We are searching data for your request:
Upon completion, a link will appear to access the found materials.
I can't understand the difference be because both involvery the main cause that is an external stimuli, so how do they differ(
its about the gene that is involved in autonomic movements. while, there is no gene involved in plants for paratonic movements.furthermore, autonomic movements are presents in plants by birth, and paratonic movements are induced in plants by an external stimuli only and not present in plants by birth.
In other words for autonomic movements the plants use an internal cause( simply indicating to gene) and external stimuli both. while, paratonic movemens use external cause only( light, temperature,gravity etc.Hope you understand
Vital movements are those which are exhibited by the living cells or plants or organs and they are always related to the irritability of the protoplasm. These movements are of two types:
A. Movements of locomotion
B. Movements of curvature
A. Movements of locomotion
These movements include the movement of protoplasm inside the cell or movement of whole unicellular or multicellular plant body as in Chlamydomonas, gametes and zoospores.
I. Autonomic movements of locomotion
The movements arising from internal changes or internal stimuli of plant body is called autonomic movements of locomotion. This movement takes place due to the presence of cilia or flagella and movement of cytoplasm (Cyclosis).
Ii. Paratonic or Tactic (induced) movements of locomotion
The movements due to external factors or stimuli like light, temperature and chemicals are called paratonic movement of locomotion (Figure 15.15).
Support and movement are functions of which systems
Living organism shown the responses towards stimuli are called Movement.
Plants require proper strength and support it is necessary to maintain their shape, increase in size and keep them straight and strong. The support maintains balance. In plant body support is provided by two ways.
* Turgidity in soft parts of plants
Support Through Turgor Pressure
The living cell of epidemics, cortex and pith take in water by osmosis. Thus an Internal hydrostatic pressure called “Turgor Pressure”, which keeps them rigid and resistant to bending. If they loose turgidity stem wilts. The turgor pressure is extremely important to maintain the turgidity in plants.
Support Through Supporting Tissue
In plants there are certain tissue called Mechanical
tissues. These tissue provide strength to the plant body.
* Parenchyma is a simple tissue. It is composed of thin walled spherical, oval or elongated cells.
* They are with or without Intercellular spaces.
They are found in cortex, pith and epidemics, mesophyll region of leaves.
Their function is synthesis of food and storage of food. They may serve as a supporting tissue in soft plant due to internal turgor pressure.
* Collencym is a simple permanent tissue. It is composed of rounded, oval or polygonal cells.
* They are living cells with protoplasm.
* Intra cellular spaces are absent and these cells thickened at the corners due to deposition of cellulose and protopectin.
These tissues are found in the dicot stem below the epidermis.
Collenchyma cell provide support to young herbaceous part of the plant. It elongate with the grow stem and leaves.
* Sclerenchyma is a simple permanent tissue. It is composed of long, narrow thick walled cell.
* They have no intracellular spaces.
* They are dead cell without protoplasm.
* A thick materials is deposit along the wall of cell called pectin and lignin.
Sclerenchyma tissues are found in xylem which are vascular tissue.
They provide strength and Mechanical support to the plant parts.
There are two type of sclerenchyma
The sclerenchyma elongated cell with tapered ends. They are tough and strong but flexible Fibers.
The variable often irregular in shape sclerenchyma are called sclereids. Simple unbranched sclerids are generally called stone cell.
An increase in plant girth due to the activity of cambium ring is called secondary growth.
Tissues which are formed by the activity of cambium ring are called secondary tissue.
Significance of Secondary Tissue
The ring of activity dividing cells responsible for lateral growth in plant are called cambium ring.
Secondary growth occurs due to cell division in cambium ring. There are two type
The cambium present between xylem and phloem is called Vascular Cambium Ring. The cell within the vascular bundles are called fusiform initials.
Vascular cambium gives rise to two new tissues.
* Secondary Xylem (Toward the inside)
* Secondary Phloem (Toward the outside)
The secondary Xylem causes most of the increase in stem thickness. Over the year a woody stem get thicker and thicker as it vascular cambium produce layer upon payer of secondary Xylem. These layers are visible as rings.
The outer region of secondary wood is of lighter color and take part in the conduction of water from root to leaf are called Sap Wood.
The inner region of secondary wood is dark brown in color and do not take part in the conduction of water are called Heart Wood.
In most plant heart wood accumulate a variety of chemical such as resins, oil, gum and tannins. Which provide a resistant to decay and insect attack.
The cambium ring present in cortex region and increase the diameter of stem are called cork cambium ring.
Cork cambium cell divide and form new cells on both side.
* Secondary Cortex ——> Inner Side
Cork is formed on the outer side by the cork cambium. Which is an insulating layer prevent transpiration. Cork cell are dead and thick wall.
It is formed on the inner side by cork cambium. It is consist of few layers of parenchymatous cells. They contain chloroplast.
Epidemics, lenticels and cork collectively called bark which is the outer part of stem.
Another important function of the cambium is to form callus or wood tissue on over the wound. The tissue are rapidly formed below the damage surface of stem and root.
Any action taken by living organs to reduce its irritability produce by stimuli are called Movement.
There are two type of movement in plant.
Movement which occurs due to internal stimuli factor inherent inside the plant body itself are called Autonomic or spontaneous movement.
Types of Autonomic Movement
There are three type of autonomic movement.
ii. Growth Curvature Movement
Movement of whole plant body or an organ or material within plant cell from one place to another due to internal stimuli is called movement of locomotion.
* The streaming movement of cytoplasm (Cyclosis).
* Movement of chromosome during cell division.
ii. Growth Curvature Movement
Change in the form and shape of plants or plant organs due to the differences in the ratio of growth of different parts are called growth and curvature movement.
Types of Growth Curvature
There are two type of growth movement.
The growth tip of young stem moves in zigzag manner due to alternate changes in growth on opposite side of the apex. This type of growth is called nutation.
Movement of climber around any rope as found in railway crupper.
When the process of growth occurs in different manner in the parts of a plant and slow in other part it is called Nastic Movement.
There are two type of Nastic movement
When faster growth occurs on the upper side of the organ is known as epinastic.
When faster growth occurs on the lower side of the organ is known as hyponastic.
Movement occur due to change in the turgidity and size of cells as a result of loose or gain of water called Turgo Movement.
* Movement of leaves of touch me not.
The movement occurs due to external stimuli are called paratonic or Induce Movement.
Type of Paratonic Movement
There are two type of paratonic movement.
The non directional movement of parts of plant in response to external stimuli are called Nastic Movement.
Usually this movement occur in leaves or petals of flower.
The nastic movement occurs due to light are called photonastic.
The flower open and close due to light intensity.
The nastic movement occurs due to the touch of any living organism are called Haptonastic.
The movement in response of growth of whole organ toward and away from stimuli are called tropic movement. It is also known as directional movement.
The main type of tropic movement are as follow
The movement of part of plant in response to stimulus of light are called phototropism.
* Positive phototropism in stem
* Negative phototropism in root
The movement of part of plant in response to force of gravity are called Geotropism.
Root display positive Geotropism and shoots negative geotropism.
The movement in response to some chemicals is called Chemotropism.
The hyphase of fungi show chemotropism.
The movement of plant parts in response to stimulus of water is called hydrotropism.
The growth of root toward water is due to positive hydrotropism and shoots negative hydrotropism.
The movement of plant parts in response to stimulus of touch are called Thigmotropism.
The tough hard and rigid framework of the body which gives particular shape and support to animal body are called Skeleton.
Endoskeleton present inside the human body. It consist of 206 bones. In man endoskeleton divide into two parts.
The skeleton composed of skull, sternum, ribs and vertebral column are called Axial Skeleton.
The skull is made up of cranium and facial bones.
The part of the skull consist of eight bones and form a box like structure which protect the brain are called Cranium.
The other bones of skull form face are called facial bones. There are 14 facial bones such as check bones, upper jaws and lower jaws single bone called dentary.
Ribs are semicircular bones attached on their dorsal side with the vertebrae and on their ventral side with sternum.
Rib Cage is composed of 12 pairs of ribs. The lower two pairs of ribs are called floating ribs because they do not attached with the sternum.
The rib cage enclosed the chest cavity and protects heart and lungs.
The narrow rod shaped bones present in ventral wall of thorax are called sternum. It is also known as breast bone.
A hollow spine in which spinal cord protected extend from skull to pelvis are called V column.
(Bones of Vertebral Column)
The vertebral column consists of 33 bones called vertebrate but due to fusion 26 bones are formed.
The skeleton system consist of pectoral girdle and hind limbs and easy to move are called Appendicular skeleton.
Pectoral Girdle and Fore Limb
The girdle present in shoulder region and attach the arm to the trunk are called Pectoral Girdle.
Pectoral girdle consist of two parts.
2. Clavicle ——> Collar bone which connects scapula with sternum.
Arrangement of Bones in Fore Limb
Arm: Humerus forms ball and socker joint with scapular while at distal end humerus forms hinge joint with radius and ulna.
Wrist: The radius and ulna at their distal end from multistage with eight wrist bones called Carpals.
Hand: Five metacarpals from the frame work of palm of the hand.
Digits: Five rows of the phalonges in fingers are attached to the meta carpals. They support the finger.
Pelvic Girdle and Hind Limb
The girdle present in lower region (hip region) and attached the hind limbs (legs) to the vertebral column are called Pelvic gridle.
Structure of Pelvic Girdle
Each pelvic girdle consist of large bone called Innominate. It is formed by the fusion of three bones called Illium, Ischium and Pubis.
The hind limbs consist of
Arrangement of Bones in Fore Limb
Thigh: Femur is the largest bones of the body which forms a ball and socket joint with the Pelvic girdle.
Knee and Calf: At the distal end the femur from knee joint with the proximal end of two parallel bones called tibia and fibula.
Ankle: The distal end of the tibia and fibula form a joint with eight tarsals, which are also attached with five meta tarsal bones of foot.
Digits: Five rows of the fourteen phalonges of the toes are attached with meta tarsals.
The Somatic Nervous System
The somatic nervous system includes everything under your voluntary control as well as one involuntary function, the somatic reflex arc (this is what a doctor tests for when tapping the tendon under your knee with rubber hammer). The SNS includes both afferent (sensory) nerves that transmit various types of information (e.g., smells, pressure and pain) to the the brain for processing and efferent (motor) nerves that direct the muscles under your control, such as those in your legs and arms, to execute certain movements, such as throwing or running.
The nerves of the SNS are classified on the basis of location. For example, there are 12 pairs of cranial nerves, which originate in the head and supply the muscles of the eyes, throat and other areas within the head with both motor and sensory fibers and 31 pairs of spinal nerves, all of which service the voluntary muscles of the trunk, pelvis, arms and legs. The neurotransmitter chemical acetylcholine is an excitatory neurotransmitter in the SNS, meaning that it tends to stimulate movements.
Notes on Paratonic movements of locomotion
These types of movements are also called as tactic movements. The movements occur in response to some unidirectional external stimuli. Depending on the nature of the stimuli like light, temperature, chemicals etc. movements occur here.
(i) Chemotactic movement or chemotaxis – Antherozoids of Bryophytes and pteridophytes move towards the archegonia under the influence of sugars, mucilages and malic acid etc. produced by the disintegration of neck canal cells and ventral canal cells. Such movements are called chemotactic movement.
(ii) Phototactic movement or phototaxism – Some unicellular flagellated algal cells move either towards the source of diffused light (positive phototaxis) or away from the source of bright light (negative phototaxis).
(iii) Thermotactic movement or thermotaxism – many algal species such as Chlamydomonas move from cold water to warm water and from very hot water to water of medium temperature.
Notes on Autonomic movements of locomotion
(i) Ciliary movement – It is the spontaneous movement of plant body from one place to another as seen in certain algal plants like Chlamydomonas, Volvox and their zoospores. They have locomotory organelles called cilia or flagella which help in their movement. (ii) Amoeboid movement – Some slime molds (lower fungi) exhibit this type of movement.
Thier naked mass of protoplasm move by producing pseudopodia like structures. (iii) Cyclosis – It is the streaming movement of protoplasm around the vacuole observed in some plants cells. These are of two types.
(a) Rotation – Here protoplam moves around a single central vacuole in clockwise or anticlockwise direction. Example – In the leaf cells of.Hydrilla, Vallisneria (b) Circulation: The protoplasm moves around different vacuoles in clock wise or anticlockwise direction within a single cell.
It may also occur clockwise manner around some vacuoles and anticlockwise around other vacuoles. Example – Staminal hair cells of Tradescantia.
Plant movements caused by differential growth—Unity or diversity of mechanisms?
A very wide range of plant organ movements have been described and yet it is not clear how each of them is related to the others. This uncertainty has had two undersirable consequences. Firstly, some workers have accepted the idea of a vague unity in the area and have subsequently been misled by information obtained in one system and applied without adequate justification to a study of a quite different system. Secondly, some researchers have evoked a possible diversity to explain why a particular mechanistic explanation may continue to be valid even when the model fails to explain events of a very similar nature in a slightly different system. We argue that this confusion has resulted from a classification of organ movements which has been based on functional rather than on mechanistic considerations. Mechanistic unity is to be expected on evolutionary grounds. This unity, however, may apply only to certain elements of the stimulus-response chain, at certain levels of organization. It follows from this that in seeking this unity, comparisons should be made between equivalent elements of the stimulus-response chain at the same level of organization in different systems. Only when this is done will theories built around the concept of unity provoke meaningful discussion.
Plant Growth and Movements Summary
Growth is one of the most fundamental characteristics of living organisms. It is accompanied by differentiation. The growth cycle of an annual monocarpic angiosperm begins with the zygote which undergoes a period of dormancy. Later, the dormant embryo develops into a seedling which grows into a vegetative phase and ultimately matures into the reproductive phase. The plant finally enters into the senescence stage which leads to death.
Natural plant growth regulators or phytohormones regulate growth and differentiation. These include auxins, gibberellins, cytokinins, ethylene and ABA. Phytohormones act synergistically or antagonistically. Dormancy is overcome by various kinds of influences.
Most viable seeds require the availability of sufficient quantities of water and oxygen and a suitable temperature for their germination. What is crucial for seed germination is the quality of light to which the seeds are exposed last. The light sensitivity is due to the presence of phytochrome, which exists in 2 interconvertible forms Pr and Pfr. Mangrove plants exhibit vivipary.
Flowering is under the control of daily length of light (photo period) and temperature. Depending upon the photoperiodic responses, 3 categories of plants exist namely SDP, LDP, and day neutral plants.
Flowering is a phytochrome-mediated process. The site of perception of light is the green leaf. Plant physiologists have proposed the existence of a flower inducing growth hormone, the florigen, which has not been isolated. The low temperature requirement for flowering is called vernalisation.
Senescence involves a gradual cessation of functional activity and increased cellular breakdown and metabolic failures. Senescence helps maintain plants efficiency and helps in recycling of materials.
Anchored plants show slow movements of their parts. Growth movements are caused due to differentiation or unequal growth of an organ. Some growth movements are autonomic i.e., self controlled e.g., nutations. Others are paratonic such as light, gravity, water or contact. Paratonic movements are further classified into 2 types:
Tropic movements and nastic movements
Turgor movements occur due to the differences in the turgidity or water potential of the groups of cells in different parts of the plant.
Age-related differences in Autonomic/Central Coupling during a Daytime Nap
Age-dependent functional changes are mirrored by declines in both the central nervous system (CNS) and in the autonomic nervous system (ANS) and have been related to pathological aging. Prior studies have demonstrated inter-dependence between central and autonomic events that contribute to cognition. Moreover, our group recently identified a temporal coupling of Autonomic and Central Events (ACEs) during sleep using electrocardiogram (ECG) to measure heart rate and electroencephalography (EEG) to measure sleeping brain rhythms . We showed that heart rate bursts (HRBs) temporally coincided with increased slow wave activity (SWA, 0.5-1Hz) and sigma activity (12-15Hz), followed by parasympathetic surge (RRHF) during non-rapid eye movement (NREM) sleep. Given that there are paralleling age-related declines in both the ANS and CNS, the current study investigated how these declining systems impact ACE coupling during daytime naps in older and younger adults. Despite, lower overall EEG activity during ACE windows in older adults, both younger and older adults showed HRB-modulated increases in SWA and sigma during wake and N2. However, older adults did not show the same pattern during N3. Furthermore, while younger adults demonstrated a RRHF increase only after HRBs, older adults showed an earlier rise and maintenance of the RRHF. Taken together, our results demonstrated that ACE activity remains generally intact with age. Given that age-related deterioration in autonomic and central nervous system activity is implicated in pathological decline, the general maintenance of alignment between the two systems is intriguing and may facilitate novel insights to aging.
Statement of Significance Interactions between the CNS and ANS and have emerged as one of the key markers for health and cognition. Given that both declines in ANS and CNS have been independently implicated with pathological aging and mortality, it’s pressing to understand how the CNS-ANS interactions change with age. Here, we examined the temporal coupling during wake and sleep among young and older adults during a daytime nap. Similar coupling was demonstrated during wake and N2, with older adults showed less coupling in N2 compared to younger adults. Furthermore, older adults showed no coupling during N3. The current study identifying declines CNS-ANS coupling may facilitate novel insights and provide new targets to combat neurodegenerative disease.
Somatic vs Autonomic Nervous System
Despite playing equally important roles for the normal functioning of the peripheral nervous system, there is a huge difference between the somatic and the autonomic nervous system.
Both the somatic and the autonomic nervous systems are essential divisions of the peripheral nervous system. While the former regulates the voluntary movement of the body, the latter is responsible for controlling the body’s involuntary movements, which are also called visceral functions.
A control system that greatly influences the operation of internal organs, the ANS monitors and regulates bodily functions such as respiratory rate, heart rate, urination, digestion, sexual arousal, pupillary response, and digestion.
The SoNS does not affect the body’s internal organs. Instead, it controls movements of the body via the skeletal muscles. It detects and relays sensory stimuli related to vision, smell, taste, pain, noise, touch, and temperature.
The SoNS is comprised of afferent nerves (sensory nerves) and efferent nerves (motor nerves) that stimulate skeletal muscle movement. The ANS, by contrast, consists of a complex network of motor neurons, which control glands, cardiac muscles, and smooth muscles.
The SoNs has two major divisions: the spinal nerves and the cranial nerves. The spinal nerves relay sensory, autonomic, and motor signals from the brain to the body, while the cranial nerves convey sensory information to and from the brain stem.
The ANS, on the other hand, is made up of the sympathetic and the parasympathetic nervous system. The sympathetic nervous system, also known as the “fight or flight” response, prepares the body for situations that trigger fear, excitement, alertness, or intense emotions. The parasympathetic nervous system, on the contrary, is active during rest, relaxation, and digestion.
Number of Neurons
In the ANS, the preganglionic and postganglionic neurons act as a link between the central nervous system and the effector cells, which prompts the body to act in response to a stimulus. Comparatively, in the SoNS, only a single neuron connects the central nervous system and the skeletal muscles.
Lastly, the SoNS releases acetylcholine, a chemical that sends signals in between cells, to the effector cells. Meanwhile, the ANS transmits norepinephrine and acetylcholine to the effector. Norepinephrine is a chemical released by the body in response to stress.