What are Rhabdites and what function do they serve?
the rhabdites are the only, or most common, secretory product released on the ventral locomotor sole and therefore they are thought to form the viscous mucus used in locomotion by ciliary gliding.
What are Rhabdites and their role in planarians?
The rhabdite-containing cell migrates from the mesenchyme to the epidermal surface. Rhabdites are rod-shaped bodies abundant in the epidermis of Turbellaria. These. structures are intensely acidophilic and consist predominantly of protein (13) which. may be combined with a purine component (19).
What are Rhabdites in zoology?
Definition of rhabdite 1 : one of the minute, smooth, rodlike or fusiform structures produced in the cells of the epidermis or in cells sunk within the underlying parenchyma of many turbellarians and a few trematodes and discharged in great numbers in the mucous secretions of these animals.
How many epidermal cells are present in Rhabditis?
There are 120 epidermal cells present in the Rhabditis. Thus, option (a) is the correct answer.
What is common between planaria and Hydra?
Both Planaria and hydra have regeneration capacities. Regeneration is achieved by specialised cells; these cells divide to form a huge number of cells. The mass of cells undergoes modifications to form different types of cells and tissues.
Does Turbellaria have Rhabdites?
Summary. Rhabdites are rod-shaped secretory products characteristic of the Turbellaria but also found in nemerteans, gastrotrichs and annelids.
What is the main function of the epidermis?
Protection. The epidermis acts like armor to protect your body from harm, including ultraviolet (UV) radiation, pathogens (bacteria, viruses, fungi and parasites) and chemicals. Skin color. The epidermis has cells called melanocytes which make melanin, which is a group of pigments in your skin that provides skin color.
What allows hydra to regenerate?
For both reproduction and head regeneration, Hydra vulgaris rely on their head organizer, a cluster of 50 to 100 cells at the apical tip of the head that signals nearby cells to differentiate into either part of the head or the tentacles.
Which type of regeneration occur in hydra?
epimorphosis
This type of regeneration is called epimorphosis and is characteristic of regenerating limbs. The second mechanism is called morphallaxis. Here, regeneration occurs through the repatterning of existing tissues, and there is little new growth. Such regeneration is seen in hydras.
What are the features of Turbellaria?
Major Attributes:
- True bilateral symmetry.
- Dorso-ventral flattening of the body.
- Unsegmented.
- Ciliated epidermis.
- System of sheathed nerve fibers.
- Parenchyma between the epidermis and the gastrodermis.
- Some cephalization.
- Blind ending gut.
What are the six functions of the epidermis?
The skin has six primary functions that help maintain its homeostasis.
- I. Protection. The skin consists of layers, each containing important elements that serve to protect the body against harm.
- II. Heat Regulation.
- III. Secretion.
- V. Sensation.
- VI. Absorption.
Where is melanin produced?
Melanin is produced in melanocytes. These cells are located in different areas of your body, including: Your hair. The innermost layer of your skin.
What type of cell gives our skin color?
melanocytes
Melanin and Your Skin Melanin is made in special cells called melanocytes. These cells are found in the epidermis of your skin. There are at least three ways people can end up with different skin colors.
What type of regeneration is hydra?
B. Members of reptiles such as lizards exhibit autotomy.
What are regenerative cells in hydra?
Hydra is one of the few organisms that possess tremendous regeneration potential, capable of regenerating complete organism from small tissue fragments or even from dissociated cells. This peculiar property has made this genus one of the most invaluable model organisms for understanding the process of regeneration.
How does hydra show regeneration?
Hydra can regenerate missing body parts upon transverse or longitudinal amputation (Fig. 2a). The Hydra polyps are also capable of regenerating from re-aggregated cells. These polyps when dissociated into single cells can reorganize and regenerate into a whole polyp when these cells are pelleted (Fig.
What is Turbellaria with example?
Polycladida
TricladidaPseudoceros bicolor
Turbellaria/Lower classifications
What is the function of the rhabdite?
Rhabdite. They are a defensive mechanism, which dissolve in water, and they are distasteful to most animals who would prey on rhabditid worms. In nemerteans, rhabdites form mucus on which the animals glide.
What is the function of a ribosome?
A ribosome is a complex cellular mechanism used to translate genetic code into chains of amino acids. Long chains of amino acids fold and function as proteins in cells. The function of a ribosome in any cell is to produce proteins.
What are rhabdites in the epidermis?
Rhabdites (from Greek, rhabdos, rod) are rodlike structures in the cells of the epidermis or underlying parenchyma in certain turbellarians, and in the epidermis of nemerteans. They are discharged in mucous secretions.
Are rhabdites excretory or defensive structures?
Some workers have suggested they are defensive structures whose discharge produces a protective, sticky coat around the organism; others consider them to be excretory. Pick a style below, and copy the text for your bibliography. ” rhabdites . ” A Dictionary of Zoology. .