Biology 120 Final- Pt 3

Front 1

What are the pros and cons of using the fossil record to determine evolutionary relationships among organisms? What about general pros/cons of using any morphological characteristics?

Back 1

a. Main benefits?
i. Actual physical evidence of organisms that lived in the distant past
ii. Reveals major patterns of descent with modification
b. Three major problems?
i. Gaps in the record
ii. Biased toward larger organisms and “hard parts”
iii. Figuring out age of fossils

Front 2

Define taxonomy, phylogenetic tree, clade, cladogram.

Back 2

a. Taxonomy: ordered division of organisms into categories base on a set of characteristics used to assess similarities and differences
b. Phylogenetic tree: linking classification with phylogeny
c. Clade: places species into groups
d. Cladogram:

Front 3

Primitive vs derived characteristics

Back 3

i. Primitive are shared characteristics whose appearance predates the particular taxon we’re trying to define (example: vertebral column and four limbs). Derived are an evolutionary novelty unique to a particular clade.

Front 4

Homologous vs analogous structures

Back 4

i. Homologous are similarity due to a shared ancestor which can be morphological, genetic or both (ex: arms of mammals). Analogous structures have different lineages but same selection pressure results in similar looking/functioning traits.

Front 5

Define neutral theory, in relationship to the idea of a molecular clock.

Back 5

The “best” genes to look at are the ones that have no overall effect on fitness (general traits needed in different organism that are always passed on)

Front 6

Evidence for reconstructing the history of life on Earth comes from what four sources?

Back 6

Fossil record (physical evidence, patterns of descent with modification), biogeography (study of distribution of species over space and time), comparison of body forms (morphological divergence and convergence), biochemical comparisons (comparison of DNA or protein structure information)

Front 7

What conditions on the early Earth made spontaneous generation of life more likely than currently?

Back 7

Spontaneous generation is when life emerges from non-living material. This doesn’t occur on present day earth but it is possible it arose from four stages of “chemical evolution”
1. Abiotic synthesis of small organic molecules.
2. Joining of monomers into polymers.
3. Packaging of molecules into protobionts
4. Origination of self replicating molecules that make inheritance possible.

Front 8

Define geologic record. What types of events do we use to roughly define major divisions in the record?

Back 8

Geologic record is our current best hypothesis for the history of life on Earth. Typically drawn as a clock (see figure 25.7) to illustrate the eons and divisions.

Front 9

Of the current forms of life on Earth, which do we believe was the first to arise? How long were they the only form of life on Earth? What influence, if any, did this type of life have on the environment of early Earth?

Back 9

Life originated in the ocean 3.5 to 4 billion years ago. Prokaryotes were the dominate life form from 3.5 to 2.0 bya- bacteria and archaea evolved and diverged at this time. (remember stromatolites= layered rocks that form when certain prokaryotes bind thin films of sediment together)

Front 10

explain how mitochondria and chloroplasts might have ended up as complex organelles in eukaryotic cells.

Back 10

Serial endosymbiosis: mitochondria evolved through a sequence of endosymbiotic events where they were later engulfed by larger cells and began living in these larger cells. The same process would’ve occurred for chloroplasts.

Front 11

Briefly explain how multicellular life may have arisen.

Back 11

Similar to the above question. It evolved several times in eukaryotes shown in fossil evidence colonial multicellular organisms. More complex did not arise until the Cambrian explosion.

Front 12

what were the major events in the history of life on Earth, and when did they occur? (hint: think of the clock analogy/diagram shown in class)

Back 12

Major events were the cambrian explosion, mass extinctions, continental drift, and adaptive radiations. These consisted of changes such as atmosphere, climate, ocean, and some, less frequent events, such as catastrophic events (asteroid impacts, for example)

Front 13

Compare/contrast the 5-kingdom and 3-domain systems (i.e. what are the major differences between the two). Why is the Kingdom Protista likely outdated?

Back 13

The 5-kingdom consists of plants, animals, fungi, protista, and monera. The 3-domain system consists of Eukarya, bacteria, archaea.

Front 14

What are the two main ways that solutes can be transported to, from, and within the body?

Back 14

Diffusion of solute within a solution and displacement (movement) of the entire solution to another location.

Front 15

How is the limitation of solute movement by diffusion related to the maximum size of cells? Can multicellular organisms rely on diffusion alone for transport of solutes?

Back 15

Once a given solute enters a cell, diffusion is the primary mechanism by which it moves within the cell. If we were to rely on diffusion alone to transport solutes throughout our bodies, we could not exist.

Front 16

osmoregulation

Back 16

Maintaining salt and water balance.

Front 17

In single celled organisms, what are some examples of organelles that participate in osmoregulation?

Back 17

The plasma membrane is semi-permeable.

Front 18

What organ systems are involved in osmoregulation in larger multicellular organisms?

Back 18

The integument system, excretory, and digestive system.

Front 19

osmotic pressure

Back 19

the hydrostatic pressure necessary to stop net water movement to the glucose side

Front 20

Define iso-, hyper-, and hypo-osmotic solutions. What would happen to a bacteria or other single-celled organism that was placed in each of these solutions?

Back 20

1. Isoosmotic: one that causes no net water movement to or from an adjacent solution. Nothing would happen to a bacteria placed in the solution.
2. Hyperosmotic: one that will draw or gain water from the adjacent solution. The bacteria would shrink/shrivel.
3. Hypoosmotic: one that will lose water to the adjacent solution. The bacteria will swell or even rupture.

Front 21

How do organisms that are osmoconformers differ from osmoregulators?

Back 21

Osmoregulators maintain a specific internal environment irrespective of the outside. Osmoconformers allow your insides to be similar to the outside.

Front 22

What are the 4 major categories of nutritional modes? Can you think of an example of each type that we might have discussed in class so far?

Back 22

1. Photoautotrophs: cyanobacteria, plants, algae.
2. Chemoautotrophs: certain prokaryotes only.
3. Photoheterotrophs- certain prokaryotes only.
4. Chemohetertrophs- many prokaryotes, animals, fungi, protists.

Front 23

Describe the general morphology of the prokaryotes.

Back 23

Consist of Bacteria and Archaea. They can live pretty much anywhere. Earth wouldn’t survive without them.

Front 24

Why are molecular studies so important in understanding the evolutionary relationships among the prokaryotes?

Back 24

Molecular systematic is illuminating prokaryotic phlogeny. Most of our hypotheses are based on this. It’s more precise and can see which are more closely related genetically.

Front 25

What are extremophiles? What types of extremophiles are there, and how might they make a living in these environments?

Back 25

Extremophiles are archaea that can be found in extreme environments. There are methanogens (obligate anerarobes that live in marshes and bogs, producing methane), extreme thermophiles (live in sulfur springs and around deep-sea hydrothermal vents), extreme halophiles (tolerate high saline environments).

Front 26

What are some of the positive and negative ways that humans and prokaryotes interact? Can you think of examples of each?

Back 26

--Positive: research and technology, chemical and pharmaceutical production, bio remediation, food production, etc.
--Negative: cause of ½ all human diseases.

Front 27

be able to describe the major defining characteristics of each group of protists we discussed in class.

Back 27

Extremely diverse, mostly unicellular, most use aerobic respiration, diverse habitats, have both sexual and asexual reproduction.

Front 28

What group of protists do zooxanthellae belong to? What kind of relationship do they have with corals?

Back 28

It’s a dinoflagellate. The relationship with corals is for energy and help make shell while its protected.

Front 29

What is/are the ecological importance of fungi?

Back 29

decomposers

Front 30

Describe the nutritional mode and general morphology of fungi.

Back 30

Feed by absorption from surroundings

Front 31

Define mycorrhizae. What is the importance of this structure?

Back 31

A mutualistic fungus/plant relationship. It increases productivity.

Front 32

What major feature/function is the defining characteristic of each of the five types of fungi?

Back 32

They have radiated into a diverse set of lineages:
1. Chytrids (most primitive)
2. Zygomycetes (variety of life cycles, includes mold)
3. Glomeromycetes
4. Ascomycetes (sac fungi)
5. Basidiomycetes (club fungi)

Front 33

Describe some of the impacts of fungi on ecosystems and human welfare.

Back 33

--They decompose organic material.
--Commercial importance: foods and medical production (ex. Penicillin)
--Symbionts with plants, animals, algae, and cyanobacteria.