Scribepost for 1.27.11

ANNOUNCEMENTS: We have a bio day tomorrow in the auditorium.:D

HOMEWORK: Finish the Natural Selection Lab (page 17 in the Unit Packet)

RECAP: For the whole class period we worked on a lab about Natural Selection

BACKGROUND INFO:

Natural Selection- The process by which organisms with variations most suited to their local environment survive and leave more offspring.
Basically, only certain individuals in a population produce new individuals, like in artifical selection. Natural selection occurs in any situation in which more individuals are born than can survive (the struggle for existence), there is a natural heritable variation (variation and adaptation), and there is a variable fitness among individuals (survival of the fittest).

LAB: First, we took one of the fabrics and laid it down on our table. Taking ten differently colored pieces of paper, we cut out ten holes from each of them (thats a hundred in total) and laid them randomly around the cloth. We chose two predators who randomly took the first paper chips that they saw until they reached forty. Taking eighty in total, there was supposed to be twenty left on the cloth. We recorded the number of chips there were by color on our data table. Then, we multiplied those numbers by five, which is supposed to represent the organisms reproducing. We then punched the holes needed to reach the number. For example, say that there were five yellow chips left on the cloth. Five times five is twenty-five, so the yellow chips have now grown to that number. But since you already have five chips you only need to punch out twenty more. After doing that for all the colors, we recorded our data, and repeated all of these steps for the second and third generation.

EXPLANATION: So, what did this lab have to do with Natural Selection? As explained before natural selection consists of four other parts, the struggle for existence, variation, adaptation, and survival of the fittest. The stuggle for existence is literally what it means: an individual stuggling to survive and obtain the necessities of life, and competing with others for it. In the lab, we were the predators and the paper chips were the ones struggling to survive. Variation and adaptation both mean what an individual has that helps him to survive, whether it be a trait or a stratedgy.
Adaptation-Any heritable characteristic that increases an organism's ability to survive and reproduce in its envoirnment
For this lab, the adaptation some chips had were camoflauge. Certain colors blended in with the cloth, so when the 'predators' were randomly picking chips, it would've been hard to notice one the same color as the background. A good adaptation means a high fitness level.
Fitness-how well an organism can survive and reproduce in its envoirnment
People with adaptation that were not well suited to their enviornment, like the chips that stood out, had a low fitness level. The difference in rates of survival and reproduction is called the survival of the fittest. The ones that survive are meant to then reproduce and pass adaptation on to the next generation.

The next scriber is.................Carly(=

1.25-26.11 Scribe

11.25&26.11 Scribe

Homework: read 16.2 and only take notes on 16.3 due Thurs.
& complete graph for Beak lab due Thurs.

Announcements: Tv ad project groups no more than 4 in a group and this will be due sometimenext unit. this lab can be found on page 2 in your unit packet
Also, from now all assignments and homework will be posted on moodle, be sure to look on the google calender on STS Bio home page


Recap from 1.25.11
~ Today Mr.Paek discussed new semester requirements, and calenders where to look up homework besides the scribe posts, we also began our new unit of Evolution, we recieved our new unit packets and assignment sheets. we went over a "long-term" project the info-mercial or tv ad about Endangered Species.
Then we took notes and discussed the impelling and dubious topic of Lamark's theory in distinction to Darwin's theory. that took up most of class in the remaining 10 minutes we watched a video about Darwins discoveries and destinations.


Lamark's Theory:

Desire to change- animals changed in structure b/c they have a desire to improve
(example used: suppose if there was a short neck girraffe and it could not reach the leaves its desire would want to have a longer neck, which in the next generation the necks would be longer)
Use And Disuse: use it or lose it- if a body part or structure is not being used it would be lost or disappear in later generations.
Acquired characteristics were inherited- any changes in adult were passed on to the offspring ( example: if a parent is good at puzzles, child will automatically be adequate to puzzles.) ( another example: Mr.Paek explained if he got his son to bulk up have muscles then b/c of Lamarks theory then Mr.Paeks grandchild would have characteristics of bulked up muscles)


Darwin's Theory:

Overproduction of offspring- organisms tend to produce more offspring then needed to replace # of past generation population
Struggle for Existence- competiton for predatation, and resources always present
Variations in Population Exist- difference in structureexist at birth not acquired
- these traits are inheireted from parents
Fitness- physical traits and behaviors to survive and reproduce
Common Descent- different species share common ancestors

Natural Selection:
Definition: organisms best suited for their enviroment conditions to survive, and reproduce they will pass on their characteristics to their offspring "survial for the fittest-not necessairly the strongest or fastest"
Conditions that help - mutation - source of variation in genes
Gene flow- genes move between population
Adaptions- traits that survive from one generation to the next
Examples- peppered moth durin industrial revolution in england, two phentoypes for moths black/speckled, when the bark of the trees got discolored the population changed mostly speckled to black . ( we were shown visuals in class)

1.26.11

Today in class we did a lab which took pretty much the whole class period. this lab was about natural selection and adaptation.

we were put into groups and were to move around the room to 5 station where there different types of meals for birds.

we were given for "beaks" forceps,pliers,spoon, and staple remover these were to repersent the different sorts of beaks and how they adapt to the enviroment they are in and the food that is available.

At the five stations each had either rice, staples, rubber bands, foam, or sunflower seeds. our job was to pick out as many of the foods as we can with the "beaks" we were given this was to show which beak adapts well and will be the fittest in these enviroment and which won't. then we had to record our data and graph, and fil out analysis questions this lab is available on pages 4-8. Dont forget if you were unable to complete your graph in class it is homework.

I

really dont know who to pick for scriber, because I don't want to be unfair so who ever volenteers can be scriber. =]

1.25-26.11 Scribe