The evolution of Complexity: single cell prokaryote to multicellular eukaryotes

Taxonomyclassifying organisms
Binomial nomenclature and scientific names
Canis lupus, Turdis migratoris, Felis catus
Systematics - the study of biodiversity and its classification, create phylogenies
Phylogenyan organism’s evolutionary history, a phylogenetic tree

• Domain
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species
Archea, Eubacteria, and
Eukarya
Archeabacteria, Eubacteria,
Protista, Fungi, Plant, Animal
First part of Scientific name
Second part of Scientific name

• Earth is approximately 4.5 billion years old
• 1 st living things, prokaryotic bacteria cells are found in the fossil record dating 3.5 billion years ago
• 1 st eukaryotic cells appear in fossil record dating 2.1 billion years ago
• Between 635-530 million years ago the fossil record shows the diversity of algae and small animal like organisms

• Spontaneous Generation: life from non-life was replaced with – Biogenesis
• Oparin’s hypothesis of the origin of life was tested by Miller and Urey, creating organic compounds but not life
• Endosymbiosis- the hypothesis behind the evolution of eukaryotes from prokaryotes

• What is a Virus?- nonliving…
Composed of genetic material, RNA or DNA, and a protein coat
Genetic material surrounded by a protein coat, must have a host cell in order to reproduce
Life cycles: Lytic (kills host cell) or
Lysogenic (incorporates DNA into host)

Virus- disease
• Flavivirus- Yellow Fever
• HIV- AIDS
• Herpes virus 3- Chicken pox
• Filovirus- Ebola
• Hepatitus B- Hepatitus
• Influenza virus- Influenza or pneumonia
• Epstien- Barr virus- Mono
• Polio virus- Polio
• Rhabdovirus- Rabies
• Voriola virus- Smallpox
• Paramyxovirus- Mumps

1. Archea
2. Eubacteria
3. Eukarya
Bacteria once belonged to the same Kingdom,
Monera, but through Molecular Biology and the study of evolution, Biologist realized they had critical differences and should be placed into their own category so the “Domain” classification level was created.

• Archea Kingdom
All prokaryotic single celled organisms.
No Peptidoglycan in cell wall
Most ancient and extreme
They live in the harshest environments
Methanogens (anaerobic), thermoacidophiles (hot) and halophiles (salty)
• Eubacteria Kingdom
True bacteria, all prokaryotic single celled
Have Peptidoglycan in cell wall
Classified by their shape and gram staining
Gram + have more peptidoglycan and stain purple
Gram – have less peptidoglycan and stain pink

• Sphere Cocci, can occur in chains Streptococcus
Pneumoniae which can cause strep throat or Scarlet fever, or grapelike clusters Staphylococcus aureus which can cause skin infections and Toxic Shock syndrome
• Rod Bacillus ex Escherichia coli (E.coli), Lactobacilli which can cause tooth decay or one strain makes
Sourdough bread, other bacilli can cause botulism, typhoid fever, and anthrax
• Spiral Spirilla comes in 3 shapes 1. Vibro which is curved caused Cholera, 2. Spirillum (thick spiral), and 3.
Spirochete (thin spiral) ex. Treponema pallidum causes
Syphilis and another strain can cause Lyme disease

Syphilis and Cholera
E. coli
Strep- chain
Staph - cluster

• Cyanobacteria - photosynthetic/producers, building blocks of most aquatic food webs
• Nitrogen- Fixing Bacteriasymbiotic relationship with plants, they help them absorb nitrogen from the soil.
• Helpful: fermentation, digestion, biotechnology, nitrogen fixing, decomposers, oxygen producers
• Antibiotics kill bacteria by destroying the cell wall, gram negative have an extra lipid layer that prevents the antibiotics from entering the cell.

• Bacteria reproduce asexually, binary fission
• Each bacteria has a single chromosome but can have additional DNA in the form of plasmids.
• Plasmids increase Bacterial genetic variation and contribute to Bacteria evolution
• Plasmids can be exchanged between different bacteria (even different species) by a process called conjugation.
• Plasmids can also be taken up by bacteria from their environment via transformation.
• Additional DNA recombination can be introduced via a bacteriophage, this is called transduction.

All bacteria:
• Reproduce asexually
• Single celled
• Have cell wall
• Single strand of DNA
Some Bacteria:
• Autotrophic
• Heterotrophic
• Some move by flagella, slime, spiral motion
• Some produce endospores which allow them to go dormant during hostile conditions
• Some produce toxins

• Kingdom of Mostly single celled organisms
• Categorized by their likeness to 3 other kingdoms
• All Eukaryotic some Autotrophic and some
Heterotrophic

•
•
•
•
•
•
• Algae or Plant-like, Autotrophic, classified by pigment with no cell wall, come form elaborate colonies and multicellular structures (kelp and seaweed)
Chrysophyta- Golden Algae ex diatoms
Pyrrophyta- bioluminescent/glow ex. Dinoflagellates
Euglenaphyta- ex Euglena
Rhodophyta- red
Phaeophyta- brown, seaweed and kelp
Chlorophyta- green, ex Volvox, Spirogyra

• Volvox
• Spirogyra
• Red algae
• Seaweed
• Kelp
• Diatoms

•
•
•
Protozoa or Animal-like, classified by mode of movement
Sarcodina
“false foot” ex. Amoeba- move by pseudopodia
Ciliophora ex Paramecium- move by
Zoomastigina ex Trypanosoma (African Sleeping
Sickness) moves by flagella cilia , tiny hairs
• Sporozoa , are the parasitic animal like protista, include Plasmodium which causes Malaria

• Amoeba
• Paramecium
• Trypanosoma

• Fungus-like are all
Heterotrophic with no cell wall, absorbing nutrients directly through cell membrane
• Include Plasmodium or Slime
Molds and Downy Mildews

• All Eukaryotic, multicellular, heterotrophs
( saprotrophs or detrivores living off dead and decaying organisms or decomposers), cell wall made of c hitin (type of protein), and classified by reproductive structures.
• Mycoses is the term for Fungal Infection,
Fungus destroys the cells around the infection site, to fight fungal infection you have to destroy the cell wall
• Fungi are important part of an ecosystem because they recycle nutrients/ decomposers

• Club Fungi – Basidiomycota , Basidia, ex
Mushrooms
• Sac FungiAscomycota, Asci, ex. Truffles,
Morels,Yeast, and Athletes Foot Fungus
• Zygote Fungi – Zygomycota, Sporangia, ex.
Bread molds
• Imperfect - Deuteromycota, reproduce asexually, ex Penicillian
• Lichen - Mycophycophyta, symbiotic relationship between fungus and photosynthetic cells of cyanobacteria or algae.

• Multicellular, Eukaryotic, Cell wall made of cellulose, Autotrophs, not capable of movement, reproduce sexually some produce spores and others seeds.
• Most have vascular tissues which include roots, stems, and leaves, and specialized tissues called xylem and phloem.

• Evolved from green algae, 400-450 mya
• Evidence: they both…
– Chlorophyll a, b, and carotenoids
– Thylakoid membranes
– Cell walls of cellulose
– Stored carbohydrates as starch
**Primitive plants were aquatic, but adaptations have allowed them to be successful on land.

• Adaptations to terrestrial life
– Cuticle (leaf)- keep water in
– Stoma (leaf)- control gas exchange
– Development of specialized tissues leaf, root, stem, root hairs, vascular tissue
– Symbiosis with fungi and bacteria to increase nutrient uptake
– Secondary growth- lateral meristem to thicken structures
– Spores and seeds not dependent on water

• The leaf
– Cuticle
– Stoma
- Vascular bundles
- mesophyll

2

Figure 10.20 A review of photosynthesis

3

Photosynthesis relies on CO
2 the leaf and O
2 entering leaving the leaf
Leaf surfaces contain stomata
Guard cells Pore Stoma
18 µm

Carbon dioxide diffuses into leaves through stomata
H
2
O
Leaf cross-section
CO
2
BUT: water also escapes through the stomata

2
2

AP Biology
ETC of Photosynthesis chlorophyll a
Photosystem II chlorophyll b
Photosystem I


Light reactions elevate electrons in
2 steps (PS II & PS I)

PS II generates energy as ATP

PS I generates reducing power as NADPH
ATP
AP Biology


If PS I can’t pass electron to NADP…it cycles back to PS II & makes more
ATP , but no NADPH
 coordinates light reactions to Calvin cycle

Calvin cycle uses more
ATP than NADPH
ATP
18 ATP + 
1 C
6
H
12
O
6


cyclic photophosphorylation
NADP
NONcyclic photophosphorylation
ATP
AP Biology


Photorespiration is a process in plant metabolism by which RuBP (a sugar) has oxygen added to it by the enzyme (rubisco), instead of carbon dioxide during normal photosynthesis

Photorespiration can occur when carbon dioxide levels are low, for example, when the stomata are closed to prevent water loss during drought. In most plants, photorespiration increases as temperature increases. Photorespiration produces no ATP and leads to a net loss of carbon and nitrogen (as ammonia), slowing plant growth.

Potential photosynthetic output may be reduced by photorespiration by up to 25% in C3 plants.
AP Biology

C
4 plants sequester CO
2 in certain cells
CO
2
Organic acid
C
4 pathway
CO
2
CO
2 stored in mesophyll cell
Calvin cycle
CO
2 used in adjacent bundle sheath cell
G3P
Examples of C
4 plants: corn, sugarcane, many grasses

Figure 10.18 C
4 leaf anatomy and the C
4 pathway

4

CAM plants sequester CO
2 at night
CO
2
Organic acid
C
4 pathway
CO
2 stored at night
CO
2
Calvin cycle
CO
2 used during the day
G3P
Examples of CAM plants: pineapples, cacti, and most succulents.

Photosynthetic adaptation to arid conditions evolved in many succulent, water-storing plants: cacti, pineapples

Figure 10.19 C
4 and CAM photosynthesis compared

9 Phyla of Plants: can be divided into spore or seed producers
Spore producers
• Bryophyta only nonvascular plants, ex moss and liverwort (gametophyte dominant stage of life cycle know as alternation of generations)
• Lycopodophyta ex. 1,000 species of Club and
Spike moss
• Pterophytes 12,000 species of ferns, horsetails, and whisk ferns have compound leaves called fronds (dominant stage is the sporophyte)

• Gymnosperms : reproductive structure is the cone , “naked seed”
– Cycadophyta 130 species of these tropical plants
– Ginkgophyta 1 species remains the Gingko tree
– Coniferophyta 600 species of conifers, pine, spruce, cypress, juniper, fir
– Gnetophyta 75 species of these arid/semidesert dwelling plants

Angiosprems - reproductive structure is the flower, seeds are surrounded by fleshy or dry fruit that ripen to encourage animals to disperse the seeds.
30,000 or more identified species maple, hickory, oak, aloe, roses, tulips, dogwood, magnolia, corn, beans, tobacco, apple tree, pecan tree
2 classes:
Monocots – with one seed leaf or cotyledon and parallel veins on the leaf, orchids, lilies, grass, corn, grains
Dicots with two seed leafs and branched veins on the leaf, roses, peas, beans, and oaks

“Cone Bearers”

• Produce flowers and fruits (fleshy or dry)

• Fruit is the mature ovary of the flower.
• It surrounds the seed and is often used to promote seed dispersal.
• Animals eat the fruit and seed and poop it somewhere else, this reduces competition with the parent plant.

• Pollination- fertilization of the female gamete by the male gamete
• Flowers are designed to attract a pollinator, either by color, smell, or offer of food.
• Birds, insects, and mammals act as pollinator

• Plants and Nitrogen fixing Bacteria
• Flower patterns and scent attract pollinators
• Fruits promote seed dispersal by offering a sweet reward to animals.

• Tropism- plant activities controled by hormones
– phototropism (light), geotropism (gravity), and thigmotropism (touch)
• specialized leaves (needles, spines, fuzzy, waxy) help reduce water loss in arid environments

multicellular, eukaryotic, no cell wall, heterotrophs, capable of movement, reproduce sexually, body symmetry (radial or bilateral)
9 Phyla- 8 invertebrate and 1 vertebrate

• Porifera- two cell layers, collar cells w/flagella, filter feeders, ex. sponges

• Cnidarians- Stinging cells (nematocytes), radial symmetry, simple nervous system only stimulus and response, central cavity only one body opening, ex. jellyfish, coral, hydra, sea anemone

• Plathyhelmenthes: flat worms, only one body opening, three cell layers,ex. Tapeworm, Fluke,
Planarian, Marine worms
• Nematode: round worms, first with two body openings, 3 cell layers, many parasitic,
Heartworm, Roundworm, Vinegar Eel
• Annelid: segmented worms, two body openings,
3 cell layers, beginning of circulatory system, and digestive system (crop), ex. Earthworm and
Leech

•
• Plathyhelmenthes
Annelid
Nematode

• soft body, more complex body systems developing, eyes and nervous system, levels of communication beyond stimulus and response
3 classes
• Gastropod (snails and slugs),
• Cephalopod (squid octopus cuttlefish and chambered nautilus),
• Bivalve (oyster, clam, mussel, scallop)

• Bivalves
Gastropods Cephalopods

• jointed legs, exoskeleton, body segments (head, thorax, and abdomen), metamorphosis
(complete or incomplete)
4 classes:
Insect -6 legs (ant, grasshopper, beetle, bee, wasp)
Arachnid -8 legs (spider, tick, horseshoe crab),
Crustacean -10 legs (shrimp, lobster, barnacles, crayfish)
Myrapods -many legs, centipede and millipedes

Characteristics: spiny skin, complex regeneration capacity, found only in marine environments, radial symmetry,
Examples: Sea urchin, Sand dollar, Starfish,
Sea cucumber

Chordate notachord, complex body systems, sexual reproduction (internal or external fertilization) 5 classes:
Fish
Amphibians
Reptiles
Birds
Mammals

• Fish, moist skin covered in scales, gills to breathe, 2 chambered heart, cold blooded,
3 types:
1. bony ex Trout, Salmon, Bass, Catfish,
Grouper, Tarpon.
2. jawless, ex. Lamprey and tunicates
3. cartilaginous ex. Sharks and Rays

• Amphibian, cold blooded, 3 chambered heart, born in water, develop lungs, smooth moist skin, ex. salamander, newts, frogs, and toads (only dry skin)

• Reptile, dry leathery skin with scales, cold blooded, most have a 3 chambered heart, amniote/terrestrial eggs, ex. Lizards, snakes, turtles, alligator, crocodile

• Bird, warm blooded, 4 chambered heart, hollow bones, body with feathers

• Mammal, warm blooded, 4 chambered heart, milk producers, body with hair/fur
• Placental (live birth), Marsupial (pouch) ex.
Kangaroo, and Monotremes (egg) ex
Platypus

Body structure and develpment

Fig. 32-2-3
Zygote
Blastocoel
Endoderm
Cleavage Cleavage Blastula
Eight-cell stage
Ectoderm
Gastrulation
Blastocoel
Blastopore
Gastrula
Archenteron
Cross section of blastula

Fig. 32-3
OTHER
EUKARYOTES
Choanoflagellates
Sponges
Other animals
Individual choanoflagellate
Collar cell
(choanocyte)

Fig. 32-7
(a) Radial symmetry
(b) Bilateral symmetry

Fig. 32-8
Coelom
(a) Coelomate
Digestive tract
(from endoderm)
Body covering
(from ectoderm)
Tissue layer lining coelom and suspending internal organs
(from mesoderm)
Pseudocoelom
Digestive tract
(from endoderm)
(b) Pseudocoelomate
Body covering
(from ectoderm)
Muscle layer
(from mesoderm)
Body covering
(from ectoderm)
Tissuefilled region
(from mesoderm)
Wall of digestive cavity
(from endoderm)
(c) Acoelomate

Fig. 32-9
Protostome development
(examples: molluscs, annelids)
Eight-cell stage
Deuterostome development
(examples: echinoderm, chordates)
Eight-cell stage
(a) Cleavage
Key
Ectoderm
Mesoderm
Endoderm
Spiral and determinate Radial and indeterminate
Coelom
Archenteron
(b) Coelom formation
Mesoderm
Coelom
Blastopore
Solid masses of mesoderm split and form coelom.
Blastopore Mesoderm
Folds of archenteron form coelom.
Anus Mouth
(c) Fate of the blastopore
Digestive tube
Mouth
Mouth develops from blastopore.
Anus
Anus develops from blastopore.

Innate:
1. Instincts - complex pattern of innate behaviors, reflexes, fight or flight, courtships, species recognition (language, song, flashes of pattern/light)
2. Territory - physical space needed for breeding, feeding, and shelter, organisms can expend a lot of energy defending territory some will fight to the death.
3. Migration - instinctive seasonal movement, response to a changing environment, includes hibernation (cold) and estivation (dry and hot)

:
• Habituation - animal repeats a successful behavior, and does not repeat an unsuccessful behavior, birds learn which moths are poisonous by color and avoid eating them after becoming ill or getting a bad taste. Deer return to the same grazing field when successful.
• Imprinting – salmon and turtles return to same stream or beach to lay eggs in which they hatched, the environment left an imprint or memory

• Mechanical - physical structures
• Chemical - stinging sensations, poisons, bad taste, paralysis
• Camouflage - color or pattern that blend into environment
– Disruptive- ex zebra
– Cryptic- ex chameleon and squid
– Countershading- ex Fish have light belly and dark back