pollution, eg. sulphur dioxide