Me
Haagen Dazs (:
"You haven't seen a tree until you've seen its shadow from the sky." — Amelia Earhart

take me to the sky

8:45 am In bio class now. i'll blog whatever i can understand.

Cell dies in 2 ways: Necrosis, Apoptosis.

Necrosis: poisoned, starvation, injury and then die adccidentally. cells will swell up and burst and spill it's guts. often results in inflammation (specific to animal cells). STRESS also makes it that. (i'm gonna get it soon) In necrosis, it is affected by the mast cells. They play a part in allergy response and are located in the dermis layer. When you get an allergy attack, there are substances that contain allergens that cause antibodies that trigger the mast cells that would secrete histamines (chemicals). and the histamines result in the allergy symptoms. (apparently the whole thing is cell signalling)

Introduction of bactieria would cause mast cells to release histamines and cause inflammation. The histamines travel to capillaries and cause all the blood to rush in and dilate and become leaky,to complement proteins to attract phagocytes. (and i just lost her)

Apoptosis: Targetted at certain cells. and it's "programmed cell death". process: cell shrinks alot, then it will become a ball. then blebbing(folding) will occur, and then the remnants are recycled. THE CELLS ARE SO EMO, THEY COMMIT SCUICIDE. She's showing us some video that i don't understand at all. GREAT, i hope all the cells in my body undergo apoptosis NOW! dammit.

cells commit scuicide apparently cause #1, the cell is no longer needed, #2, the longer they live the higher the chances of them having genetic damage.

i need to know the differences between necrosis and apoptosis. DIE. okay, 5 minutes break then we're going to talk about cancer. that's what she said.

CANCER: Uncontrolled cell growth, not enough cell death. tumourous cancer cells have tendency to travel through the bloodstream also called metastatic cells. Deadly ones are malignant tumours, i think that lit teacher in sec 1 told us some of this shit before? (: malignant tumours are irrgular structures. benign ones resemble the parent tissue (is that good? easy to identify?), and they're usually slower compared to malignant, and they are localised versus the malignant one which can spread. for benign tumour, it normally impinges on organ function. benign tumours use BRUTE FORCE (size) to try and screw u up, the other is try and "gain territory".

most cancers are caused by: genetic damage, mutagens, carcinogens. examples of carcinogens: tabacco smoke (the ad that's everywhere), radiation, UV (skin cancer), preservatives, charred/burnt food.

mutations. sometimes, base can change just spontaneously, if it's not repair, then there's a screw up.

TWO HIT HYPOTHESIS:
you are born with 2 normal types of genes, then one screws up, then the other. that takes longer
OR
you are born with one screwed. then the other one screws up. then cancer.

2 sets of genes that play a part in affecting cancer: proto-oncogenes, and tumor suppresor genes. she's focusing on the p53 protein that is mutated in 50% of all cancers whatever that means.

in oncogenes, ther would quote for growth factors, when there is a mutation in the cancer, there is an over production of signals. or the receptor protein ignores all signals. or they just happily signal and divide. OR oncogenes protein leeches onto DNA sequence and refuses to let go, causing a never ending production of the DNA.

in tumor supressor genes, i am confused. They no longer able to repair damaged DNA, or the don't block cell division, or they lose adhesion (???) .

p53: in a normal cell, it triggers enzymes to repair, and trigger the destruction of cells that are damaged beyond repair. in a cancerous cell, they quickly divide and then they don't repair, and screwed up cells are not gotten rid of.

zones to target to tackle cancer: #1 the recognition proteins. #2 enzymes involved in signalling. #3 within the nucleus. #4 cell migration (prevent spreadin). #5 angiogenesis, make sure blood vessels around the cancer cell doesn't keep it alive.

Ways to reduce risks of cancers:

1. Don't smoke
2. Sunblock (JANE!)
3. avoid preservatives
4. don't put your head in front of your microwave
5. eat fruits and vegetables (to have enough fiber in your system, reduces chances of colon cancer)
6. regular screenings
7. don't go binge drinking (causes irreversible damage to liver)

okay, the lesson is ending! (: i apologise for blogging this way but it is a desperate measure to get me to not fail bio!