Ecology Class! Dictionary terms. Climate change!

Abrupt Climate Change
Sudden (on the order of decades), large changes in some major component of the climate system, with rapid, widespread effects.

Adaptation
Adjustment or preparation of natural or human systems to a new or changing environment which moderates harm or exploits beneficial opportunities.

Adaptive Capacity
The ability of a system to adjust to climate change (including climate variability and extremes) to moderate potential damages, to take advantage of opportunities, or to cope with the consequences.

Aerosols
Small particles or liquid droplets in the atmosphere that can absorb or reflect sunlight depending on their composition.

Afforestation
Planting of new forests on lands that historically have not contained forests.

Albedo
The amount of solar radiation reflected from an object or surface, often expressed as a percentage.

Alternative Energy
Energy derived from nontraditional sources (e.g., compressed natural gas, solar, hydroelectric, wind). ^[2]

Annex I Countries/Parties
Group of countries included in Annex I (as amended in 1998) to the United Nations Framework Convention on Climate Change, including all the developed countries in the Organization of Economic Co-operation and Development, and economies in transition. By default, the other countries are referred to as Non-Annex I countries. Under Articles 4.2 (a) and 4.2 (b) of the Convention, Annex I countries commit themselves specifically to the aim of returning individually or jointly to their 1990 levels of greenhouse gas emissions by the year 2000. ^[2]

Anthropogenic
Made by people or resulting from human activities. Usually used in the context of emissions that are produced as a result of human activities. ^[3]

Atmosphere
The gaseous envelope surrounding the Earth. The dry atmosphere consists almost entirely of nitrogen (78.1% volume mixing ratio) and oxygen (20.9% volume mixing ratio), together with a number of trace gases, such as argon (0.93% volume mixing ratio), helium, radiatively active greenhouse gases such as carbon dioxide (0.035% volume mixing ratio), and ozone. In addition the atmosphere contains water vapor, whose amount is highly variable but typically 1% volume mixing ratio. The atmosphere also contains clouds and aerosols. ^[1]

Atmospheric Lifetime
Atmospheric lifetime is the average time that a molecule resides in the atmosphere before it is removed by chemical reaction or deposition. This can also be thought of as the time that it takes after the human-caused emission of a gas for the concentrations of that gas in the atmosphere to return to natural levels. Greenhouse gas lifetimes can range from a few years to a few thousand years.

Many more can be seen in this government (EPA) website below by double clicking or typing:

http://epa.gov/climatechange/glossary.html

References:

Environmental Protection Agency website

Developmental Biology! Dictionary. Key definitions words in Gametogenesis!

Acrosome: A bag of enzymes that sits at the tip of a spermatozoan, above the nucleus. It opens during fertilization, releasing enzymes that coat the head of the sperm and break down the various extracellular layers surrounding the egg.

Acrosome reaction: The events in the head of a sperm that opens the acrosomal vesicle, releasing its contents to the outside. The acrosome reaction occurs when the sperm hits the outer extracellular coats surrounding the egg. Components in these coats set off the acrosome reaction.

AMH (anti-Müllerian duct hormone): A hormone produced by Sertoli cells within the testis during mammalian embryonic development. It causes the destruction of the Müllerian ducts, the precursors to the oviducts and uterus.

Anti-Müllerian duct hormone (AMH): A hormone produced by Sertoli cells within the testis during embryonic development. It causes the destruction of the Müllerian ducts, the precursors to the oviducts and uterus.

Corona radiata: In the mammalian ovary, the follicle cells immediately surrounding the oocyte which will remain attached to the egg when it is ovulated.

Corpus albicans: In the mammalian ovary, the scar tissue that replaces a declining corpus luteum.


Corpus luteum: In the mammalian ovary, the follicle that is left after an egg has been ovulated. It functions as an endocrine organ, secreting progesterone and estrogen, which maintain the uterine lining in preparation for implantation.

Cortex: A histological term referring to the outer region of an organ, as opposed to the medulla, which refers to the inner region.


Cortical granules: Vesicles found in the cortical cytoplasm of an unfertilized egg. These contain components which are released to the exterior upon fertilization or activation of the egg. These components modify the extracellular substances such that sperm are no longer able to approach the egg cell surface.

Diploid: Having two of each type of chromosome. 2N is used to indicate the diploid number of chromosomes.  Fibroblast: A cell that secretes extracellular fibers, such as collagen and elastin. It is found in mesenchymal tissues and is the most common cell type of connective tissue.

Flagellum: A long locomotory organelle that extends from the surface of certain cells such as most spermatozoa. It consists of a 9+2 arrangement of microtubules, nine outer doublets and two inner singlets.

Follicle: In a mammalian ovary, the structure that is made up of a developing ovum surrounded by nurse (follicle) cells.

Germ cells: The generic term for cells that are, or will become, gametes (sperm or eggs).



Gonad: The organ in which gametes form. In males, this is the testis, a sperm-forming organ, and in females this is the ovary, an ovum-forming organ. In the embryo, the gonad begins developing in the absence of germ cells, and secondarily becomes populated by the primordial germ cells, the cells that will become the gametes.

Graafian follicle: In a mammalian ovary, a mature, or tertiary follicle.

Haploid: Having only one of each type of chromosome. 1N is used to indicate the haploid number of
chromosomes.

 Hilum: In the mammalian ovary, the narrow region at the proximal end where the ovary attaches to the broad ligament within the body cavity.

Interstitial cells (Leydig cells): In the testis, these are the cells that lie between the seminiferous tubules. They secrete testosterone in response to leutinizing hormone (LH).

Leydig cells: The interstitial cells of the testis. These cells lie between the seminiferous tubules. They secrete testosterone in response to leutinizing hormone (LH) 

Medulla: A term referring to the inner region of an organ, as opposed to the cortex, which refers to the outer region.

Meiosis: The type of cell division that halves the number of chromosomes in cells, taking them from a diploid (2N) to a haploid number (1N) of chromosomes. This occurs only in germ cells. 

 slide or as an insert for the ocular.

Müllerian duct: In the vertebrate embryo, the duct that will become the oviduct and uterus. In
mammals, it also forms the upper end of the vagina.


Oogonium: A developing ovum that is in the gonial stage, dividing by mitosis.


Ootid: A developing ovum in the gonotid stage. An ootid is haploid, with each of its chromosomes
consisting of a single chromatid. The second meiotic division divides the secondary oocyte
asymmetrically, producing one ootid and one tiny polar body.


Ovary: The female gonad in which germ cells form ova.


Polar bodies: The small cells divided off from the developing ovum as it goes through meiosis. Each
meiotic division in the egg is asymmetric, resulting in a large cell that will continue on to become the
mature ovum and a small polar body, that is eventually sloughed.

Polyspermy: Fertilization of an egg with more than one sperm.


Primary follicles: In a mammalian ovary, the follicle as it begins to grow. The follicle cells become
cuboidal and/or columnar and increase in number, forming multiple layers.

Primary gonocyte stage: The stage in germ cell development following the gonial stage. During this stage, the germ cells leave the mitotic stage and enter a stage of growth. At the end of this stage,

the cell enters the first meiotic division.


Primary oocyte: A developing ovum in the primary gonocyte stage, a stage during which the cell is
growing and not dividing. At the end of this stage, the cell enters the first meiotic division. 

Primary spermatocyte: A developing sperm in the primary gonial stage, a stage during which the cell
is growing and not dividing. At the end of this stage, the cell enters the first meiotic division. 

Secondary follicle: In a mammalian ovary, a follicle that has begun to develop an antrum (a space filled with fluid).

Secondary gonocyte stage: The stage in germ cell development following the first meiotic division. The cell at this stage is haploid. Each of its chromosomes consists of two sister chromatids. At the end of this stage, the cell enters the second meiotic division.

Secondary oocyte: A developing ovum in the secondary gonocyte stage. A secondary oocyte is haploid. Each of its chromosomes consists of two sister chromatids. The first meiotic division divides the primary oocyte asymmetrically, producing one secondary oocyte and one tiny polar body. At the end of this stage, the secondary oocyte enters the second meiotic division.

Secondary spermatocyte: A developing sperm in the secondary gonocyte stage. The cell at this stage is haploid. Each of its chromosomes consists of two sister chromatids. The first meiotic division divides the primary spermatocyte symmetrically, producing two secondary spermatocytes. At the end of this stage, the secondary spermatocyte enters the second meiotic division.

Seminiferous tubules: The epithelial tubules within the testis where sperm develop.


Sertoli cells: The nurse cells that support the development of sperm in the mammalian testis. Also,
during mammalian embryonic development, the Sertoli cells secrete AMH (anti-Müllerian duct
hormone), which destroys the Müllerian duct.


Spermatid: A developing sperm in the gonotid stage. The cell at this stage is haploid, with each of
its chromosomes consisting of a single chromatid. The second meiotic division divides the secondary spermatocyte symmetrically, producing two spermatids. At the end of this stage, the spermatid begins the process of spermiogenesis to be come mature spermatozoa.

Spermatogenesis: The entire sequence of events in forming a sperm, from the spermatogonial stage to the mature spermatozoan.

Spermatogonium: A developing sperm in the gonial stage, dividing by mitosis. Spermatozoan: A mature sperm.

Spermiogenesis: spermatozoan.

The differentiation process that transforms a spermatid into a mature 

Testis: The male gonad in which germ cells form sperm.


Theca: Literally, a case. Any sac or casing surrounding an organ or structure. In the mammalian
ovary, it is the layer of cells and connective tissue that surround a follicle.



Theca externa: In the mammalian ovary, the outer portion of the cellular capsule surrounding a
follicle. It is more fibrous than the theca intern. 

Tunica albuginea: Literally, a white cloak. This is a connective tissue sheath found around various organs. Around the testis, it is a tough substantial sheath. Around the ovary, it is thin.

Wolffian duct: In a vertebrate embryo, the duct that first serves the pronephric and then the mesonephric kidney. A synonym for the pronephric and mesonephric duct. In amniotes, it becomes the ductus (vas) deferens, and epididymis.

Zona pellucida: The extracellular coat surrounding a mammalian oocyte. It contains various glycoproteins, ZP1, ZP2, and ZP3, which are important in the fertilization reaction.


Zygote: A fertilized egg following fusion of the egg and sperm. 

References:

http://labs.devbio.com/protected/resources/modules/LabBook/Tyler_LabManual_Complete_2010.pdf

Under Developmental Biology Topic: microRNAs as oncogenes and tumor suppressors.

The above topic was extracted from the 'Department of Environmental Toxicology, The Institute of Environmental and Human Health, Texas Tech University, Lubbock. TX 79409." This is an amazing new development in Biological Science. According to above science article said and I quoted '

"Cancer is one of the most serious diseases in the United States and around the world. There are five major steps for cancer development: initiation, promotion, malignant conversion, progression, and metastasis. Many factors influence the development of cancers: some inhibit tumor development (tumor suppressors), and some promote cancer development (cancer inducers). The formation of cancer is the combined interaction of both tumor suppressors and cancer inducers."
 As we all know that Cancer is one of the fast killing disease in United State and all over the world and many scientific researches and studies were being conducted daily to find an end to the mysterious killing disease, After checking the above topic, I was happy and also willing to share this information to people in my blog and hope it well someone reading it. The brief abstract talks about the important of microRNAs as new class of non-protein-coding, small RNAs, endogenous, which is an important regulatory molecule in animals and plants that regulates the gen expression by translational repression in stage of mRNA cleavega, and mRNA decay by miRNA.

To see how it works, you can click the below website for more information: 

http://www.sciencedirect.com/science/article/pii/S0012160606010967


References:

" microRNAs as oncogenes and tumor suppressors."  By Baohong Zhang, George P. Cobb, Todd A. Anderson.

Clam Cleanup -- Biologists Clam Up Waterways To Determine Sources Of Pollution

Clam Cleanup -- Biologists Clam Up Waterways To Determine Sources Of Pollution

This is amazing things to know about Clam cleaning up! Science has find the new study how to clean water but you know what check this out by double clicking the above website in Developmental Biology new daily. Thanks!
Posted by Akinola Awojope.

Mountain forest study shows vulnerability to climate change

Mountain forest study shows vulnerability to climate change

This is another Ecology blog that will help to know about effect of climate change in mountain forest study. Check out the topic by double clicking it please!
Posted by Akinola Awojope.

NASA Observations Point to 'Dry Ice' Snowfall on Mars

NASA Observations Point to 'Dry Ice' Snowfall on Mars


Science Daily (Sep. 11, 2012) — NASA's Mars Reconnaissance Orbiter data have given scientists the clearest evidence yet of carbon-dioxide snowfalls on Mars. This reveals the only known example of carbon-dioxide snow falling anywhere in our solar system. The above website will link you to the new environmental issues by double clicking it!
The Blog is posted by Akinola Awojope.