What are the differences between Tropism and Nastic Movement?

What is the difference between motor and sensory neurons?

differences between nervous control and chemical control

Name the part of neuron:

(a) where information is acquired.

(b) through which information travels as fast as electrical impulse.

 notes on control and cordination

Give the differences and similarities betweem coordination in animals and coordination in plants.

What is the difference between reflex action and reflex arc?

Salivation and vomiting are controlled by

What is Reflex Arc? Draw neat diagram of the components in a reflex arc. Why do impulses flow only only in one direction in a reflex arc?

Name the part of brain which controls

What is structural and functional unit of nervous system? Name its any two components?

what is difference b/w tropic and nastic movements in plants ? plzzz ans it fast.

Could anyone explain the meaning of these lines:Transmission of Nerve Impulse The transmission of a nerve impulse along a neuron from one end to the other occurs as a result of electrical changes across the membrane of the neuron. The membrane of an unstimulated neuron is polarized—that is, there is a difference in electrical charge between the outside and inside of the membrane. The inside is negative with respect to the outside. Polarization is established by maintaining an excess of sodium ions (Na+) on the outside and an excess of potassium ions (K+) on the inside. A certain amount of Na+ and K+ is always leaking across the membrane through leakage channels, but Na+/K+ pumps in the membrane actively restore the ions to the appropriate side. The main contribution to the resting membrane potential (a polarized nerve) is the difference in permeability of the resting membrane to potassium ions versus sodium ions. The resting membrane is much more permeable to potassium ions than to sodium ions resulting in slightly more net potassium ion diffusion (from the inside of the neuron to the outside) than sodium ion diffusion (from the outside of the neuron to the inside) causing the slight difference in polarity right along the membrane of the axon.Other ions, such as large, negatively charged proteins and nucleic acids, reside within the cell. It is these large, negatively charged ions that contribute to the overall negative charge on the inside of the cell membrane as compared to the outside. In addition to crossing the membrane through leakage channels, ions may cross through gated channels. Gated channels open in response to neurotransmitters, changes in membrane potential, or other stimuli. The following events characterize the transmission of a nerve impulse: Resting potential. The resting potential describes the unstimulated, polarized state of a neuron (at about 70 millivolts). Graded potential. A graded potential is a change in the resting potential of the plasma membrane in the response to a stimulus. A graded potential occurs when the stimulus causes Na+ or K+ gated channels to open. If Na+ channels open, positive sodium ions enter, and the membrane depolarizes (becomes more positive). If the stimulus opens K+ channels, then positive potassium ions exit across the membrane and the membrane hyperpolarizes (becomes more negative). A graded potential is a local event that does not travel far from its origin. Graded potentials occur in cell bodies and dendrites. Light, heat,15mechanical pressure, and chemicals, such as neurotransmitters, are examples of stimuli that may generate a graded potential (depending upon the neuron). The following four steps describe the initiation of an impulse to the resetting of a neuron to prepare for a second stimulation: 1. Action potential. Unlike a graded potential, an action potential is capable of traveling long distances. If a depolarizing graded potential is sufficiently large, Na+ channels in the trigger zone open. In response, Na+ on the outside of the membrane becomes depolarized (as in a graded potential). If the stimulus is strong enough—that is, if it is above a certain threshold level—additional Na+ gates open, increasing the flow of Na+ even more, causing an action potential, or complete depolarization (from 70 to about +30 millivolts). This in turn stimulates neighboring Na+ gates, farther down the axon, to open. In this manner, the action potential travels down the length of the axon as opened Na+ gates stimulate neighboring Na+ gates to open. The action potential is an all-or-nothing event: When the stimulus fails to produce depolarization that exceeds the threshold value, no action potential results, but when threshold potential is exceeded, complete depolarization occurs. 2. Repolarization. In response to the inflow of Na+, K+ channels open, this time allowing K+ on the inside to rush out of the cell. The movement of K+ out of the cell causes repolarization by restoring the original membrane polarization. Unlike the resting potential, however, in repolarization the K+ are on the outside and the Na+ are on the inside. Soon after the K+ gates open, the Na+ gates close. Hyperpolarization. By the time the K+ channels close, more K+ have moved out of the cell than is actually necessary to establish the original polarized potential. Thus, the membrane becomes hyperpolarized (about 80 millivolts). 3. Refractory period. With the passage of the action potential, the cell membrane is in an unusual state of affairs. The membrane is polarized, but the Na+ and K+ are on the wrong sides of the membrane. During this refractory period, the axon will not respond to a new stimulus. To reestablish the original distribution of these ions, the Na+ and K+ are returned to their resting potential location by Na+/K+ pumps in the cell membrane. Once these ions are completely returned to their resting potential location, the neuron is ready for another stimulus.

name two hormones secreted by pancreas. write ther functions

draw a schematic representation of reflex arc of knee jerking

is there any difference in how sugar and food taste if your nose is blocked? if so, why might this be happening?

Write two differences between response of plants and response of amimals to stimuli.

design an experiment to demonstrate hydrotropism

1.(a) design an experiment to demonstrate positive and negative geotropism.

(b) give reasons for the following -

(1) use of iodised salt is adviced

(2) salivation is considered an involuntary action

(3) the brain is surrounded by fluid.

Write differences between exocrine glands and endocrine glands

define control and co-ordination

How does our body respond when adrenaline is secreted into the blood?

How does phototropism occur in plants?

if we cut our vein or nerve we will die after 5 to 10 mins but if we cut our hand from the elbow or shoulder we don't die. why?

how does the nervous tissue cause action?

 How do muscle cells move?

How is spinal cord and brain protected in the human body???

Tendrils encircles or coils around the object in contact with it.elaborate. pls ,help with this qstion

what is a reflex action? explain briefly its mechanism in humans. three mark question.

In multicellular organisms how the various activities are controlled and coordinated?

What is the role of the brain in reflex action?

What happens at the synapse between two neurons?

what will happen if you happen to step accidently on a nail

What Is Geotropism?(in plants)

The brain is lodged inside the cavity of skull known as :

How does chemical coordination take place in animals?

Why do blood vessels look blue under the skin?

Name two tissues which provide contol and coordination in animals.

Draw the structure of a neuron and explain its function.

what happens at the synapse between two neurons

explain the structure and function of a nephron.

what is the name of the tissue present in the brain

 Give 5 examples of reflex actions.

What is the difference between enzymes and hormones?

1. differentiate between nastic and tropic movement.( 3 points)

2. differentiate between receptors and effectors.(3 points)

plz help...

what is reflex action??? give five examples

Why do the Mimosa pudica plant leaves droop when touched? exlpian

Q6. (a) Gibberellins, cytokinis, and auxin all promote growth. How would you distinguish them from one another?

(b) Home gardeners commonly pinch off the shoot tips of certain plants in order to promote fuller, bushier growth. Explain why removal of shoot tip should promote such growth.

(c) Provide an example of how a single aspect of growth and development may be influenced by several hormones.

Define nerve impulse. Which structure in a neuron helps to conduct a nerve
impulse:
a. Towards the cell body.
b. Away from the cell body.

Is sleeping a voluntary or involuntary action? Explain

define hormone. write four characteristic of hormones in humans.

Which hormone is responsible for the development of moustache and beard in men?

what is reflex arc?how does it works?explain with a diagram.

what is reflex action?explain the mechanism of reflex action with a suitable example.

What are phytohormones ? Name any two phytohormones along with one fucntion of

what is medulla oblongata

 What is the difference between Cerebrum and Cerebellum...??? (in points plz)

Activity to compare taste of sugar and food with open and blocked nostrils.

please give conclutions of this activity.

Which signals will get disrupted in case of spinal cord injury ?

Aututrophs synthesise food for living world.Justify this statement in one sentence only interconnecting autotrophs and heterotrophs.

List the three kinds of blood vessels of human circulatory system and write their

How does electrical impulse in the neuron change into chemical impulse in the synapse?

laugh at me.-_-

Nervous and hormonal system together performs the function of control and coordination in human beings. Justify the statement.

what is the significance of reflex action?

plzz answrr fastt...:/

what are hydrocarbon?write the name and the general formula of (i) saturated hydrocarbons, (ii) unsaturated hydrocarbons, and draw the structure of one hydrocarbons of each type.how can an unsaturateds hydrocarbon be made saturated?

Explain with the help of diagram how reflex action take place?

name the hormone secreted by thyroid gland and state its functions. why is it improtant for us to iodised salt in ourdeit name the disease caused due to deficiency of iodine and mention its symptoms

expand 3F, 4S- gland

define stem elongation?

examples of voluntary and involuntary actions

how can thyroid activity be determined in man?

what is reflex action?explain with examples.