Download
1 / 71
E N D
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)
27) Know your evolution terminology • 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
Indian Spectacled Monkey Humans did not come from Monkeys! (We do share a common ancestor.)
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.
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 human appendix vestigial limbs in snakes
ALSO: Some Biochemical Evidence For Evolution All organisms have DNA (& RNA) All organisms have ATP Similarities in cell respiration enzymes
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.”
phylogenic tree – demonstrates evolutionary relationships Phylogeny looks at evolutionary history in classifying organisms.
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.
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.)
28) What is Binomial nomenclature • Homo sapien • Genus & Species Identifier • Ursus arctos
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
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?
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
He devised a system of grouping organisms into hierarchical categories. (Taxa) He used structure and form of organisms (morphology) to help classify them. ALSO:
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:
ALSOThe 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:
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.
Eubacteria v. Archaebacteria • 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.
Bacteria Diseases • leprosy, tuberculosis, Lyme disease, anthrax, tetanus, form of pneumonia, strep throat, etc. • Various forms of food poisoning
Also antigens and antibodies • Plasma cells produce antibodies. Antibodies – Y shaped with two identical arms. They attach to antigens (proteins present on foreign cells etc.
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.
33) Distinguish between temperate and virulent viruses. 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.)
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.
34) What is a retrovirus? An RNA virus that uses reverse transcriptase to reproduce. (Such as HIV or Influenza)
35) Some Viral Disease: • Colds, Influenza, AIDS, hepatitis, chicken pox, measles, small pox, viral pneumonia, rabies, polio, mumps, etc.
37) Know some protist vocabulary Endocytosis 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)
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.
38) Contractile Vacuoles 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.
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 the rear (posterior). The canals fill with fluid, which discharge into the central vacuole. The vacuole then ejects the fluid from the cell.
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
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.
40) ANIMAL terminology Animals are multicellular, eukaryotic, heterotrophs
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)
Protostomes– “first mouth” spiral cleavage of developing embryo, blastopore becomes the mouth, second opening becomes the anus (occurs in most animal phyla).
monoecious and dioecious • Monoecious – (“One House”) hermaphroditic animals – both male and female sex organs • Dioecious – (“Two Houses”) separate sexes
Primary Germ Layers:- • result of gastrulation, three primary layers
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.
pseudocoelomate – “false body cavity” mesoderm lines an endodermic gut suspended in a fluid filled coelom cavity.
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.
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.
