lunes

Friday, february 19th 2010

Today´s class topic was SYSTEMATICS.

First, we start with Linnaeus (about the 1700s) who divided nature in three kingdoms: Mineralia, Vegetabilia, and Animalia.

-Mineralia for rocks and minerals.

-Vegetabilia for plants.

-Animalia for animals.

Linnaeus developed the binomial system and named every living organism he knew. The names for the genus species have certain characteristics for being a genus:

- They are written in latin, because is a language that hasn´t change over the years such as Spanish or any other language.

- They must be in written on italics.

- The first letter of the two words must be in CAPITAL letters.

- Description: The genus must include the principal characteristic of the organism.

- Example: Homo Sapiens: man that thinks.

Haeckel (about the 1860s) modified the classification by eliminating Mineralia, since they aren´t living organisms, add another kingdom and renamed the other two. So the 3 kingdoms he put in his theory are:

- Protista: unicellular living organisms.

- Plantae: plants.

- Animalis: animals.

Whittaker (in 1959) proposed 5 kingdoms:

- Plantae: Multi-cell and autotroph*.

- Animalia: Multi-cell and heterotroph**.

- Protista (protozoans): Single cell organisms with a mixed feeding.

- Monera (bacterial): Single cell, heterotroph and prokaryotic, making it the only kingdom that has prokaryotic cells.

- Fungi (mushrooms): Multi and unicell and heterotroph. They have cell wall such as plants which make it eukaryotic but it doesn´t undergo photosynthesis.

*Organisms that produce their own energy.

** Organisms that take their energy from others.

Woese (in 1994) and a group of scientists, before named naturalists, raise the Monera kingdom to a higher level. This proposes 3 domains:

- Archaeobacteria and Eubacteria – instead of the Monera kingdom he created two domains (which is a higher level than a kingdom) and they are prokaryotic .

- The third domain is Eukarya in which are included the Animalia, Plantae, Protista and Fungi kingdoms.

They are many branches arising from one domain. The set of all branches is called Hierarchy of Classification:

Domain-Kingdom- Phylum- Class- Order-Family- Genus- Species

Example:

Stephanie Sotelo

jueves

Monday, November 9th, 2009

This class we saw pictures but this time were of the male reproductive system
And this are the parts of the reproductive system:
-scrotum; the sac of skin that holds the testicles
-testes: the reproductive glands that reproduc sperm
-seminiferous tubules: it creates gametes, namely sperms
-epididymis: tightly coiled tube connecting the efferent ducts from the rear of each testicle to its vas deferences
-vas deferences: is the sperm carryngtube until it reaches the urethra
-seminal vesicle: narrows at the botton and joins the vas deferences, forming the ejaculatory duct
-prepuce: is a piece of skin wich cover paart of the genitals
-prostate: it produces a fluid that carries the sperm out of the body during the ejaculation
-cowpper's gland: produced a secretion that helps lubricate the head of the penis during erection and ejaculation
-corpora cavernosa: two flexible cylinders of erectile tissue
-corpus spogiosum: is a spongy tissue surrounding the urethra within the penis
-penis glans: is the sensitive tip of penis and is communly referred to as the head of the penis
-urethra: travels trough the penis, and carries semen as well as urine
-the testes consist in numerous lobules
http://www.dmacc.edu/Instructors/rbwollaston/Reproductive%20System/Cross_section_of_testicle.gif
Marla Lopez Arechiga

The following links Were provided by Juanita Montoya, you should watch them.

martes

Friday, november 6th, 2009

On this class we talked about female body sexual organs, so heres one of the pictures the teacher explain: http://www.soc.ucsb.edu/sexinfo/images/05-08-femaleinternalside.jpg

We start talking about the outer organs which were:

  • Labia majora, and labia minora
  • Clitoris: is like a heat sensor, it is important on sexual pleasure, it’s also call the “female pennies”.
  • Vagina: is the passage way to the inside organs (connects inner organs with outer organs), it’s made of muscle, and it’s length it’s from 5 to 10 cm.

The outer organs an the vagina works as a filter, and regulates levels of PH, so some bacterias cannot live there, and some bacterias can that’s why there are infections right there, and sperms can live there.

These are some inner organs we spoke about: http://kvhs.nbed.nb.ca/gallant/biology/female_anatomy_frontal.jpg

  • Uterus: this part take care of the product of a pregnant, on this part also happens the process of menstruation.
  • Cervix: connects the vagina with the uterus. This part isn’t flexible as the vagina, so it doesn’t let anything go trough.
  • Fundus: is the upper part of the uterus
  • Ovary: is connected with the uterus, is where female reproductive cells are produce
  • Oviducts: this connect the uterus with the ovary, the ovule travel trough here. Also here starts the process of fecundation
  • Infundibulum: (no it’s not a harry potter spell) the oviducts connect with this part to the ovary. The ovary retains in it’s place also with the suspensory ligament.

We also talked about some structure of the ovary:

http://academic.kellogg.cc.mi.us/herbrandsonc/bio201_McKinley/f28-4a-d_ovary_c.jpg

  • Primary folicus: is the first period of the ovule.
  • The secondary oocyte: is the ovule almost complete
  • Corpus luteum: after the ovary is release it left like an scar, which can be used as a count of how many ovules the ovary has release.

We talked about the menstrual cycle:

http://www.womentowomen.com/menstruation/images/060811_menstrualcycle_w-moon.gif

It’s a process of that occurs each 28 days. If an ovule is release and it’s not fecundated it need to bee throw it out. So when it’s first release from the ovary and then reach the uterus, it attach to the endometrium , this part feed the ovule with proteins and blood, to prepare it to be ready in case of a pregnance, and the endometrium wall start growing of blood, so if the the ovule isn’ fecundated it need to release all that blood and inside of that blood goes the ovule, here’s when the menstrual process occurs, and it hurts because the wall of blood it’s really attached , so it hurts when it’s release.

This are some hormones release during the menstrual cycle:

  • FSH: (follicle stimulant hormone) it cause the ovule.
  • LH: (luthinizant hormone) make the corpus lutheum for ovule.
  • Progesteron: determines how thick is the endometrium.
Eduardo Lopez Ramade

miércoles

Monday October 26th, 2009

reproduction

sexual vs asexual
good bad good bad
recombinatio slow no need 2 cells no variability
survival expensive quick no mutation
need 2 cells easy
rostore apolation

Sexual reproduction need haploid cells and a crossing over.
Crossing over is needed for variability of gens


We saw some videos were they explain the types of sexual and asexual reproduction

Types of sexual reprodduction
internal
external

Types of asexual reproduction
Binary fission
iw a division in two parts wich each have the potential to grow to the size of the original cell


Budding
the two resulting cells are not equal size


Fragmentation or Clonal Fragmentation
(reproduction or cloning) a organism is split into fragments. Each fragment develop into mature ,
fully grown individuals that are a clone of the original organism.
the mothers cells are very important in this reproduction.


Spores genesis
the type of reproduction that the fungi family use. Is by spores; the spores go out of the mashroom (in this case).
It can be male or female spores and mashrooms; and then this mashrooms trough female or male spores. This
female or male spores need the opposite spore to build a diploid mashroom.


Regeneration
is said to regenerate a lost or damaged part if the part regrows so the original function is restored.


Partenogenesis
this is ffound in female where growth and development of embryos occurs with out fertilization by a male.


Hermaphrodistism
is only in animals and plants; they have both male and female reproductive organs, only one works correctly.

Intersex
is only in humans; they have both male and female reproductive organs, only one works correctly.

Marla Lopez

jueves

Monday October 19th, 2009

So this Monday 19th of October =)... We keep watching a little of mitosis, but also we started with meiosis. so this is :

Here is a video of the 4 Steps of mitosis: http://www.youtube.com/watch?v=2WwIKdyBN_s

1. Prophase: the DNA condense to cromosomes
2. Metaphase: the Cromosomes get in the spindles
3. Anaphase: while the cromosomes are on the spindle... they separate to both poles
4. Telophase: the cell divides into 2

Here is other video in which there are many cells doing mitosis in real time =O: http://www.youtube.com/watch?v=m73i1Zk8EA0

So here are some specification about mitosis:

-It happens in EVERY cell EXCEPT on sperm and ovum/ova
-The mitosis happens for reproduction
-It happens all the time... but mostly at GROWTH


These are the similarities between the mitosis and meiosis:


MITOSIS V.S. MEIOSIS
- Division -Division
- mother/daughter - mother/daughter
-all cells except Sexual cells - ONLY sexual cells
- 2 daughters (46 cromosomes) - 4 daughters (23 cromosomes)
- Diploid (genetic info.) -Haploid (genetic info)


Heres a video

http://www.johnkyrk.com/meiosis.html


Juan Pablo Campos

(Liga del ultimo video enviada por Fernando Lopez)

lunes

miércoles

Monday October 5th, 2009

Today we talked about the functions of the ribosomes.
Ribosomes are organelles of the cell that are in charge of a process called Translation.


DNA|RNA
A |A
T |U
C |C
G |G

There is a process in which some enzymes make a copy of DNA but is called RNA.
As you can see in the table above, RNA does not have the letter T, so it is the only change that occurs (T becomes U).

In DNA the letters in one strand will always be connected to another certain letter on the other strand:

A will always be with T & C will always be with G.

Example of a possible DNA structure:
C----G
G----C
C----G
T----A
A----T
T----A
G----C
A----T
C----G
C----G
G----C
A----T

RNA is a copy of only 1 strand (and replacing all T's with U's). So the copy of the DNA example would be:
DNA| RNA
G | G
C | C
G | G
A | A
T | U
A | A
C | C
T | U
G | G
G | G
C | C
T | U

Now what a ribosome would do with this RNA is divide it into groups of 3 letters:
GCGAUACUGGCU=
GCG - AUA - CUG - GCU

Now each group of three letters is called a codon.
Each codon is an Aminoacid, and has a name (the name of each codon is not important for us to memorize, the teacher
will give us a table with the names).
The names of the codons from the example would be:
GCG: alanina
AUA: soleucina
CUG: leucina
GCU: alanina

Now that each part of the RNA is a codon (group of aminoacids) it is a protein that can be used.

BRIEFLY:
RNA: copy of ONE strand of the DNA, but instead of T's has U's.
Ribosomes: converts the RNA into aminoacid chains that conform a protein (Translation).
DNA: has two strands (chains of letters), but only one will be used for the RNA copy.
Proteins: chains of aminoacids
A is to T as G is to C

Luz Garduño

last class we saw how RNA is transform into proteins so basically is a very simple process basically i tell these example and told it to martha and she understand:

imagine that you are in a candy shop and the RNA is the code for example PTP is a pulparindo TTU is a tootsie and BGB is a bubblegum so the RNA is kind of a list with the codes and you are the ribosome's for example in the list you have PTPBGBTTUTTUPTPBGBBGB so what you make is separate the initials in three and get the candies so you got basically a nice basket with a pulpariando then a bubblegum, tootsie,pulparindo,bubblegum,bubblegum, and that kind of linear basket is the protein.

AMINOACID:what makes up a three letter codons

CODON: a 3 letter group like a worg PTP

PROTEIN:a chain of codons

but so these posible can be possible you need kind of to"codify" those messages by finding theryre complementary letter here are the complementary letters for ATCG

A=T

T=A

C=G

G=C

But cause DNA does not has T its change into a U

Naneth Lopez Argil

The RNA copies the DNA Information. It gets to the Rough. E.R. (where the Ribosomes are) and the ribosomes, by the Translation Method, Translate the RNA and make it a Protein. Here is a more detail explanation http://nobelprize.org/educational_games/medicine/dna/index.html


A segment of RNA its at least one protein... those big chains of DNA that RNA copies... it know where to stop copying because of the Determination codes... are to determine where a chain ends. =)

http://nobelprize.org/educational_games/medicine/dna/b/replication/index.html
http://nobelprize.org/educational_games/medicine/dna/b/replication/replication.html

these are more info. of the Replicacion of DNA

And here is info of the genetic codes
http://nobelprize.org/educational_games/medicine/gene-code/about.html


Here is a video of RNA... its cool =) and understandable
http://www.youtube.com/watch?v=Ml0OqAUzEXU

Juan Pablo Campos