Download - Topic 1: Classification
• Taxonomy: Branch of biology that groups all life according to their characteristics and history
• All life on earth is placed into 1 of 6 kingdoms:– Eubacteria– Archaea– Protista– Fungi– Plants– Animals
• Developed classification system based on physical features
• Binomial Nomenclature: System of giving every organism 2 names– 1st word: Genus (broad)– 2nd word: Species (specific)
• Example: House cat– Genus: Felis (cougars, lions,
tigers, cheetahs, etc…)– Species: catus
• When Writing:–Genus capitalized–species lowercase–Underlined entirely
Ex: Homo sapiens
• When Typing:–Same, except use italics
Ex: Homo sapiens
• 7 individual levels (taxa) used to classify organisms Kingdom (broadest) Phylum Class Order Family Genus Species (specific)
• Allows relationships to be clearly seen
The more levels in common...the more related the species.
• Taxonomy: grouping life according to shared traits (not just physical)
• 1) Morphology: studying the form and structure of organisms– Comparing the
morphology (traits) of different species shows similarities and/or differences
Morphology Shows Non-Relationships Also!
• Comparing DNA, amino acids, & proteins
• DNA mutations occur at known rates–Splits in evolution can be
estimated based on how different DNA between 2 organisms is
–More different the DNA…longer ago common ancestor
• Patters of development studied to identify relatedness• Blastopore (1st opening of embryo) shows humans &
starfish are more related than humans & squid
Mouth Anus Anus
• Defined: Evolutionary history of an organism• Shown by cladograms
– Group life according to similaritiesHow many traits does a primate & amphibian share?Which organisms do not have amniotic eggs?
all have amniotic eggs
• Virus: A biological particle composed of nucleic acid and protein
• Intracellular Parasites: organism that must “live” inside a host
Topic 2: Viruses
• Reproduce• Have nucleic acid• Adapt to
surroundings• Have organization
• Not made of cells or organelles
• Can’t reproduce on own• Don’t metabolize energy• Don’t perform cellular
processes
Are viruses alive?
• All Have:–1) Capsid: coat of
protein that surrounds nucleic acid
–2) Nucleic Acid: RNA or DNA
• Some Have:–Tail Fibers: Used for
attachment (not legs)• Shapes vary
1st Step: Attachment– Virus attaches to a cell receptor– No attachment = No infection
2nd Step: Entry– Virus enzyme weakens cell membrane– Genetic material (DNA or RNA) enters host cell
3rd Step: Replication– Virus DNA/RNA makes virus proteins by transcription/
translation
4th Step: Assembly– New virus proteins are assembled into new viruses
5th Step: Release– Virus enzyme causes host to burst– Viruses are released to find new host…Cycle repeats
Host cell
DNA
Pro-phage
1) Attachment: Virus attaches to host cell
2) Entry: Virus nucleic acid enter the cell, but combines with host cell DNA.
Pro-phage
Pro-phage
Pro-phage
The host cell divides by mitosis, making a copy of the prophage each time.
Two infected cells.
Pro-phage
Pro-phage
Two cells divide my mitosis to make 4 infected cells.
Four infected cells divide by mitosis to make 8…and so on….
Virus DNA eventually becomes active and starts to create viruses following the stages of the lytic cycle.
All infected cells burst, releasing many more viruses to restart the cycle.
• Prokaryote– Cells w/o nucleus & membrane
bound organelles– Chromosome & plasmids float
freely in cytoplasm• Ribosomes
– create proteins• Flagella
– used in movement• Pili
– act as anchors– Connect to other cell during
conjugation • Endospore
– “cocoon” to protect DNA in harsh times
• Many bacteria grow in colonies
• 3 Basic Shapes:
• 1) Rod• 2) Spherical• 3) Spiral
Bacteria Asexual Reproduction
• Binary Fission: asexual reproduction where one cell splits into two cells– Both cells have identical sets of DNA– Less genetic diversity
Click pic
Bacteria Sexual Reproduction
• Conjugation: process where DNA is exchanged between bacteria cells
• Cells connect by pili• DNA duplicated and then exchanged• Creates genetic diversity
Gene to resist ampicillin Gene to resist ampicillin
• Anaerobic– Obligate anaerobic = cannot live in oxygen
• Aerobic– Facultative aerobic = can live with or without oxygen– Obligate aerobic = must live in oxygen
The bacteria that causes TB lives in your lungs…which type is it?
Identifying Bacteria with Gram Staining
• Gram negative:• stains pink• extra outer layer• harder to treat
• Gram positive:• stains purple• lack extra covering• easier to treat
HEALTHY GINGIVITIS
MODERATE PERIODONTITIS ADVANCED PERIODONTITIS
Topic 4: Protista
Protista in General• Usually unicellular• Reproduction:
– Asexual, Sexual, Both• Kingdom for life that
doesn’t fit in animals, plant or fungi kingdom
• Mostly aquatic life• 3 main categories based on
feeding– Animal-like– Plant-like– Protista-like
Animal-Like Protista (Protozoans)• Aquatic, unicellular• Heterotrophic
– Feed & ingest prey– pathogens, parasites,
predators– 3 subcategories based on how
they move
• 1) Pseudopods : have pseudopodia (false- feet)– Engulf by phagocytosis
• 2) Flagellates: have flagella• 3) Ciliates: have cilia
Pseudopod (Amoeba) feeding
Pseudopod Video Clips
File title: Amoeba2 File title: Amoeba4
Ciliates Video Clip
File title: Paramecia2 File title: Rotifer2
Flagelletes Video Clip
File title: Euglena2 File title: Euglena
Animal-Like Protista & Disease
• Malaria: Infected mosquito bites– Fever, vomiting,
coma, death• Sleeping sickness:
bite of tsetse flies– Coma & death
Plantlike Protista• AKA: Algae• Perform photosynthesis with
chloroplasts– Provide ~ ½ the O2 on earth– Most unicellular– Phytoplankton: basis of aquatic
food chains (producers)• Few multicellular
– Seaweed, kelp• Why not plants?
– No true leaves, stems, or roots– most unicellular
Fungus-like Protista• Heterotrophs
– Decomposers: recycle nutrients– Absorb nutrients
• Moist environments• Slime Molds: large (~1 meter)
single celled mass of cytoplasm
• Water molds: can be parasitic– Potato blight: disease & the Irish
potato famine
Fungi Structure & Basics
• Hyphae: thin strands of cells that make up the fungus body– Hyphae spread into a larger mass (mycelium)
• Fruiting body: Above-ground reproductive structure• Cell wall of chiton (common to animals)• Heterotrophs: hyphae release enzymes to absorb nutrients• Classification determined by sexual reproduction methods
Zygote Fungi• Bread Molds• Some help “fix” nitrogen in
atmosphere• Asexual Reproduction
– Sporangia produce spores– Spores can grow into new
hyphae when released
...
Hyphae grow into a mat of mycelium
Sporangia release spores
.. .
ground
Haploid spores land
Sporangia grow from the mycelium
.. .
ground
The process repeats
Zygote Fungi
• Sexual reproduction– Hyphae from 2 organisms
fuse and form a diploid zygospore
– Zygospore grows new hyphae when released
ground
Spores land
Hyphae grow into a mat of mycelium
Hyphae of fungus #1 Hyphae of fungus #2
Hyphae of fungi grow together
Diploid zygospore is created
New diploid hyphae grow from the zygospore
Hyphae grow into a mat of mycelium….
Sporangia release spores
.. .
ground
Sporangia grow from the mycelium
ground
The cycle repeats
Hyphae of fungus #1 Hyphae of fungus #2
.. .
ground
Club Fungi
• Basidia: club-like structure that produces sexual spores (located in gills underneath)
• Hyphae of two individuals grow into mycelium• Fruiting body created to make spores
Club Fungi
ground
Fungus #1 mycelium grows underground….Fungus #2 mycelium grows underground
Diploid fruiting body grows from the mass
Haploid spores created & released from the underside of the fruiting body
. . . . .Two fungi grow together and fuse
Spores will land
ground
Spores will land
New hyphae will grow into a new mycelium
Cycle repeats
Sac Fungi
• Ascus: sac that contain spores during sexual reproduction
• Two hyphae grow together to create fruiting body• Spores released• Ex: Yeast, morals, truffles
ground
Fungus #1 mycelium grows underground….Fungus #2 mycelium grows underground
Diploid fruiting body grows from the mass
Haploid spores created & released from the ascus
Two fungi grow together and fuse
Spores will land
ground
Spores will land
New hyphae will grow into a new mycelium
Cycle repeats
Lichens
• Fungus + blue-green bacteria or green algae• Mycelium of fungi surrounds the green organism• Grow on rocks (pioneer species), soil, trees• Mutualistic relationship
– Algae/bacteria: obtains warmth, substrate to grow in– Fungus: obtains food
• Food source & help create soil during succession
Topic 6: Plants
Plant Evolution• Evolved from green algae
(450 mya)• Green algae ancestor
– Multicellular body– Cells w/ channels to
communicate– Reproduce w/ sperm &
egg• Early plants
– Low growth (nonvascular)
Land Adaptations
• Retain Moisture– Early plants grew near waters edge– Cuticle: waxy coating
Land Adaptations
• Transporting Resources– Vascular system: tissue to transport nutrients
• Up from the roots (ex: water)• Down from the leaves (ex: sugars)
– Allows taller growth
Land Adaptations
• Growing upright– Large plants need to support own weight– Lignin: hardens cell wall; gives wood strength
Land Adaptations
• Reproduction on land– Pollen: carried by wind/animals– Seeds: hard coat protects embryo inside
Alternation of generations (In general)• Diploid zygote created• Diploid zygote grows into
a diploid sporophyte• Haploid spores created by
meiosis• Haploid spores grow into
haploid gametophytes– Male gametophyte creates
haploid sperm– Female gametophyte
creates haploid egg• Sperm and egg fuse to
make a diploid zygote• Cycle restarts
Group 1: Seedless, Nonvascular Plants
• Live in moist environments to reproduce
• Liverworts• Hornworts• Mosses
Group 1: Seedless, Nonvascular Plants• Mosses
– Grow low to ground to retain moisture (nonvascular)
– Lack true leaves– Common pioneer
species during succession
– Gametophyte most common (dominant)
Moss Life Cycle
gametophyte
1)Moss gametophytes grow near the ground (haploid stage)
2) Through water, sperm from the male gametophyte will swim to the female gametophyte to create a diploid zygote
3) Diploid sporophyte will grow from zygote
4) Sporophyte will create and release haploid spores
.....sporophyte
eggegg
egg egg
malemale male malefemalefemalefemalefemale
zygotezygo
te
zygote
zygote
5) Haploid spores land and grow into new gametophytes
groundgametophyte
6) The process repeats
gametophyte
.....sporophyte
eggegg
egg egg
malemale male malefemalefemalefemalefemale
zygotezygo
te
zygote
zygote
Group 2: Seedless, Vascular Plants• Vascular system allows
nutrient transport to greater heights
• Live in moist environments to reproduce
• Club mosses• Horsetails• Ferns
Group 2: Seedless, Vascular Plants
• Ferns– Vascular: allows taller growth– Haploid spores (meiosis) on underside of fronds– Spores grow into gametophyte– Sperm & egg create a zygote
Fern Life Cycle
AdultSporophyte (diploid)
...
.
1) Sporophyte creates and releases haploid spores
ground
ground
2) Haploid spores land in the soil
ground
3) From the haploid spores, gametophyte grows in the soil
Let’s zoom in
4) Sperm swim through water from the male parts (antheridium) to the female parts (archegonia)Let’s zoom back out
eggegg
egg
zygote
zygote
zygote
ground
5) Diploid sporophyte grows from the zygote
sporophyte
6) Fronds uncurls into leaves.
ground
7) Cycle repeats -- Haploid spores created and released
..
..
ground
Haploid spores land in the soil
ground
From the haploid spores, gametophyte grows in the soil
Let’s zoom in
Sperm swim through water from the male parts (antheridium) to the female parts (archegonia)Let’s zoom back out
eggegg
egg
zygote
zygote
zygote
ground
Diploid sporophyte grows from the zygote
sporophyte
Fronds uncurls into leaves.
ground
Cycle repeats
..
..
Seeds and their advantages• 1) Seed plants don’t depend
on water to reproduce– Pollen (contains sperm)
combines with egg– Egg hardens into a seed
• 2) Nourishment and protection– Nourish: Nutrients inside
seed for the embryo– Protection: Hard shell
• 3) Allow dispersal– Carried by wind, water,
animals
Group 3: Seed producing, Vascular Plants
• Type 1: Gymnosperms• Seeds not enclosed in a
fruit– produced inside cones
• Cone = reproductive structure
• Male cones: produce pollen
• Female cones: produce eggs and seeds
Group 3: Seed producing, Vascular Plants• Gymosperm example:
Conifers– Cone plants– Needle-like leaves– Common to lumber
industry– Evergreen, Pine,
Redwood, Cedar
Conifer Life Cycle
1) Male and female seed cones grow in adult sporophytes
2) Pollen grains released from the male seed cones-- Pollen is the male gametophyte
eggzygote
egg egg
egg
zygote
zygote
zygote
Male cones make pollen Female cones make eggs
3) Seeds begin to harden inside the female cones
seed
seed
seed
seed
4) Seeds released
5) Seed will land
ground
6) Seedling grows into (sporophyte)…the cycle repeats
ground
1) Male and female seed cones grow in adult sporophytes
eggzygote
egg egg
egg
zygote
zygote
zygote
Male cones make pollen Female cones make eggs
3) Seeds begin to harden inside the female cones
seed
seed
seed
seed
4) Seeds released
5) Seed will land
ground
6) Seedling grows into (sporophyte)…the cycle repeats
ground
Group 3: Seed producing, Vascular Plants
• Type 2: Angiosperms (flowering plants)
• Flower = reproductive structure– Protects gamete and
fertilized eggs• Seeds enclosed in a fruit
– Fruit: Plant ovary– Often attract animals
to disperse the seeds inside
Fruit Production
• In the seed– Embryo– Food supply
• Surrounding ovary grows into a fruit
• Fruit attracts animals to eat and spread the seeds Fruit seeds in fox droppings
Angiosperm types(flowering plants)
• 2 groups: Monocots and Dicots (based on seed type)• Cotyledon: embryonic leaf• Monocots: embryo with 1 seed leaf• Dicots: embryo with 2 seed leaves
Angiosperm Life Spans• Three Life Span Types:• Annuals
– 1 year: Mature…produce seeds…die
• Biennials– 1st year: produces short stem,
low growth leaves, food reserves
– 2nd year: taller stem, leaves, flowers, seeds
• Perennials– Live for more than 2 years
Flowers• Reproductive structure
of flowering plants• Sepals
– outer ring of leaves– protection
• Petals– Inner ring of leaves – Brightly colored to
attract pollinators• Open petals & sepals
reveal male and female structures
Flowers • Female Carpel– Inner most part– Ovary: within the
base (female gametophyte)
– Stigma: sticky tip, collects pollen
• Male Stamen– Surrounds carpel– Anther: produces
pollen (male gametophyte)
Angiosperm Life Cycle
Pollen stick to animal or released into wind
Animal finds a new flower to feed on
Pollen transferred to the stigma….seeds develop
eggzygote
Flower petals start to fall off and dies
zygote
Fruit falls to ground
Animals eat fruit….seeds come out the other end…cycle repeats
seed
Pollen stick to animal or released into wind
Animal finds a new flower to feed on
Pollen transferred to the stigma….seeds develop
eggzygote
Flower dies
zygote
Fruit falls to ground
Animals eat fruit….seeds come out the other end…cycle repeats
seed
End of the Semester!