Senin, 28 Februari 2011


Alit Adi Sanjaya

Jika anda wanita dan sedang hamil atau menyusui, sebaiknya hindari kentang goreng dari restoran siap saji, keripik kentang, serta makanan-makanan lain yang mengandung zat kimia akrilimida dalam labelnya. Zat kimia tersebut selama ini sering disebut-sebut sebagai salah satu penyebab penyakit KANKER. Selain itu, laporan hasil penelitian para ahli Instutute of Biochemical and Pharmaceutical Jerman menyebutkan akrilimida juga sangat berbahaya bagi janin serta bayi yang baru lahir karena dapat mengakibatkan kerusakan pada otak.

Sekitar 10 - 50 % akrilimida yang ada dalam darah ibu mengalir ke dalam darah janin melalui plasenta dan 18,8 mikrogram perliter akrilimida dalam air susu ibu masuk ke dalam darah bayi yang baru lahir. Dengan demikian, jika seorang bayi yang baru lahir meminum setengah liter air susu sibu yang mengandung akrilimida dalam sehari, itu sama artinya dengan memasukkan sekitar 10 mikrogram zat tersebut ke dalam darah si bayi. Apakah Anda mau bayi kesayangan anda kemsukan zat pencetus kanker gara-gara anda????

Jadi sebaiknya ibu-ibu hamil dan menyusui sebaiknya membatasi konsumsi akrilimida tidak lebih dari 20 mikrogram perhari (setara dengan sekitar 10 gram keripik kentang).

Tapi bisa diingat bahwa kentang yang direbus atau dipanggang tidak perlu dihindari oleh ibu-ibu hamil atau menyusui. Begitupun dengan kentang yang digoreng dengan minyak panans bersuhu dari 180 derajat celcius tidaklah perlu dikawatirkan. Karena kandungan akrilimida dalam kentang-kentang itu sangat rendah sehingga aman untuk dikonsumsi.

Alangkah lebih bijaksana anda memiliki konsep bahwa "lebih baik mencegah daripada mengobati". Artinya, mulai sekarang anda bisa batasi konsumsi kentang yang mengandung akrilimida....


(Disandur kembali dari buku ensiklopedia hasil penelitian ilmiah terpopuler dan terpenting)
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Alit Adi Sanjaya

Standard Competency:    
 Understanding the relationship between structure and function of plant and animal tissues, and also its application in the science, environment, technology and community context.

Basic Competency:
2.1 Identify the structure of plant tissues and related it with its function, explain the totipotency as the basic of tissue culture.

Indicator :
1.     Draw many kinds of the plant tissues structure
2.     Identify many kinds of the plant tissues based on its form and location
3.     Identify the mayor characteristic of plant tissues
4.     Explain the function many kind of plant tissues

The Plant Tissues

Plant tissue is formed from plant cells that undergo fission, magnification, and differentiation. Base on its ability to split, plant tissue is grouped into, those are meristematic tissue and permanent tissue.
1.      Meristematic tissue
Meristematic tissue is often called embryonic tissue or basic tissue. It is called embryonic tissue because its cells always make fission to multiply their self. Meanwhile it is called basic tissue because after adult, this tissue will form another tissues.
Meristematic tissue has several characteristic those are:
·         Its cells have thin wall
·         Its shape and size of cell are equal
·         Its relatively rich of protoplasm
·         The content of its cell does not contain crystal and food reservation
·         Commonly it has very small cell cavity.

Base on its origin, meristematic tissue is separated into two those are:
a.  Primary meristem
Primary meristem is a meristem that its cells are direct development of embryonic cells so the advance of embryonic vessels. Its example is in stem tip bud and the trip of root. Meristem found in the trip of stem and the trip of root is called also apical meristem. The activity of this meristem cause stem and root grow enlengthen. Growth caused by the activity of primary meristem is called primary growth.
b.   Secondary meristem
Secondary meristem is a meristem that comes from adult tissue that has make differentiation, such as cambium and crock cambium that happens from parenchyma and collenchyma. Cambium in root and stem od dicotyledon plant is found in the bundle of transport vascular (between xylem and pholem) called vascular cambium. Besides there is also cambium found between two bundles of transport vascular called intervascular cambium. The activity of secondary meristem cause plant ‘s body becomes big. Growth caused by the activity of secondary meristem is called secondary growth.

2. Permanen Tissue
Permanent tissue is a tissue that has undergone differentiation. Base on its shape or function, permanent tissue is separated into epidermis tissue, parenchyma tissue, supporter or strengthener tissue, transport tissue, and crock tissue.

a.   Epidermis tissue
This tissue is tissue that is located most outer so cover all of plant body surface. Epidermis tissue can be found in the surface of root, stem, leaf, fruit, and flower. Epidermis tissue has main function to protect tissue inside of it. Another function is to protect of mechanical destruction, keep tissue temperature for not to high, to prevent the excessive vaporization. Epidermis tissue is found in root has function suck water and mineral salts. In several place, epidermis cells of leaf make modification to be leaf cover cells (stomata). Meanwhile stem epidermis of dicotyledon make modification to be lenticel. The characteristic of epidermis tissue are as follows:

·      The shape of its cells is like cuboid, consist of one layer of cell, and commonly it has no chlorophyll
·      Commonly its covered by wax layer of cuticle. The presence of these wax layer and cuticle have relationship with is function to protect tissue inside of it.
·      In several kind of plant epidermis make modification to be scale of hair
·      The outer part of cell wall of root epidermis that still young will grow to form hair that has function to absorb mineral substance.
b. Parenchyma tissue
Parenchyma tissue is frequently called as ground tissues. The parenchyma tissue is form from living cells with varied morphological as well as physiological structures that still can perform all of their living processes. The characteristic of parenchyma tissues are:
·      The cell membranes composing the tissues are thin
·      Parenchyma cells are alive cells, there is a big vacuole which contains alternative food substance
·      Parenchyma cells is generally polygonal
·      The space between cells in it enables the exchange or circulation of any substance or gases
Parenchyma has functions as follows.
a.      As a place for photosynthesis. This is caused by parenchyma which contains chlorophyll (called chlorenchyma), in young leaf and stem.
b.     As a place of storing food alternative, the characteristic is not colorful, is located inside root, tubers, fruits, and stem.
c.    As a place of storing water, foe example in Agave, Aloe.
d.    As a place of storing air. Air parenchyma is called aerenchyma. Aerenchyma has a rather big intracellular space that has air inside
e.    As a means of transportation. The carrier parenchyma is usually gets longer in the same direction as the way of transporting. This tissue enables to get connected to the tissue inside and outside.

c.  Supporting Tissues
   Supporting tissue is also called stereo that functions to strengthen the body parts of                                 plants.  This supporting tissue is divided into collenchyma and sclerenchyma tissue.
a.     Collenchyma tissue
Collenchyma is a homogenous tissue, consisting of one kind of cell, the primary cell wall is thickened by pectin, cellulose, and hemicellulose. Collenchyma has no lignin. One the cell wall, collenchyma experience local thickening, not at the whole cell wall. Generally collenchyma tissue comes from procambium, but there is also which from the basic meristem. Collenchyma tissue has function as a plant lasing, particularly in growing active organs of plants. Collenchyma is usually located in stems, and leaves, located right under epidermis, rarely in root.

b.     Sclerenchyma tissue
Sclerenchyma is located in the organs of plants that no longer grow and develop. This enables the organs to defend in dealing with any stresses and forces without affecting tissue cells, which are weaker, sclerenchyma cells are dead. The cell wall gets thicker and consist of lignin substances.
Sclerenchyma is divided into two: fibre and sclereid.
·           Fibre
The form of fibre is long and pointed, located in xylem, phloem tissue, or other parts. Both in monocotyledon and dicotyledon. Scelernchyma is generally 2 mm in leght.
·            Sclereid
The form of sclereid cell is round and short. The cell wall contains lignin substance (wood substance) so it rigid and solid. The sclereid cell that that is not branched does not have any extreme form, named brick cells. Sclereid is located in the coconut shell, seeds, or solid part of fruit (pear).

   d.  Endodermis tissue
Endodermis consists of cells that partly experience crock substance thickening on the walls, and partly do not, called repeating cells. These repeating cells have function to side water from cortex to stele (central cylinder). The repeating cells are well known as the caparian strip or band.

e.  Transport Tissue
Vascular tissue pays the role in carrying substances to cover the needs of plants. Vascular tissues is divided  into, they are phloem and xylem.
 Xylem (Wood Vessel)
The cells composing xylem tissue are dead cells and have lignin substance on the cell wall. Xylem has functions to transport of water and mineral salts from roots to leaves for photosynthesis. Xylem consist of xylem elements, including trachea, tracheid, xylem fibres, and xylem parenchyma.
Trachea and tracheid belong to cells that are formed due to secondary cell wall development and continue with cytoplasm removal during maturity. When cells function as carrier tissue, they are dead. Tracheid has characteristic; the cells are cylinder and interrelated on each edge. The interrelated edges will change into perforation hole.
Trachea is also related vessel elements. The fibre in trachea is not clear. Trachea has porous intercelluler fibres. The cell is pointed and long. The trachea wall is perforated called pits. Xylem fibres have long and pointed-edge cells. The wall is thick and narrow pits. Xylem or wood parenchyma contains various substance, for example food stock, tannin substance and crystal.

 Phloem (Sieve Vessel)
The main function of phloem is to transport the photosynthesis result from leaves to the all plants body. Similar to xylem, phloem also has phloem elements. The first elements of pholem is sieve tubes, which has cylindrical cells with perforated edges. Contrary to cells composing xylem tissue, the cells composing sieve tube in phloem tissueare still alive during its functioning as the vascular tissue. However, the cells have no nucleus, ribosome, and vaculoe. The companion cells are cylinder and smaler than sieve tube cells. The companoin cells are located side by side the sieve tube cells and interrelated though plasmodemata.
The third phloem element is phloem fibre, which has long and edge-packed cells. Phloem fibre have a thick cell wall and have function as phloem lasing. The fourth phloem element is phloem parenchyma, which primary  cell walls and belongs to alive cell. Phloem parenchyma has little holes called pits.  Phloem parenchyma contains flour substance, resin, and crystal.

         f.  Cork Tissue
Cork is an elastic, homogeneous mass of flattened dead cells with a fatty substance that makes it almost impermeable to water and gases. Cork oak grows in forests and may exceed 30 m (100 ft) in height, although the average is about 9 m (about 30 ft). The young trees are first stripped of their bark when 15 to 20 years old. This cork is coarse, but successive strippings at intervals of about ten years yield a closer-grained product as the trees mature. The useful life of a tree may be more than 150 years.

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Minggu, 27 Februari 2011


Alit Adi Sanjaya

Standard Competency:    
1.     To understand structure and function of cell as the smallest structures capable of basic life processes

Basic Competency:
1.3. To compare mechanism of membrane transport ( diffusion, osmosis, active  transport, endocytosis and exocytosis )
Indicator :
  1. To differentiate mechanism of active and passive transport
  2.  To explain process and give example of endocytosis and exocytosis
  3. To design experiment with another material to gave evidence membrane transport
  4. To make food preservative with membrane transport concept 

Membrane transport
Passive transport
Active transport
Molecule movement concept 
Movement of a substance from a region of greater concentration to a region of lesser concentration.
Movement of a substance from a region of lesser concentration to a region of greater concentration.
Using cell energy
Without use cell energy
Use cell energy
Diffusion and osmosis
Na and K pump, endocytosis and exocytosis

That is substance enter to the cell. The examples are  pinocytosis and phagocytosis
·         Pinocytosis
Something in receptor membrane will adhere so happen dent in membrane. The dent will make sack.  free sack will stay in cytoplasm. This sack referred as  bubble of pinocytosis. bubble of pinocytosis  will dwindle become little bubble become larger ones bubble.
·         Phagocytosis
Phagocytosis represent food particles swallowing process and foreign cells by phagocytes and amoeba. Food or other particles will patch at membrane, last of membrane will form hollowing. Membrane will close and form sack. 


Representing expenditure of vitamin from within cell. The example Secretion of digestive enzyme by digestive glad.

The K+ / Na+ Pump: An Example of Active Transport
Cellular [K+] is low and [Na+] is high - must pump K+ in and pump Na+ out  K+ and Na+ transport require ATP energy  Experimental evidence has shown that this pump will only work if [K+] is high on outside and [Na+] is high on inside.  This pump works independent of concentration gradient The pump is an integral membrane protein 

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Alit Adi Sanjaya

Standard Competency:    
1.     To understand structure and function of cell as the smallest structures capable of basic life processes

Basic Competency:
1.3. To compare mechanism of membrane transport ( diffusion, osmosis, active  transport, endocytosis and exocytosis )
Indicator :
1.    To explain characteristic diffusion and osmosis transport
2.    To draw cell that experience plasmolyzed
3.    To explain plasmolyzed process

Membrane transport

 Passive transport is  the spontaneous movement of a substance from a region of greater concentration to a region of lesser concentration. The difference between the concentration of a substance in two different areas is known as a concentration gradient. The examples are diffusion and osmosis
ü  Diffusion is the flow of energy or matter from a higher concentration to a lower concentration, resulting in a homogeneous distribution. If one end of a rod is heated or electrically charged, the heat or electricity will diffuse from the hot or charged portion to the cool or uncharged portion. Not all substance or molecules can pass through cell membrane by means of diffusion, for example glucose and amino acid. Both can pass through cell membrane by means of bounded or facilitated diffusion. By this way, glucose and amino acids will bind to permease. Permease is a molecule of transporter protein that assists transportation through cell membrane.

ü  Osmosis is the flow of water molecule from hypotonic solution ( high water concentration, low dissolve substance ) to the hypertonic solution (low water concentration, high dissolve substance ) through semipermeable membrane without energy. An example of osmosis is transfer of sugar solution in scaled glass pipe layered with cellophane (as semipermeable membrane) in container filled in with clear water.

ü  Plasmolyzed is liberated of plasm membrane because water in cytoplasm go out. When plant cell in hypertinic condition so a water in cell will go out from cell and make wrinkle cell. 

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Alit Adi Sanjaya

Joint/articulation is a conncetion between two bones or more. Joints cause elbows and knees can fold and rotate. There are three types of joints: diatrhrosis, amphiarthrosis, and synarthrosis.
a.    Diarthrosis
Diarthrosis is a joint that it is possible to move freely. The synonym of diarthrosis is synovial joints. This joint cause many kinds of movement. In this joint bone meet in articular/joint capsule. There is synovial membrane in articular/joint capsule that expect synovial liquid (joint lubricant) that fills joint socket. The function of synovial liquid are to grease joint, feed the cells in joints area, and absorb shock. Synovial liuquid is by sinovial membrane cells. In joints, theree are cartilaginous tisssues taht coat the joint. All diarthrosis joint have synovial socket. Diarthrosis joints consist of hinge joint, gliding joint, pivot joint, saddle joint, ball-and-socket joint, and condyloid joint.
1.    Hinge joint
Hinge joint ios in elbow and knee. In this joint, the end of a bone that is curve joins with another end of a bone that is concave. This joint produce one axial movement looks like in doo-hingeor window-hinge.
2.    Gliding joint
Gliding joint is a connection of flat interskeleton, for example the joint between carpal and metacarpal. This joint produces awkward slidding movement and doesn’t have axis, example forward and backward movement.
3.    Pivot joint
In pivot joint, one bone end twined around (forming rings) the other end. Pivot joint is in joining of atlas bone and axis bone that cause our head can be rotate and shake from side to side.
4.    Saddle joint
In this joint, other bone end looks like saddle and another end is inside of it. For example, metacarpal is a saddle for phalanx. The movement produce are axial and limited.
5.    Ball-and-socket joint
Ball-and-socket  has the characteristic that one bone is hump and it gets in another bone end looks like a bowl. This joint produce free three axial movement. Ball-and-socket joint connect humerus with scapula, and femur with pelvis.
6.    Condyloid joint
The characteristic of condyloid joint is one epiphysis is oval and come inside of another lobed epiphysis. This joint produce two axial movements, example left to right movement, forward to backward, back and front movement. The condyloid movement is in joint between carpal with radius and ulna.

b.    Amphiarthrosis
Amphiarthrosis is a connection of interskeleton that is connected by cartilage so it may create few movement. Types of amphiathrosis joint which is simphysis and syndesmosis.
1.    Simphysis
Its called symphysis if the joint is connected by cartilage. For example vertebrae joint and symphysis pubis
2.    Syndesmosis
Its called syndesmosis if a connection of interjoint that is connected by cartilage and ligamnents. For example the joint between fibula and tibia.

c.    Synarthrosis
Synarthrosis is a joining of interbones that is connected by ligaments that suffers from ossification so it may not create a movement.  The types of this joint that is synchondrosis and synfibrosis.
1.    Synchondrosis
In synchondrosis, the two bone ends are connected by hyaline, for example the joining between ribs bone and vertebrae.
2.    Synfibrosis
In synfibrosis, the two bone end are connected by dense fibrous connective tissue, for example suture.

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