Chick report

Ectoderm - serves as outer layer of protection which will become the epidermis, and as a differentiator between other layers, and helps develop the brain and nervous system

Mesoderm - Forms muscles and gonads.

Endoderm - Develops gastrointestinal, reparatory, endocrine, auditory and urinary systems. 

Mitosis Lab

Mitosis/Meiosis Lab

	Field 1	Field 2	Field 3	total cells in phase	fraction of total count	estimated time of stage
Interphase	600	750	800	2150	.96	23hrs 2 min
Prophase	24	20	12	56	.02	28 mins 48 secs
metaphase	8	4	11	23	.01	14 mins 24 secs
anaphase	0	1	2	3	.001	1 min 26 secs
telophase	1	12	3	16	.007	10mins 5 secs
total	633	787	828	2245

The importance of mitosis is that it produces two daughter cells that are each

genetically identical to the original cell. Explain how mitosis accomplishes this.

Include the relevant events that occur in interphase.

-----In metaphase, all genetic information is lined up and copied, so when anaphase begins each new nucleolus gets equal copies of the original genetic information.  

A cell has 32 chromosomes. It divides by mitosis to produce two daughter cells.

How many chromosomes does each daughter cell have? 32

2. Based on your data and pie graph, what do you infer about the relative length of

time an onion root tip spends in each phase of mitosis?

The majority of time is spent in interphase, and all other phases go rather quickly.

3. In Table 3.1, if your counts had included parts of the onion root tip in which cells

were not actively dividing, how might this have changed your results?

Much more of the cells observed would have been in interphase, rather than in any of the other phases.

Using Table 3.2 and reflecting on what you have learned in this lab, list three major

ways that mitosis and meiosis differ.

Meiosis has tetrad linking, Meiosis goes through prophase, metaphase, anaphase, and telophase for a second time, and meiosis occurs during child formation, or within the sexual organs.  

3. How do meiosis I and meiosis II differ?

Meiosis II does not have interphase, Meiosis II is exactly identical to Mitosis, meiosis II is haploid

4. Why is meiosis important for organisms that reproduce sexually?

Meiosis is important for organisms that reproduce sexually because if it wasnt there we would have organisms with too many genes thus creating non-human beings. Meiosis allows the child to have genes of both the parents.

Evolution Notes

Understanding Evolution:

Notes:

Darwin and Wallace described the mechanism for evolution

Darwin developed the idea of natural selection, or survival of the fittest

• Most characteristics of organisms are inherited
• More offspring are produced than are able to survive
• Offspring vary in characteristics

Natural selection can only take place if there is variation. These will be spread through mutations and reproduction

Adaptation is a new trait that helps an organism survive

Divergent evolution is the point of change for two species

Biogeography causes different types of evolution to occur to different organisms

Questions 1-8:

1. c

2. b

3. a

4. d

5. Whichever seeds are capable of growing into plants through the more difficult parts of survival demonstrate natural selection.

6. Because they are similar among completely different species - organisms for that matter

7. A theory means tested multiple times without failure

8. A monkey seems more advanced, because of its human-like characteristics. However, they mouse is just as evolved but in a different way.

Formation of New Species:

A species is a group of individual organisms that interbreed and produce fertile, viable offspring

The closer an organism is in species, the more DNA they will have in common

A hybrid is a cross between two species

Many species can create fertile offspring-hybrids

For species to be made, they need to evolve to the point where they cannot interbreed with any other species successfully 

Allopatric speciation is evolution due to change in location

• Dispersal is a simple movement
• Vicariance is a forced geographical change

Sympatric speciation is evolution in the same location

• Mutation
• Aneuploidity is a change in number of chromosomes
• Polyploid is extra

Reproductive isolation

• Prezygotic barrier
• temporal isolation (breed time)
• Behavioral isolation
• Habitat isolation
• Gametic barrier

Questions 1-8:

1. 2n + 1

2. a

3. b

4. b

5. c

6. c

7. c

8. d

Reconnection and Rates of Speciation:

A hybrid zone is where different species that can interbreed create hybrids

• Reinforcement is when the hybrids move away from each other
• Fusion is when the hybrids become one species
• Stability is when the hybrids continue to be produced

Gradual speciation is when species diverge gradually over time in small steps

Punctuated speciation is when a new species undergoes changes quickly from the parent species

Environment has the most effect on speciation

Questions 3 - 4

3. a

4. c

Population Evolution:

Modern synthesis is how natural selection plays a part in speciation

Microevolution is a change in a population’s genetic structure

Macroevolution is evolutionary changes on a broader scale

Gene pool is the sum of all alleles in a population

Traits

Heredity and Traits Think Quest

1.    Go to the following website: http://learn.genetics.utah.edu/content/begin/traits/

2.    Click on “What is Heredity?”  Summarize what heredity is.

They are the genes from parents that are passed onto their offspring. These genes can be found in the DNA of the first 46 chromosomes we are given. For the child to be healthy, it needs to receive exactly one of each chromosome.

3.    Click on “What is a Trait?”  Summarize what a trait is in your own words.

Traits are notable characteristic of someone, and are passed throughout generations. Physical traits are noticeable, as they deal with appearance, and are inherited. They can also be changed by the environment, like the sun changes hair color. Behavioral traits deal more with instincts, and are most notable in sheepdog, and how well they herd. These traits can be changed, through learning. People can also inherit “disease traits” of their parents. This can be changed, as well, by diet and exercise. Traits that are inherited are either homozygous or heterozygous, which deal with the alleles.  Complex traits are also common, which show a blend of multiple alleles.

4.    Click on “What is a Chromosome?”  Describe the structure of a chromosome.
Chromosomes are made up of DNA, which are wrapped compactly around proteins. Humans have 46, or 23 pairs. This is not the same for all organisms.

5.    Click on “How Do Scientists Read Chromosomes?”  Describe how karyotypes are used.

Size, banding, and centromere position.

6.    Click on “Make A Karyotype.”  Do this activity.  Describe how you knew where to place each chromosome.

Based on their size.

7.    How do scientists predict genetic disorders?

8.    What are telomeres and what is significant about them?

They are the ends of chromosomes, and they help protect them from sticking to each other.

9.    How is genealogy tracked in humans?

Family tree, and telomeres through the blood cells.

10. Look at your own avatar. 

a.     Are the traits you listed for your avatar consistent with what you’ve learned today?  Why or why not? 

b.    Based on what you’ve learned today, do you need to adjust anything about your avatar’s traits or its habitat?  Explain.

c.     Create a genealogy for your avatar going back at least to the grandparents.  Sketch this here or on a separate piece of paper.  Label at least one of the traits on your genealogy.

Hardy Weinberg Lab Report

Hardy Weinberg Lab Report Recessive Allele Survivability AP Biology, Mod 19 Abstract. The theory of recessive allele survivability and its relation to hairless rabbits was examined by using the Hardy Weinberg Model. The survivability of recessive alleles was examined by selecting red and white beads from a bowl to symbolize recessive and dominant alleles - the recessive being white and the dominant being red. The recessive alleles slowly dwindled down to four alleles in the tenth generation, from the original 50, symbolizing the death of the hairless rabbits due to the cold weather. No preference for tree circumference was noted. These data suggest that beaver food choice concurs with the optimal foraging theory. Introduction In this lab, we explore the diminishing presence of recessive alleles, specifically that within hairless rabbits vs. haired rabbits. It is suspected that, through natural selection, the recessive alleles that cause an inhibition on an organism will cause those organisms to die off - making the presence of that recessive alleles less likely to be in the next generation of organisms. In the case of the hairless rabbits, they would die off in the colder months, and the haired rabbits would survive to pass on their genes. The significance of the survivability of recessive alleles is important for the theory of evolution and natural selection. The extinction of millions of different species has aided in the process of evolution for other organisms. Without the disappearing of recessive alleles, it would be very difficult to survive for the organism carrying them. They would have many disadvantages.        The main objective of this lab was to see the process of natural selection taking its course in nature, specifically in hairless rabbits. They make a good example, because they die off more quickly due to the harsh winters of England. This proves that survival of the fittest does take place.        We hypothesized that, through the generations, the hairless rabbits would die off, and the dominant alleled rabbits would soon become the only rabbits to live. We believed this to be true, because - given time - every combination possible will take place, and all of the white rabbits would end up dying. Of course, with only ten generations to work with, some did survive, because not all combinations took place. Methods To show the genes being passed down generation to generation, we used beads to represent the bunnies and the offspring. We used the red beads as ‘F’(dominant) and the white as ‘f’(recessive), we dumped 50 of each into a bowl and picked 2 beads without looking. The two beads we picked out would determine the genes for the offspring. We did this until there were no more beads in the bowl and recorded our results on a table that had 3 columns for each outcome. We would keep the ‘ff’ pairs out of the bowl and repeat the process until we had no more ‘f’ alleles in the bowl, or until we had repeated the lab 10 times (reaching the end of the chart). Eventually, the ‘F’ alleles would be the only beads in the bowl, or the recessive gene would stay in due to chance. Results In the experiment we found, similar to what we predicted, the FF rabbits grew in number, and the ff decreased. Because we were not given infinite amount of time, there were still some ff alleled rabbits that survied: about 2. As shown in the graph, however, there is a clear positive curve for the FF alleled rabbits. The ff alleled rabbits saw a negative curve, which we also predicted. For the Ff alleles, we also saw a negative curve. This makes sense, but we did not predict it in our hypothesis, because it was not an outcome we took into account. Of course, if the white beads would slowly be taken out, then any combination of white beads would diminish - double or alternating between white and red. Discussion The Hardy-weinberg formula allows scientists to determine whether evolution has occurred. Any changes in the gene frequencies in the population over time can be detected. The law essentially states that if no evolution is occurring, then an equilibrium of allele frequencies will remain in effect in each succeeding generation of sexually reproducing individuals. In order for equilibrium to remain in effect, then no mutations, gene flow, or selection can occur. Random mating must occur and the population must be big enough so that no genetic drift can cause the allele frequencies to change. The result of this lab was that as each furless rabbit died off in the previous generation, there would be a decrease in the amount of furless rabbits in the next generation. This is because as the alleles die off, in one generation, it becomes less likely for them to be present in the next generation. Eventually, there will be no more recessive pairs of alleles, as seen in the 10th generation of this lab. The probability of the recessive allele pairs surviving got slimmer through each generation. This lab gave us the opportunity to observe how a specific recessive allele pairs become less likely to appear in an environment that does not suit them. Although some of the hairless rabbits survived through the generations, eventually all the furless rabbits did not survive anymore. Conclusion The purpose of this lab was to learn about the recessive allele survivability  by using red and white beads for hairless rabbit survivability. We now know that the Hardy Weinberg model  allows us to predict the survival rate of hairless rabbits in England. We were able to observe and record survival of the fittest in the lab as the bunnies with the recessive genes couldn’t withstand the environment while the bunnies with two dominant genes or a dominant and recessive continued to live.

Geological Time Scale

3. Take notes on the activity and discuss the geologic time scale as you proceed. Make sure to include explanations for the following (you may include more):

a. Relative dating

Relative order puts events in order from earliest, to most recent.

b. Absolute dating

c. Approximately how old is the Earth?

The Earth is about 4,600,000,000 years old

d. When did life first appear on the Earth?

The first life appeared 3,900,000,000 years ago

e. Law of Superposition

Rock layers are deposited on top of layers that were already there. As more and more layers are deposited, the older rock layers end up at the bottom of the sequence and the newer ones toward the top.

f. Vertical timeline (what does it demonstrate?)

It shows the relative order of events and helps us see connections between events, records are kept to be easily put in order for evidence.

g. Trilobites

Trilobites ("three lobes") are so called because their bodies are divided into three lobes: a middle lobe and one on either side. They first appeared about 540 million years ago.

h. Brachiopods

Brachiopods are marine animals that look a bit like clams. They are still common in cold waters today, but the height of their diversity occurred about 400 million years ago.

i. Radiometric dating

Radiometric dating gives absolute dates using the molecular compositions of the substances surrounding fossils.

j. Eurypterids

The eurypterids were one of the fiercest predators in ancient seas. Some reached more than two meters (six feet) in length, making them the largest arthropods that ever lived. The last ones went extinct about 245 million years ago.

k. Ammonites

Chambered mollusc, similar to today’s mollusc

l. Geologic Time Scale

It represents the entire history of the Earth since its formation, roughly 4.6 billion years ago.The Geologic Time Scale is broken up into several periods of time, during which there were great changes in the biodiversity on Earth.

m. Name the Eons and their major events

-Pre-Archean was before Archean, no evidence supports life during this eon.

-Archean: “original”, this was when the first single-cell organisms began to evolve.

-Proterozoic means "before animal life" which isn’t accurate, but most organisms during this time were simple, this is when algae and worm-like creatures were evolving.

-The Phanerozoic Eon is when complex life started to form on earth. It began with the start of the Cambrian period, 544 million years ago, when most of the major groups of animals first appear in the fossil record, and continues through today.

n. Name the Eras and their major events

Cenozoic: “recent life” Mammals, birds, flowering plants became more abundant during this time.

Mesozoic: Mesozoic means "middle life." Dinosaurs, cycads, and ferns were abundant during the Mesozoic.

Paleozoic: “ancient life” Many animals of today originated then like certain corals and brachipods

o. Name the Periods and their major events

-Cambrian: when most of the major groups of animals first appear in the fossil record.

-Ordovician: known for its diverse marine invertebrates and for the presence of early vertebrates.

Silurian: Coral reefs first started forming and an important time for the evolution of fish

Devonian: The first plants began showing up and growing

Carboniferous: Coal began forming in large deposits, and insects began evolving

Permian: When all of the continents came together to form Pangea, and ended with the largest mass extinction in the history of earth.

Triassic: The animals that survived the mass extinction continued to evolve

Jurassic:  Plant eating dinosaurs dominated the earth. Smaller carnivores ate the larger herbivores.

Cretaceous: Ceratopsian dinosaurs came into existence. Many non-avian dinosaurs became extinct.

Tertiary: Many flowering plants evolved, as well as modern-looking mammals

Quaternary: Mammoths and mastodons, sabre-toothed cats, etc. roamed North America, Asia, and Europe. Most of the world temperate zones were covered by glaciers and uncovered by the warm periods.

p. When did humans come along?

Humans came along in the Quaternary Period along with mammoths, saber tooth tigers, etc.

r. What questions do you still have?