Control of ADH
The concentration of the blood is monitored by osmoreceptors in the hypothalamus.
The higher the concentration of the blood the less water there is in the blood.
If the concentration is too high, impulses are sent to the pituitary gland which then releases more ADH.
The water levels will be brought back to normal and the impulses stop.
Nephrone is the functional unit of kidney!
Take note of the structures found in nephrone !
The following diagrams are useful for you to get the overall picture of what happen during the event.
And the cross section of the skin...the structures which play role in HOMEOSTASIS..please take note !
..Favourite Question in the exam !!
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates.
They are essential in the urinary system and also serve homeostatic functions.
They serve the body as a natural filter of theblood, and remove wastes which are diverted to the urinary bladder.
In producing urine, the kidneys excrete wastes such as urea andammonium;
the kidneys also are responsible for the reabsorption of water, glucose, and amino acids.
The kidneys also produce hormonesincluding calcitriol, renin, and erythropoietin.
Located at the rear of the abdominal cavity ,the kidneys receive blood from the paired renal arteries, and drain into the paired renal veins.
Each kidney excretes urine into a ureter, itself a paired structure that empties into the urinary bladder.
Resting on top of each kidney is an adrenal gland.
Each adult kidney weighs between 125 and 170 grams in males and between 115 and 155 grams in females.
The left kidney is typically slightly larger than the right.
The kidney has a bean-shaped structure, each kidney has concave and convex surfaces.
The kidney is approximately 11–14 cm in length, 6 cm wide and 4 cm thick.
**Courtesy frm Wikipedia.TQ.
Terbaru di pasaran!
2011 product...Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms
The main role of DNA molecules is the long-term storage of information.
DNA is often compared to a set of blueprints, like a recipe or a code, since it contains the instructions needed to construct other components of cells, such as proteins and RNA molecules.
The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in regulating the use of this genetic information.
DNA consists of two long polymers of simple units called nucleotides, with backbones made of sugars and phosphate groups joined by ester bonds.
These two strands run in opposite directions to each other and are therefore anti-parallel.
Attached to each sugar is one of four types of molecules called bases.
It is the sequence of these four bases along the backbone that encodes information. This information is read using the genetic code, which specifies the sequence of the amino acids within proteins.
The code is read by copying stretches of DNA into the related nucleic acid RNA, in a process called transcription.
Within cells, DNA is organized into long structures called chromosomes.
These chromosomes are duplicated before cells divide, in a process called DNA replication.
Eukaryotic organisms (animals, plants, fungi, and protists) store most of their DNA inside the cell nucleus and some of their DNA in organelles, such as mitochondria or chloroplasts.
In contrast, prokaryotes (bacteriaand archaea) store their DNA only in the cytoplasm.
TQ Courtesy from : http://en.wikipedia.org/wiki/DNA
DNA model in Bio Lab
The Form 4 girls are learning about DNA in Chapter 4: Chemical Composition..
I'm using the activity ,which idea was extracted from BioTech symposium attended last year !!
Using 4 different colours of straws to represent 4 different nitrogenous bases...
Girls joined their group DNA to form a longer chain !!
Individual DNA was merged to become a long one!
a nice double helix !!
