also: endosymbiosis smaller prokaryotes became incorporated inside larger prokaryotes. these smaller...

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Page 1: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts
Page 2: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

Also: endosymbiosis • Smaller prokaryotes

became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts inside eukaryotic cells.

The first cells were thought to be simple, prokaryotic,

anaerobic, and heterotrophic. (Bacteria cells)

Page 3: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

• acquired inheritance - Lamarck’s evolution theory that characteristics acquired in life (through use or disuse) could be inherited.

• natural selection – adaptations or traits that lead to a survival advantage that can make an organism better fit to survive and produce offspring

27) Know your evolution terminology

Page 4: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

Humans did not come from Monkeys! (We do share a common ancestor.)

Indian Spectacled Monkey

Page 5: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

• Homologous structures are features that originated in a shared ancestor. They have different mature forms, but develop from the same embryonic tissue. They are inherited from a common ancestor.

• Example – animal forelimbs have adapted to different environments but share the same basic pattern of development.

Page 6: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

• Vestigial structures - A seemingly functionless structure in a modern organism that was useful to an ancestral form. They are usually small and imperfectly developed, such as human appendix, and pelvic bones in a snake

vestigial limbs in snakes

human appendix

Page 7: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

ALSO: ALSO: Some Biochemical Some Biochemical Evidence For EvolutionEvidence For Evolution

All organisms have DNA (& RNA)

All organisms have ATP

Similarities in cell respiration enzymes

Page 8: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

Descent with modification implies that all living organisms are related to one

another. (Darwin reasoned that if we look back far enough, we can find common ancestors to all living things. This is known as the “principle of common descent.”

Page 9: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

phylogenic tree – demonstrates evolutionary relationships

Phylogeny looks at

evolutionaryhistory in

classifying organisms.

Page 10: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

ALSO

Page 11: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

PRIMATE CHARACTERISTICS

(prosimian primates – resemble early forms such as lemurs, & tarsiers.)

“Primates have grasping

(prehensile)hands, & acute vision

Unlike most mammals,

primates have color

vision. They have

front-facing eyes,

and overlapping fields

of vision – All air primates in forest living.

Page 12: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

This gives primates depth perception, a

useful trait for an animal that moves by

swinging or jumping from branch to

branch. (An adaptation for life in the

trees.)

Page 13: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

28) What is Binomial nomenclature• Homo sapien

• Genus & Species Identifier

• Ursus arctos

Page 14: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

ALSO: Why do scientists avoid using common names when discussing

organisms?

Common names can be confusing because they may vary among languages and even among regions in a single country.

Example: A cougar • is a puma, • is a mountain lion• is a catamount

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29) What is a Dichotomous Key

• A tool biologists can use to identify an organism through a series of pared choices in a flow-chart type method. Each pair of choices is a dichotomy which usually describes various morphological characteristics.

Too Simple?

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30)

Page 17: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

Six Kingdom System:• Archaebacteria = unicellular prokaryotes

(descended from & very similar to first cells)

• Eubacteria = unicellular prokaryotes (most bacteria that affect you)

• Protists = protozoans & algae

• Fungi = fungi

• Plantae = plants

• Anamalia = animals

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He devised a system

of grouping organisms

into hierarchical categories.

(Taxa)

He used structure and form

of organisms (morphology)

to help classify them.

ALSO:

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Aristotle’s Classification Scheme

Plants were divided into three groups: herbs with soft stems, shrubs, and trees with a single wood stem.

Animals were divided into land dwellers, water dwellers and air dwellers.

ALSO:

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ALSO The Domain system proposes that a common ancestor cell gave rise to three different cell types, each representing a domain.

The three domains are the Archaea (archaebacteria), the Bacteria (eubacteria), and the Eukarya (eukaryotes).

The Eukarya are then divided into 4 kingdoms: Protists, Fungi, Anamalia, and Plantae. A description of the three domains follows:

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31) The basic bacterial shapes: coccus, bacillus, spirillum

Page 23: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

Benefits of Bacteria• Bioremediation, produce chemicals, antibiotics,

genetic engineering, fix nitrogen, recycle nutrients (decomposers), produce vitamins, digest food (cellulose for herbivores), produce some foods, block out some pathogens, etc.

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• Eubacteria are prokaryotes that have a peptidoglycan in their cell walls and lack introns in their DNA.

• Archaebacteria are prokaryotes that lack peptidoglycan and have DNA segments similar to those found in Eukaryotic cells (introns). They have unusual lipids in their cell membranes. They can be found in extreme environments---although their is evidence that they may occur in less severe conditions.

Eubacteria v. Archaebacteria

Page 25: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

Bacteria Diseases

• leprosy, tuberculosis, Lyme disease, anthrax, tetanus, form of pneumonia, strep throat, etc.

• Various forms of food poisoning

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Also

Page 27: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

antigens and antibodies

• Plasma cells produce antibodies. Antibodies – Y shaped with two identical arms. They attach to antigens (proteins present on foreign cells etc.

Also

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32) viruses: • What is chemical comprises the core of a virus?• DNA or RNA• Why are Viruses are said to be “obligate

intracellular parasites” ? • They must reproduce in a host cell, which

eventually dies. • What is a bacteriophage? • A bacteriophage is a virus that infects

bacterial cells.

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The lytic cycle?•A phage reproduces by the Lytic cycle in which it attaches to a cell, injects its genes, and causes the bacteria to become a virus factory, producing new viruses.

(Virulent viruses reproduced in the Lytic cycle.)

33) Distinguish between temperate and virulent viruses.

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The Lysogenic Cycle• A virus that replicates through the

lysogenic cycle does not kill the host cell immediately. It may stay in the host for days, months or even years.

• The virus in this cycle is called a temperate virus.

• The virus DNA is incorporated in the cell DNA, at a site in the host cell genome, is called a prophage. (provirus) The prophage is replicated with the cell DNA and is passed to daughter cells.

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34) What is a retrovirus?

An RNA virus that uses reverse transcriptase to reproduce. (Such as HIV or Influenza)

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34)

Page 34: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

37) Know some protist vocabulary

The cell membrane folds in to form a small pouch which pinches off within the cell to form a vesicle.

Exocytosis (the reverse of endocytosis)

Endocytosis

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Two major types of endocytosis: • pinocytosis – transport of solutes or fluids• phagocytosis – movement of large particles or

whole cells. Unicellular organisms such as the amoebae can ingest bacteria and other protozoans, such as paramecia.

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Page 37: Also: endosymbiosis Smaller prokaryotes became incorporated inside larger prokaryotes. These smaller organisms eventually became mitochondria and chloroplasts

Excess water removal: Due to the hypotonic conditions of the surrounding environment, the freshwater sarcodines must constantly rid themselves of excess water that diffuses into the cell.

Most freshwater sarcodines expel water with an organelle called a contractile vacuole.

38) Contractile Vacuoles

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Excess water removal: Paramecia use contractile vacuoles near the surface on the side opposite the oral groove, one at the front end (anterior) and one at therear (posterior).

The canals fill with fluid, which discharge into thecentral vacuole. The vacuole then ejects the fluid fromthe cell.

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39) Protozoan Diseases

• Malaria – Caused by the sporozoan plasmodium (mosquito vector) Fever, chills etc.

• Amoebic dysentery – Cause by the sarcodine Entamoeba hystolytica –(water) diarrhea, cramps

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Giradiasis – Caused by a trypanosome from the phylum Zoomastigina (a zooflagellate) Water borne - diarrhea, cramps

African Sleeping Sickness – also caused by a trypanosome. (Tsetse fly -vector) Lethargy, mental deterioration, coma etc.

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40) ANIMAL terminology

Animals are multicellular, eukaryotic, heterotrophs

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Deuterostomes & Protostomes:

Deuterostomes – “second mouth” radial cleavage of developing embryo, blastopore (indentation of the blastula) becomes the anus, second opening becomes the mouth. (examples - echinoderms – such as star fish, chordates and vertebrates as well)

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• Protostomes – “first mouth” spiral cleavage of developing embryo, blastopore becomes the mouth, second opening becomes the anus (occurs in most animal phyla).

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monoecious and dioecious

• Monoecious – (“One House”) hermaphroditic animals – both male and female sex organs

• Dioecious – (“Two Houses”) separate sexes

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Primary Germ Layers:-

• result of gastrulation, three primary layers

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• coelomate – true body cavity - An endodermic gut – is surrounded & supported by a body cavity of mesoderm. The mesoderm forms tissues or attachments for organs located in the true body cavity, such as the liver, lungs, etc.

Mollusks, arthropods, chordates, & echinoderms

are coelomate animals.

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• pseudocoelomate – “false body cavity” mesoderm lines an endodermic gut suspended in a fluid filled coelom cavity.

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41) ANIMALS - INVERTEBRATES• Porifera - pore animals – sponges, filter

feeders, sessile (stationary), hermaphroditic, no true tissues, no symmetry, regenerates, aquatic, gemmules (buds)

Water enters the incurrent pore and leaves the sponge through the osculum. Collar cells draw in water with their flagella.

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• Cnidaria - stinging animals - jellyfish, hydra ,coral, anemone, aquatic, sessil – polyps, or medusa form (jellyfish),

• stinging cells in tentacles, gastrovascular cavity, soft-bodies, radial symmetry, statocyst – gravity detection, ocelli – eyespots, asexual and sexual reproduction.

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• Coral secrete calcium carbonate exoskeleton.

• Hydra reproduce by budding.

• Coral share a symbiotic relationship with algae. Coral supply vital nutrients to the algae.

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• Worms • Platyhelminthes - Flatworms – such as planaria (class

turbellaria) - free-living, acoelomate, bilateral symmetry, Fluke (class trematoda) Fluke (class trematoda) –parasitic, Tapeworm (class cestoda) segmented worm –

parastic.

• Nematoda round worms –pseudocoelomate – some are intestinal parasite such as ascaris – digestive tract , hookworms –anemia of blood, filarial worms elephantiasis, trichina worm – trichinosis

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• Annelida - Earthworms, marine worms – Earthworms have a true body cavity - coelom, all organ systems, and a closed circulatory system. They are hermaphroditic & can regenerate.

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• Mollusks - soft bodied animals - body divided into head-foot, and visceral mass, The mantle layer secretes the shell. The visceral mass houses organ systems. It has an open circulatory system.

gastopods – slugs,snailsbivalves – clams, oysters,

musselscephalopods – squid, octopus,

chambered nautilus

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• Arthropoda – jointed legs, exoskeleton molts to grow larger, protein & chitin, waxy outer layer, compound eyes, fused segments (tagmata), cephalothorax & abdomen, open circulatory system.

Crustaceans - crabs, lobsters, crayfish, shrimp, sowbugs, barnacles

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Arachnids - spiders, mites, ticks, scorpions, (spiders have book lungs, fangs called chelicerae, 8 simple eyes, and 8 legs.

Insecta - compound eyes, 6 legs, complete metamorphosis (egg, larva, pupa, adult)

and incomplete metamorphosis (egg, nymph, after successive molts - adult). They have specialized mouthparts. They reproduce quickly and in large numbers. Some maintain societies.

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• Phylum Chordata

• Subphyla:

Urochordata, Cephalochordata, & Vertebrata

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Characteristics shared by all chordates at some stage in their lives:

1) notochord -stiff rod of specialized cells, encased by a firm sheath along the length of the dorsal side. It becomes the vertebrate backbone

2)gill slits or pharyngeal pouches: seen in embryos, develop into gills in fish & other similar structures

3)dorsal hollow nerve cord : ( bundle of nerves runs down the back) above the notochord, the anterior end develops into the brain, & the remaining part becomes the spinal cord

4)post anal tail - Extension of the body past the anal opening - -- propels aquatic forms

notochord developmentin a zebra fish embryo

notochord in

a lancet

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42) Vertebrate animal phyla • Fish Classes- All ectotherms – cold-

blooded, 2 chambered heart, 1 loop of closed circulation, eggs in water, external fertilization.

Agnatha – Jawless fish (lampey and hagfish)

Chondrichthyes – cartilage fish

(sharks, skates & rays)

Osteichthyes –bony fish have scales,

swim bladder, lateral line & mucus coat

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• Amphibia - have metamorphosis, with an aquatic larval stage (gills), lungs and skin respiration, cold-blooded with webbed feet and no scales or claws & smooth moist skin.

(Apoda = legless Urodela =salamanders,

Anura = frogs and toads.)

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• Reptilia – rough skin with scales, claws, well-developed lungs, 3 – 4 chambered hearts, cold-blooded, Amniote “land” Egg (examples: alligators, crocodiles, lizards, snakes)

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• Aves – birds – warm-blooded (endotherms), eggs, 4 chambered heart, light-hollow bones, feathers, adaptations to flight.

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• Mammalia - warm-blooded –(endotherms –internal temperature regulation) 4 chambered heart, produce milk for their young, bodies covered with hair, specialized teeth.

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43) organs and structures • liver – produces bile, chemical detox., produce

glycogen, produce and breakdown cholesterol, etc.

• gall bladder – stores biles (to break up fat droplets)

• pancreas – produces digestive enzymes, as well as insulin

• kidney – filters waste from the blood (produces urine) regulates glucose in the blood

• small intestine- most digestion & absorption of nutrients

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• anther – produces pollen • ovary – produces egg cells• stigma – sticky to trap pollen• stamen – male portion of

flower supports the anther.

pollen grains 44) Flower structures

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ALSO: Organization of the plant kingdom

Seedless vascular plants

vascular plants seed plants

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Vascular Plants• As plants moved from water to land, they had to

adapt to retain water. Some early plants lived close to the ground.

• Plants developed a water-proof waxy cuticle layer. Eventually a vascular system developed to transport water and food throughout the plant.

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Non vascular plant • no true roots, stems or

leaves) They do not have a complex vascular system for moving food or water.

• They lie close to the ground or close to the bark of trees where they can rapidly absorb water.

• Non vascular plants are the Bryophytes.

Mosses are bryophytes

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Plant structures

vascular tissues of the plant:

Xylem carries water – made up of tracheids and vessel elements.

Phloem carries the products of photosynthesis, sugars, - made up of sieve tube elements and companion cells.

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Leaf internal structures

• cuticle layer – waxy layer -prevents water loss• mesophyll – ground tissue of chlorophyll-rich• parenchyma cells.

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• It consists of the palisade mesophyll and the spongy mesophyll. Spongy mesophyll has air spaces for water diffusion, and gas exchange. stoma – opening to allow gas exchange guard cells – control opening and closing of the stomata