Assalamualaikum and hello :)
There have been 7 weeks since I start
learning Biology and Cell Developmental with Dr Parameswari. This week going to
be the last week Dr Parameswari teaching
us this subject and Dr Nik will replace her. For this week, we discussed the test 1 answers and we learn
about plant hormones. Plant hormones are chemicals produced by plants that
alter growth patterns and/or maintenance of the plant.
There are many types of plant hormones.
But we focussed on 5 main hormones in plants. There are Auxins, Cytokinins, Gibberellins,
Abscisic Acid and Ethylene. Different hormones affect different plant processes. When we understand how hormones work, it will
allows horticulturists to manipulate plants for specific purposes.
AUXINS : Auxins
produced in the terminal buds suppress the growth of side buds and stimulate
root growth. They also affect cell
elongation (tropism), apical dominance, and fruit drop or retention. Other than
that, Auxin also plays a role in maintaining apical dominance.
GIBBERELLINS
: Gibberellins promote stem elongation. They are not produced in stem tip.
Gibberellic acid was the first of this class of hormone to be discovered.
CYTOKININS :
Cytokinins promote cell division, and influence cell differentiation and aging
of leaves.
ABSCISIC
ACID : Abscisic acid is considered the “stress” hormone. It inhibits the effects of other hormones to
reduce growth during times of plant stress.
ETHYLENE :
Ethylene is a gas produced by ripe fruits. Ethylene is used to ripen crops at
the same time. Sprayed on a field it will cause all fruits to ripen at the same
time so they can be harvested.
Okay. Done. From what I have learnt, not only for this 7
weeks, but since I studied science in primary school, Biology is very interesting
subject. From my view, when we studied about science, we studied about what
have God created a long time ago. The nature, the organs, and the world.
Because we can not stop questioning why. Why the organs like that ? Why the
viroids effect plants ? Why and why and we get a new experiences and knowledge
everytime we find answer for it. It
helps us get a better understanding about the world in its natural processes, it
is the study of how lives evolves, survives and changes through out the times,
it gives knowledge about the interaction of cells with organs and organisms,
environment and ecosystem, it teaches how various organs and system works on
human body in a perfect way and how everything is connected in our body and
many else.
Biology is about the world. It have been a great 7 weeks with you
Dr. Thank you for your sharing about this interesting subject and also your
experiences. Have a blast !
Thankyou !
Posted at 7:00 AM | 0 comments
Assalamualaikum
and hello :)
This week which is week 6, we learnt about
pollination and development of plant embryo.
The main things if I want to pro in this topic is I have to remember the
name of the flower structures. Stamen,
anther, and many else. Not only humans and animals can reproduce, but plants
also the same.
Below are the structure of flower :
One of the main structure is plant’s
reproductive organs. For female, there hava an ovule that consist of a
megasporangium, megaspore, and one or more protective integuments. Megasporangia
produce megaspores that give rise to female gametophytes. For male, there have
an anther consists of microsporangium. Microsporangia produce microspores.
Microspores develop into pollen grains,which contain the male gametophytes.
There
are two types of pollination. First is self-pollination which is occur in the
same flower. While the cross-pollination which is occur in the different
flowers of the same species. Pollination occur when pollen grain transferred from
anther to the stigma.
So, I think, we as a humans have to respect plants *blur* No
I did not mean that you have to bow when you walk in front of the plants. Okay what I mean is, they are living things
same goes to us, so do not pick them as you all wish. Okay the main point is, they are living things
too ! That is what i want to tell you guys actually :/
Thank you !
Posted at 2:00 AM | 0 comments
Assalamualaikum and hello :)
On week 5, we studied about endosymbiotic
theory. Lynn Margulis, the American biologist provided evidence that some
organelles within cell were at one time free living cells themselves.
Endosymbiotic
theory suggests that :
- - Eukaryotes
arose from a symbiotic relationship between various prokaryotes.
- - Heterotrophic
( aerobic ) bacteria became mitochondria.
- - Cyanobacteria
( photosynthetic ) became chloroplasts.
- - Host
cell was a large eukaryotic cell.
Basically, the theory said that eukaryotes
evolved when a primitive respiring bacteria was engulfed by another bacteria. There
are many evidences for endosymbiosis. One of them are mitochondria and chloroplasts
are similar in size and morphology to
bacterial prokaryotic cells, and also divided by binary fission. Other than
that, Mitochondria and chloroplast have their own DNA and their own ribosomes. It
have approximately 7 to 8 evidencies related to the endosymbiotic theory.
Next, we learnt about cell division and
totipotency. I am pretty sure that you all that take science stream during
schools have learnt this chapter ( cell division ). As I enter matriculation
programme, I studied again about this topic. When said about cell division or
cell cycle, the word that crossed through my mind are mitosis, meiosis, G1
phase, G2 phase and also S phase. In prokaryotes, the cell cycle is simple and
may occur as often as 20 minutes. In eukaryotes, cells that divide regularly
will go through the cell cycle in about 24 hours. Cells in multicellular organisms
divide to replace lost or damaged cells, and also allow the organism to grow.
While unicellular organism divide to reproduce.
And in Thursday, we have Test 1 for
chapter 1 and 2. The question is basically about evolution, about the scientist
involved in the evolution theory especially Darwin. Sorry Dr :( I will do
better next test.
Thank you !
Posted at 9:52 AM | 0 comments
Assalamualaikum and hello :)Today I will story about what I have learnt in week 4. Cell theory. There are two type of cell theory which is traditional and modern cell theory.
Traditional Cell Theory
- All living things are composed of cells.
- - The basic unit of structure and function in
living thing are cells.
- - New cells are only produced from existing cells.
-
Modern Cell Theory :
- - Studies of biochemistry and metabolism proves
that energy flow occurs within all cells.
- - Cells contain hereditary information (DNA) that
is passed from one cell to another cell during reproduction.
- - All cells are basically same in chemical
composition in organisms of similar species and same metabolic activities.
-
There are many scientist that knownly have a lot of contribution to
cell theory. In our scl activities, we were assigned to find out about sveral
scientist. Actually, I have
drawn several illustration of their discovery. Below are picture about their contribution,
date of discovery and the illustration. Please do not laugh because Im not good
in drawing or anything related to it (hate it) :(
Just
in case if you all can not see clearly. First is Robert Hooke. Second is Anton
Van Leeuwenhoek. Thirdly is Theordor Schwann and lastly is Rudolf Virchow.
I also learnt about prokaryotic and eukaryotic cells. These are the
sructures and the differences between both of them.
Well if i have tell you about the similarities and differences of prokaryotic and eukaryotic cells, you need to spend all day reading my blog. Okay just kidding. The main thing is both of them are composed of cells, the basic unit of life, with each cell are surrounded by a cell membrane. That is it !
Next, Dr taught about virruses, prions, and viroids. I considered that all human know what virus is. Come on guys :/ It is sure something that can infect human, animals, plants and even the bacteria. And yes they are considered as non-living things. From what I remembered, they are extremely small in size, and we can only see them through advanced electron microscope ( it is expensive yeah ).
What is prions ? Prions is an infectious agent that is composed primarily protein or the simple word is an infection protein. Prion disease ---> Alzheimer's and Parkinson's Diseases. And for your information research shown that ginko biloba can help in Alzheimer's diseases. Not cure completely but only slow down, something like that.
Viroids is small RNA ( naked and unprotected that do not code for any proteins ) that effect plants. But until now, there are no proves that show the effect of eating plants that infected by viroids to the humans. Maybe someday I want to observe and explore more about it.
Thankyou all !
Posted at 1:30 AM | 0 comments
On week 3, we began to learn about the history of life. We studied about the the first cells or more likely what the first thing existed in this world. We know that there are billions or more humans, animals and plants existed in the world we lived. But do you ever curious what it all began with ?
Based on fossil record, the age of earth was approximately 4.9 billion years old while the diversification of life started 3.9 billion years ago. It means 1.1 billion years needed for the chemical and molecule to accumulate and react. And me ? Yes I 19 years old :p Need to learn more, dude !
Origin of life produced from non-organic matter ( chemical evolution ) on a pre-biotic earth. Then the original life evolved into more complex life and we called this process as natural process of random mutations and natural selection. In a chemical evolution, there are 4 requirements have existed which is :
- - Little or no free oxygen
- - Source of energy to form organic molecules
- - Availability of chemical building blocks
- - Sufficient time for the molecules to accumulate and react
Basically this is the origin of life time line :
Not just that, I learn about classification. About kingdom and else. ( actually i have learned in my matriculation but this is quite simple as we only studied about the kingdom )
There are 6 kingdoms which is :
Kingdom Archaebacteria and eubacteria
- unicellular and prokaryotic
Kingdom Protista
-unicellular/multicelluar and eukaryote
-Autotrophic/Heterotrophic
Kingdom Fungi
-Mostly multicellular
-Eukaryote
-Heterotrophs
Kingdom Animalia
-Heterotrophic
-Multicellular
-Eukaryotic
Kingdom Plantae
-Autotrophic
-Multicellular and eukaryotic
Last but not least, classification is very important as it help us to clarify relationships among organisms, remember organisms and their traits, enabale us to communicate clearly the identity of organisms being studied.
I cant wait to learn new chapter; Cell Theory and prokaryotes. See again ! Thank you.
Posted at 12:25 AM | 0 comments
Assalamualaikum and hello :)
On week 2, we were assigned by Dr Parameswari to watch the second video tittled "Selection In Action". It is about comparing the artificial selection of dogs and corn with the natural selection of the stickleback fish.
Well what are natural selection and artificial selection actually ?
Natural selection is a process whereby organisms with better adaptation to their environment tend to survive and produce more offsprings. It simply requires certain conditions. When they occur, natural selection will occur:
- There must be variation within the population of organisms.
- That variation must be heritable.
- There must be differences in reproductive success based on those heritable differences.
Artificial selection is the breeding of plants and animals to produce diserable traits.The only difference between natural selection and artificial selection is whether the difference in reproductive success is driven by naturally occurring processes, or whether the selection is imposed by humans.
Artifial selection involved the human intervention. Why human do that ? There are some reason :
1. Human attempts to control behavior, not as planned, conscious acts to produce tamer, more tractable animals.
2. Due to fishing regulations dictating that only the largest fish may be kept, humans are artificially selecting fish to produce smaller size fish.
3. Humans have been using agriculture and cross pollinating to manipulate the genomes of different plant species, especially wheat, whose chromosomal number increased as agriculture progressed
2. Due to fishing regulations dictating that only the largest fish may be kept, humans are artificially selecting fish to produce smaller size fish.
3. Humans have been using agriculture and cross pollinating to manipulate the genomes of different plant species, especially wheat, whose chromosomal number increased as agriculture progressed
Here are some example of artificial selection :
Thats all from me Thank you :)
Posted at 12:04 AM | 0 comments
Assalamualaikum and hello :)
On my first week of biocell
class, we studied about evolution and Charles Darwin. We have to watch a video
gave by our lecturer, Dr Parameswari tittled ‘Endless Forms Most beautiful’. The
video is about how Darwin came to publish his theory about the evolution in a
book called The Origin of Species. Yes, Charles Darwin, an English naturalist
who studied variation in plants and animals during a five-year voyage around
the world in 19th century. He proposed that all species of live have
evolved over time from comman ancestors through the process he called natural
selection. Well, it is pretty weird if you do not know who Charles Darwin is if
biology is your courses.
 |
| Charles Darwin |
From what I have learnt and
understand, evolution does not occur in the split of seconds. It take a very
very long time; and the evolutionary change comes through the production of
variation in each generation and this evolution help us in understanding and
knowing better the history of life.
There are many evidence that
come along with the Charles Darwin’s theory about evolution. The evidence of
common ancestry among species comes from many sources ; fossils, biogeography,
embryology and anatomy as well. Fossil Giant Ground Sloths, Armadillo (like
‘gigantic guinea pig’), Coral reef formation, volcanic island and many else is
the examples of evidence that Darwin had observed during his explore.
So, with
these enough evidencies, why majority of people questioning about the evolution
now ? Well I do not know either. Maybe it is only about the monkey that evolved and became human. Why ? Maybe it is related to religion or something. Because yeah what on earth that the monkey have related to us ? Why the monkey have to evolve and suddenly for the long long time they become humans ? It did not even logical to us right. But yes it is proven with the evidencies by Darwin. Do not argue about it.( But personally I want to become a real scientist one day and proved Darwin wronged. ( Joked Dr :( )
From my view, I think that people have to
explore more about the world because I believe that many things; new animals,
new plants, new experiences or even new theory we can found if we have an
effort to explore more the world.
Thank you !
Posted at 2:00 AM | 0 comments
