Term
| What is meant by abiotic origin of life? |
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Definition
| Life on earth originated from some non-living sources which formed small organic molecules such as amino acids and nucleotides which eventually evolved into higher life forms. |
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Term
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Definition
| a self replicating molecule -- abiotically produced molecules surrounded by a membrane (or like structure.) |
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Term
Describe the simplest types of cell metabolism. |
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Definition
| If enzymes are included in the solution from which the droplets self assemble, some liposomes can carry out simple metabolic reactions and export the products. |
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Term
| How does the book define what life is? |
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Definition
| Defined by two properties - accurate replication and metabolism. |
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Term
How could natural selection act on even abiotic protobionts? |
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Definition
| Natural selection would have acted on the first molecules containing RNA, making RNA sequences of base pairs with better structure more successful. |
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Term
| How has early atmosphere changed since the early earth? |
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Definition
| Early atmosphere contained water vapors and chemicals released by volcanic eruptions. No oxygen and early photosynthesis did not produce oxygen. Cyanobacteria were the only ones producing oxygen and now atmosphere has lots more of it. Our current atmosphere consists primarily of oxygen (21%) and nitrogen (78%) and is called oxidizing because of chemical reactions produced by oxygen. |
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Definition
| No oxygen present in which an element or ion changes from a higher to a lower oxidation state |
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Term
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Definition
gaseous environment in which an element or ion changes from a lower to a higher positive oxidation state |
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Term
| How was that reducing atmosphere important to building things (combining molecules) on the early earth? |
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Definition
molecules are highly reactive under a reducing atmosphere |
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Term
| What were some of the first problems to be overcome for any life form on earth? |
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Definition
UV light from the lack of ozone in the atmosphere could harm any life
Organisms couldn’t survive on land and needed water for reproduction. |
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Term
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Definition
| ozone is important because it sheilds living things on earth from harmful UV light |
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Term
Where did ozone come from?
Why? |
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Definition
| organisms produced ozone as a result of photosynthesis. |
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Term
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Definition
| Panspermia is the hypothesis that "seeds" of life exist already in the Universe, that life on Earth may have originated through these "seeds", and that they may deliver or have delivered life to other habitable bodies. |
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Definition
| One major problem I remember him talking about was living out of water. Organisms couldn’t survive on land and needed water for reproduction. |
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Term
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Definition
Radioactive dating (half lives)
Position in the sediment layer. Magnetic pole reversions |
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Term
What advantages are mass extinctions?
How common? |
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Definition
Mass extinctions provide advantages for new organisms to evolve. We've had 5. |
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Term
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Definition
| get their energy from other substances (but not carbon) |
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Term
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Definition
| Get their energy from the sunlight and photosynthesis. They also take in co2 as a carbon source. |
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Term
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Definition
| must get their energy from another source. They cannot produce it themselves. |
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Term
| Anerobes are specialized how? |
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Definition
Obligate aerobes: use oxygen for cellular respiration and cannot grow w/o it
Facultative anaerobes: use oxygen if it is presents but can also grow by fermentation in an anaerobic environment
Obligate anaerobes: are poisoned by oxygen |
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Term
| When were anerobes most abundant on earth? |
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Definition
| Before the rise of photosynthetic organisms. (3.5 bya) |
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Term
| How can an organism obtain energy from inorganic molecules like hydrogen sulfide? |
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Definition
| some organisms obtain energy from inorganic molecules by using the electron transport system. |
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Term
| What requirements did the first photosynthetic organisms need to survive? |
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Definition
| They did not produce oxygen, and used methane and hydrogen sulfide. |
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Term
| What about the photosyntetic organisms that evolved later? any special habitats? |
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Definition
| photosynthetic organisms began to grow on the land |
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Term
| Organisms are related phylogenetically: what does that mean exactly? |
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Definition
| It means that they are related by phylum. |
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Term
| Explain primary endosymbiosis. |
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Definition
| Endosymbiosis is the engulfing of a bacterium by another organism which then becomes dependent on the 'eating' organism and they develop a symbiosis. |
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Term
| What was the Cambrian explosion? |
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Definition
| most of the major phyla of animals appear suddenly in the fossil record that was laid down during the first twenty million years of the cambrian period |
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Term
| How could ingestion without digestion take place? |
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Definition
| The smaller organism would be engulfed, but if enzymes did not not dissolve the prey, they could go on living inside the organism. |
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Term
| secondary endosymbiosis is what? |
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Definition
| the engulfing and not digesting of another smaller prokaryotic organism. |
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Term
| What group demonstrates secondary endosymbiosis? |
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Definition
| Chlorplasts in plants are likely the result of secondary endosymbiosis. |
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Term
| How do most antibiotics work? |
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Definition
| antibiotics work by targeting the cell wall on a bacterium that is made up of peptidoglycan |
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Term
| Why are antibiotics most widely over-prescribed? |
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Definition
| because society has begun to see them as a 'quick fix' for any illness |
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Term
| What is the concequence of the overuse of antibiotics? |
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Definition
| Overuse of antibiotics can lead to strains of bacteria that are antibiotic-resistant. |
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Term
| Is feeding antibiotics to livestock really a smart move? |
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Definition
| feeding antibiotics to livestock causes the same concequences as over-prescription of antibiotics to humans. |
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Term
| Why are waste-water treatment plants called 'biological systems'? |
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Definition
| wastewater plants are called biological systems because micro-organisms are used to treat the water. |
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Term
| Why are chemicals we add to our wastewater such a concern for the treatment plants? |
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Definition
| chemicals in wastewater can harm the organisms that are used to help purify the water. |
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Term
| What makes up a prokaryote? |
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Definition
| a nucleoid (DNA), ribosomes, cell membrane, cell wall, and some sort of surface layer, which may or may not be an inherent part of the wall. Structurally, there are three architectural regions: appendages (attachments to the cell surface) in the form of flagella and pili (or fimbriae); a cell envelope consisting of a capsule, cell wall and plasma membrane; and a cytoplasmic region that contains the cell chromosome (DNA) and ribosomes and various sorts of inclusions. |
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Term
| What makes up a eukaryote? |
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Definition
Eukaryote: The Plasma Membrane – the contents of the cell are separated from their surroundings by the plasma membrane, also known as the cell membrane. The plasma membrane consists of protein, lipid and carbohydrate in an arrangement known as the fluid mosaic model. The plasma membrane regulates the transfer of materials between the cell and its surroundings. The Endoplasmic Reticulum and the Ribosomes - within the cytoplasm of most animal cells is a large network of branching channels called the endoplasmic reticulum (ER). On the surface of the ER are a large number of small particles called ribosomes. Ribosomes synthesise the cells’ proteins. Mitochondria – found within the cytoplasm, they are responsible for energy synthesis. The Golgi apparatus – processes, packages and dispatches proteins, within and out of the cell. Lysosomes – found in many cells, these vesicles contain enzymes capable of digesting proteins, nucleic acid, polysaccharide and other materials. Lysosomes are involved amongst other things in the intracellular digestions of particles scavenged by some types of cell during endocytosis. The Nucleus – is a relatively large structure, often found near the centre of the cell. The contents of the nucleus are separated from the cytoplasm by the nuclear envelope. The nucleus contains the genetic components of the cell (chromosomes etc.) Flagella and Cilia – many free living cells (e.g. protozoa), have locomotory flagella or cilia to help them move. Cells within a multicellular animal may also have cilia, for example cells with cilia in the respiratory tract that move mucus in the lungs. The organelles described above may also be found in similar form in many plant cells, as well as these organelles, the constituents of a typical plant eukaryotic cell are as follows: The Cell Wall – is a thick, polysaccharide containing structure that surrounds the plasma membrane in plant cells. The cell wall provides both protection and support. Chloroplasts – the site of photosynthesis within the cell. Vacuoles – larger than in animal cells, they often occupy a major portion of the cell volume. Vacuoles help to expand the plant cell without diluting its cytoplasm, they are also used to store water and cell products. |
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Term
| What is the most significant function that bacteria do for the earth? |
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Definition
| Bacteria are decomposers and also recycle chemicals. |
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Term
| What's the difference between cilia, flagella, and pili? |
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Definition
Cilia are smaller than flagella and both are used for movement, pili are much smaller apendages used for movement and conjugation |
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Term
| Gram-positive vs. Gram-negative means what? |
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Definition
| gram positive means that the outer layer of the cell is mad up mostly of peptidoglycan. Gram-negative bacteria (medically these are usually more harmful) have their peptidoglycan layer sandwiched between other layers. |
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Term
| What are some pathogenic bacteria? |
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Definition
Bacteria that cause E. coli and TB are pathogenic. |
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Term
| What is a bacterial toxin? |
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Definition
| A bacterial toxin is a substance produced by bacteria that is harmful to other organisms. Endospores are toxins that are part of the bacteria, and exospores which secrete toxins |
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Term
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Definition
| The process by which cyanobacteria convert atmospheric nitrogen (n2) to ammonia (nh3) |
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Term
| Why is 'sex' such a big step in evolugion? And why so important that even primitive organisms 'do it'? Think evolution... how does sex help this process? |
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Definition
| sex is a major component of biological diversity. The exchange of genes between organisms; it aids evolution because it creates new combinations. |
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Term
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Definition
| color pigments found in plants among cartenoids and chlorophyll |
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Term
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Definition
| the bluish-green pigment that cyanobacteria use for photosynthesis. |
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Term
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Definition
| The reddish pigment used by cyanobacteria for photosynthesis |
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Term
| What are accessory pigments? |
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Definition
| Accessory pigments are light-absorbing compounds, found in photosynthetic organisms, that work in conjunction with chlorophyll a. |
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Term
| What 2-3 big groups of organisms are noted for the presence of either xanthrophylls (one group) or the phycocyanin's (two groups)? |
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Definition
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Term
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Definition
| Brown algae -- phylum of the kingdom protista consisting of those organisms commonly called brown algae. Many of the world's familiar seaweeds are members of phaeophyta. Like the chrysophytes brown algae derive their color from the presence, in the cell chloroplasts, of several brownish carotenoid pigments, as fucoxathin. With only a few exceptions, brown algae are marine, growing in the colder oceans of the world, many in the tidal zone, where they are subjected to great stress from wave action; others grow in deep water.The books places brown algae in the Stramenopila “clade” along w/ oomycetes, diatoms, and golden algea. |
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Term
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Definition
| red algae -- phylum of the kingdom protista consisting of the photosynthetic organisms commonly known as red algae. Most of the world's seaweeds belong to this group. Although red algae are found in all oceans, they are most common in warm-temperate and tropical climates, where they may occur at greater depths than any other photosynthetic organisms. |
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Term
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Definition
| Green algae -- division of the kingdom of protista consisting of the photosyntetic organism commonly known as green algae. The various species can be unicellular, multi-cellular, coenocytic (having more than one nucleus in a cell), or colonial. |
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Term
Red tides are caused by which protistan group? |
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Definition
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Term
| Which protistan algal group has an external covering of glass or silica? |
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Definition
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Term
The potato blight in ireland was caused by what? |
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Definition
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Term
| Why are Bryophytes considered amphibious plants? |
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Definition
| Bryophytes have flagellates sperm. |
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