Lab Exam 2!!!!

Question 1

Protist 3 Groups

Answer 1

Protist 3 Groups

Protozoa: Unicellular heterotrophs, typically animal like

Fungus-like protists (slime molds, water molds) Sometimes referred to as the “lower fungi” because they may be coenocytic (multinucleate), as is one division in the Fungi, during some of their life cycle. They are classified with the heterotroph protists because of their similarities to protozoans.

Algae: Unicellular and multicellular autotroph plant-like organisms

Question 2

Protozoans

Answer 2

Protozoans are unicellular organisms. Most are motile. Protozoans can be found in free-living and parasitic forms and in freshwater or marine environments

Question 3

Phylum: Euglenozoa

Representative: Kinetoplastids

Trypanosoma

Answer 3

Phylum: Euglenozoa

Representative: Kinetoplastids

Trypanosoma

Flagellar movement. A single flagelllum is united basally with the body of cell by an undulating membrane. Amoeboid extensions (pseudo-podia) are also foundi n many flagellates. Trypanosoma gambiense is the causative agent of African sleeping sickness

Slide: blue flagella and ping main part!

Question 4

Phylum: Amoebozoa

Representative: Amoeba proteus

Answer 4

Phylum: Amoebozoa

Representative: Amoeba proteus

Mode of locomotion: Amoeboid movement - pseudopodia. Cytoplasmic extensions change in size.

Method of observation: Living. You can see the organisms on the bottom or side of the culture dish.

Question 5

Phylum: Alveolata

Ciliates

Paramecium

Answer 5

Phylum: Alveolata

Ciliates

Paramecium

Mode of locomotion: Ciliary movement. Cilia have the same itnernal structure as flagella, but are shorter

Question 6

Phylum: Alveolata

Apicomplexans

Plasmodium falciparum smear

Answer 6

Phylum: Alveolata

Apicomplexans

Plasmodium falciparum smear

Mode of locomotion: Nonmotile phases predominate. Blood parasite causing malaria.

Sporozoites are thinner.

Question 7

Radiolaria

Answer 7

Radiolaria

Slender pseudopodia called axopodia (reinforced by microtubules) help the organisms to float and feed.

Question 8

Chert

Answer 8

Chert

A common hard, fine-grained sedimentary rock in the SF Bay Area, composed almost entirely of chalcedony. (an exceedingly fine grained mineral form of quartz). Chert is the ultimate result of the consolidation (under pressure and high temeratures) of accumulations of the siliceous shells of diatoms (autotroph protista with silica shells) and radiolarians (other unicellar protists with shells and spicules (fine needlelike appendages) consisting of silica)

Question 9

What are oomycetes?

Are the oomycetes parasitic or saprophytic?

Answer 9

What are oomycetes?

Are the oomycetes parasitic or saprophytic?

Oomycetes, the “egg fung” (phylum Oomycota), get their name from their sexual reproduction cycle in which large nonmotile eggs are produced inside a special structure called an oogonium. Egg fungi are also called by several common names, including water molds, algae-like fungi, and downy mildews.

Unlike other fungi, with cell walls composed of chitin, the cell walls of oomycetes are made up of cellulose. Another distinction is that the spores formed by oomycetes during asexual reproduction are flagellated, a distinctly protistan character.

Since these molds can attack diseased or dying fish, you may have experienced a problem with ick - disease caused by water molds - in your aquarium. One oomycete genus, Phytophtera, was responsible for the potato famine in Ireland in the 1850s. Today it is responsible for the sudden Oak disease. Another, Plasmopara, almost destroyed the French wine industry.

Oomycetes can be either parasitic or saprophytic.

Saprotroph, a term used for organisms which obtain nutrients from dead organic matter (this term commonly applies to fungi)

Question 10

Water mold slide. Identify antheridia & oogonia

Answer 10

Water mold slide. Identify antheridia & oogonia

Question 11

Water mold zoosporangium

Answer 11

Water mold zoosporangium

Question 12

Pennate and centric Diatoms

Answer 12

Pennate and centric Diatoms

Question 13

Apomorphy

Answer 13

Apomorphy

Any character that the outgroup lacks. An apomorphy is a “derived,” specialized, or advanced character.

Question 14

Principle of parsimony

Answer 14

Principle of parsimony states that the simplest explanation of the data is preferable over more complicated explanations. In cladistics, it is assumed that the cladogram with the fewest steps (evolutionary changes) is probably the most accurate because it suggests the fewer number of evolutionary innovations.

Question 15

Mixed Diatoms

Answer 15

Mixed Diatoms

Question 16

Life Cycle of a cellular slime mold, Dictyostelium

Answer 16

Life Cycle of a cellular slime mold, Dictyostelium

Question 17

Bacillariophyta: Dinoflagellates (Pyrrophyta)

A. Dinoflagellates prepared slide (peridinium)

40X

Answer 17

Bacillariophyta: Dinoflagellates (Pyrrophyta)

A. Dinoflagellates prepared slide (peridinium)

40X

Question 18

Volvox

Answer 18

Volvox. Prepared slide. These are colonies of individual cells resembling Chlamydomonas.

Question 19

Ulva

Answer 19

Ulva

Also called sea lettuce. Ulva is a common marine alga that grows on rocks exposed at low tides. Note the sheet-like photosynthetic blade and the small holdfast.

Oedogonium sexual stages w.m.

Green algae 10X

Question 20

Rhodophyta

What are the products derived from this division?

Answer 20

Rhodophyta (red algae). Note the diversity of blades and pigmentation. Note that some red algae have a protective wall of Calcium carbonate around their cells.

Agar, which is a gelatinous substance obtained from algae, is derived from the division Rhodophyta

>>>Agar and carrageenin are two red algal mucilages that are widely used for gelling and thickening purposes in the food and pharmaceutical industries.

Question 21

Desmid Mixed species w.m. Green algae

Answer 21

Desmid Mixed species w.m. Green algae

40X

Question 22

Several conditions are necessary for natural selection to occur

Answer 22

Several conditions are necessary for natural selection to occur

1. Variability: Individuals within a population must be different from each other
2. Hertability: Some of the variability btwn individuals must have a genetic basis.
3. Differential reproduction: Individuals with some traits will leave more descendants than others.

Question 23

Give two examples of chance events that might affect the course of evolution in nature

Answer 23

In nature, evolution may fluctuate erratically if a natural disaster, such as a flood, wipes out an entire genetic population (such as all white beatles). Also, a disease could randomly infect and kill all deer with bigger antlers.

Question 24

What are the “forces of evolution that cause changes in the allele frequencies in the population?

Answer 24

What are the “forces of evolution that cause changes in the allele frequencies in the population?

These forces include natural seelction (the differential reproduction of phenotypes), gene flow, gneetic drift, immigration and emgration, mutations, and, in some populations, artificial and/or sexual selection

Question 25

p =

q =

Answer 25

p = the frequency of the dominant allele

q = the frequency of the recessive allele

Question 26

In order for HW equilibrium to take place…

In a population at Hardy-Weinber equilibrium…

Answer 26

In order for HW equilibrium to take place…

1. No mutation
2. Random mating
3. population is large
4. immigration and emigration do not occur
5. There is no natural selection

In a population at Hardy-Weinber equilibrium

1. Evolution does not occur
2. Genotypic frequencies can be predicted from allelic frequencies

Question 27

Genotypic frequency

Answer 27

Genotypic frequency is the fraction of the population that is a particular genotype. For example, if a population is 20 percent AA, 20 percent Aa, and 60 percent aa, the gentypic frequencies are .2 AA, .2 Aa, and .6 aa

Question 28

Genetic drift

Genetic bottlenecks vs. founder populations

Answer 28

Drift is exaggerated in small populations such as founder populations. A founder population is a small segment of a population that splinters off from a main population. Often a founder population, because of its small size, has a gene pool that differs from that of the parent stock; the incidence of a rare inherited condition may be greater in the founder group than in the parent group.

“Genetic bottlenecks” occur in the small population of an endangered species. Drift may cause a loss of many alleles and a drastic reduction in genetic diversity. Even if the population recovers in numbers of individuals, its reduced ability to adapt to changing conditions may assure its eventual extinction.

Question 29

If you know allelic frequencies for a population, can you calculate gentypic frequencies? Why or why not?

Answer 29

If you know allelic frequencies for a population, can you calculate gentypic frequencies? Why or why not?

If you know allelic frequencies, you can calculate gentypic frequencies if the population is at HW equilibrium, where the frequency of A = p, and a = , we will always see the following genotypic frequencies:

AA = p^2

Aa = 2pq

aa = q^2

Question 30

Can a population evolve simply due to genetic drift? Explain?

Answer 30

A population can evolve solely due to genetic drift since evolution is simply defined as a change in allelic frequencies, which results from genetic drift.

Question 31

Some lineages changed very little over time. A good example of this would be living fossils like the horseshoe crab or cockroach. Again, discuss the ecological conditions that might result in this sort of long term evolutionary stasis.

Answer 31

Some lineages changed very little over time. A good example of this would be living fossils like the horseshoe crab or cockroach. Again, discuss the ecological conditions that might result in this sort of long term evolutionary stasis.

Some lineages may appear to change very little over time since only their shells and other polymer structures are left behind in the form of fossils. Likewise, their other features/traits (such as colors, mating habits, internal organs, etc.) are not reflected in the fossil record, which indicates that it is possible that these features evolved as well. Furthermore, a long term evolutionary stasis may occur amongst these species if there is little need to adapt since the ecological conditions remain similar, and the current traits are favorable to survival and reproduction.

Question 32

Definition of Naturopathic Medicine

Answer 32

Definition of Naturopathic Medicine

Naturopathic medicine is a distinct primary health care profession, emphasizing prevention, treatment, and optimal

health through the use of therapeutic methods and substances that encourage individuals’ inherent self-healing
process. The practice of naturopathic medicine includes modern and traditional, scientific, and empirical methods.

The following principles are the foundation of naturopathic medical practice:

The Healing Power of Nature (Vis Medicatrix Naturae): Naturopathic medicine recognizes an inherent self-healing process in people that is ordered and intelligent. Naturopathic physicians act to identify and remove obstacles to healing and recovery, and to facilitate and augment this inherent self-healing process.
Identify and Treat the Causes (ToIle Causam): The naturopathic physician seeks to identify and remove the underlying causes of illness rather than to merely eliminate or suppress symptoms.
First Do No Harm (Primum Non Nocere):Naturopathic physicians follow three guidelines to avoid harming the patient:
Utilize methods and medicinal substances which minimize the risk of harmful side effects, using the least force necessary to diagnose and treat;
Avoid when possible the harmful suppression of symptoms; and
Acknowledge, respect, and work with individuals’ self-healing process.
Doctor as Teacher (Docere): Naturopathic physicians educate their patients and encourage self-responsibility for health. They also recognize and employ the therapeutic potential of the doctor-patient relationship.
Treat the Whole Person: Naturopathic physicians treat each patient by taking into account individual physical, mental, emotional, genetic, environmental, social, and other factors. Since total health also includes spiritual health, naturopathic physicians encourage individuals to pursue their personal spiritual development.
Prevention: Naturopathic physicians emphasize the prevention of disease by assessing risk factors, heredity and susceptibility to disease, and by making appropriate interventions in partnership with their patients to prevent illness.
Naturopathic Practice
Naturopathic practice includes the following diagnostic and therapeutic modalities: clinical and laboratory diagnostic testing, nutritional medicine, botanical medicine, naturopathic physical medicine (including naturopathic manipulative therapy), public health measures, hygiene, counseling, minor surgery, homeopathy, acupuncture, prescription medication, intravenous and injection therapy, and naturopathic obstetrics (natural childbirth).

Question 33

vestigial structures

Answer 33

Vestigial structures have lost most if not all of their original funtion through evolution. For example, the appendix in humans is a vestigial structure that previously had digestive functions, much as it does in extant species that hydrolyze cellulose and similar indigestible plant materials using intestinal flora. Meanwhile, the often non-functionminiamlly developed ear muscles are vestigial structures that are remnants of the muscles that humans’ ancestors utilized to better hear potential predators.

Question 34

cladistics

Answer 34

cladistics: an approach to systemeatics in which common ancestry is the primary criterion used to classify organisms.

Question 35

Why are phylogenies useful to scientists?

Answer 35

Why are phylogenies useful to scientists?

Phylogenies, or evolutionary histories of a species or group of species, are useful to scientists since they illustrateevolutionary relationships between organisms. Phylogenies reveal how exactly two species share homologous characteristics because of common ancestry. The evolutionary history of a group of organisms can be represented in a branching diagram called a phylogenetic tree. Also, phylogies are inferred from morphological and molecular data. Phylogenies are quite useful for many applications. Phylogenies are helpful in determining the source sof food sold as whale meat in Japan, and have also been useful in determining the sources of anthrax bacteria through using phylogenetic trees based on DNA data. Phylogenies provide a great deal of information, including the closes living relatives of plants such as maize, which may be useful in genetic engineering.

Question 36

taxonomy

classification

Answer 36

Taxonomy is the study of classfication. Classification, specifically biological classification, is the orderly arrangement of organisms in a hierarchical system that ideally reflects evolutionary history.

Question 37

Life cycle of a Plasmodium

Answer 37

Life cycle of a Plasmodium

The malaria parasite life cycle involves two hosts. There is a sporogonic cycle, exo-erythrocytic cycle, and a erythrocytic cycle.

Question 38

What would you expect if natural selection existed and as different for the two populations in this exercise? For example, what if the black individuals could not reproduce in Pop. A, and the black eyed indivduals could not reproduce in population b?

Answer 38

What would you expect if natural selection existed and as different for the two populations in this exercise? For example, what if the black individuals could not reproduce in Pop. A, and the black eyed indivduals could not reproduce in population b?

If natural selection existed and was different for the two populations in this exercise, the two subpopulations would be more dissimilar in the last generation than the first. If black individuals could not reproduce in population A, there would be no black individuals in the last generation. Likewise, if the blacked indivudals could not reproduce in population B, they would go extinct, and not exist in ensuing generation

Question 39

List two additional examples of convergent evolution and discuss what might have caused these changes

Answer 39

List two additional examples of convergent evolution and discuss what might have caused these changes

Both whales and bats have developed echolocation. Bats developed echolocation to navigate through dark caves, while whales developed echolocation to travel through the murky, dark waters of the ocean. Also, flying fish developed the ability to fly above water in order to avoid predators, whereas birds developed the ability to fly (most likely) after developing wings to caputre small prey and attract mates. Later, these wings were useful in order to migrate, avoid predators, and scavenge for food.

Question 40

autapomorphy

Answer 40

autapomorphy

A character that occurs in only one taxon. Autapomorphies demonstrate the uniqueness of taxa, but they don’t help the cladist identify clades (monophyletic groups).

Question 41

paraphyletic group

Answer 41

paraphyletic group

A paraphyletic group consists of an ancestor and some of its descendants. A paraphyletic group is an incomplete clade, or a grade. It is defined by the absence of at least one character (all group members lack some particular character(s).

Question 42

polyphyletic group

Answer 42

polyphyletic group

A polyphyletic group includes two or more taxa, but not the common ancestor of those taxa. A polyphyletic gropu is defined by at least one similar character that evolved independently (by convergent or parallel evolution) in each group member. Taxa are placed in a polyphyleticc group because they share some superficially similarity, not because they are closely related to one another.

Always ask yourself: Are the taxa put together on the basis of superficial similarity (polyphyletic group) or synapomorphy (monophyletic group)?

Question 43

plasmodial slime molds

Answer 43

plasmodial slime molds

Slime molds are sometimes referred to as the “lower fungi” because they are coenocytic during part of their life cycle. Also, therea re some ways in which slimme molds resemble amoebas. Some slime molds, known as plasmodial slime molds (phylum Myxomycota), are multinucleated masses of streaming protoplasm. Others, the cellular slime molds have bodies, or plasmodia, composed of aggregates of small cells called amoebas. These amoebas retain their identity as individual cells.