CHAPTER 6 Control and Coordination KSEEB SSLC CLASS 10 SCIENCE PART 1 SOLUTIONS

CHAPTER 6 Control and Coordination KSEEB SSLC CLASS 10 SCIENCE PART 1 SOLUTIONS, English medium Karnataka state board,the Answers Are Prepared By Our Teachers Which Are Simple ,Pointwise,Easy To Read And Remember.

CHAPTER 6 Control and Coordination KSEEB SSLC CLASS 10 SCIENCE PART 1 SOLUTIONS

What is the difference between a reflex action and walking?

Difference between a reflex action and walking:

Reflex action: Quick and automatic response to a stimulus without conscious thought.
Walking: Voluntary movement controlled by the brain, involving conscious decision-making and muscle coordination.
Reflex actions are rapid and stereotyped, while walking requires deliberate planning and coordination.
Reflex actions involve a simple neural pathway through the spinal cord, while walking requires complex signals from the brain.
Examples of reflex actions include pulling hand away from a flame, while walking involves purposeful movement to travel from one place to another.

What happens at the synapse between two neurons?

What happens at the synapse between two neurons:

Electrical impulse travels down the axon of the presynaptic neuron.
Neurotransmitters are released into the synaptic gap.
Neurotransmitters bind to receptors on the postsynaptic neuron.
Binding generates a new electrical impulse in the postsynaptic neuron.
The impulse continues along the postsynaptic neuron, transmitting the signal.

Which part of the brain maintains posture and equilibrium of the body?

Part of the brain maintaining posture and equilibrium of the body:

The cerebellum, located in the hindbrain, maintains posture and balance.
It receives sensory input and coordinates muscle movements for stability and smooth voluntary actions.

How do we detect the smell of an agarbatti (incense stick)?

How we detect the smell of an agarbatti (incense stick):

Olfactory receptors in the nose detect molecules from the agarbatti.
Signals are sent to the brain’s olfactory bulb for processing.
The brain interprets these signals, allowing us to perceive the smell.

What is the role of the brain in reflex action?

Role of the brain in reflex action:

The brain modulates and coordinates reflex actions.
While reflex arcs bypass the brain for rapid response, the brain can influence their intensity and duration.
In complex reflexes, the brain integrates sensory information and modifies motor output.
It ensures reflex actions are appropriate and adaptive to the situation, maintaining accuracy for effective responses.

What are plant hormones?

. Plant hormones:

Chemical compounds produced by plants to regulate growth, development, and responses to the environment.
They act as signaling molecules, coordinating various physiological processes in plants.
Plant hormones include auxins, gibberellins, cytokinins, abscisic acid, and ethylene.
They are synthesized in one part of the plant and transported to other parts where they exert their effects.

How is the movement of leaves of the sensitive plant different from the movement of a shoot towards light?

Difference between the movement of leaves of the sensitive plant and shoot towards light:

Movement of leaves of the sensitive plant is immediate and rapid in response to touch, involving no growth.
The movement of shoots towards light is slower and involves directional growth, known as phototropism.
Sensitivity of the sensitive plant to touch leads to rapid folding of leaves, whereas light triggers directional growth in shoots

Give an example of a plant hormone that promotes growth.

Example of a plant hormone that promotes growth:

Gibberellins are plant hormones that promote stem elongation and cell division, leading to overall growth.
They are involved in seed germination, stem growth, and flowering.

How do auxins promote the growth of a tendril around a support?

. How auxins promote the growth of a tendril around a support:

Auxins are hormones that promote cell elongation and growth.
When a tendril of a plant comes in contact with a support, auxin concentration increases on the side away from the support.
This higher concentration of auxin stimulates cell elongation on the side away from the support, causing the tendril to curve and wrap around the support.

Design an experiment to demonstrate hydrotropism.

Experiment to demonstrate hydrotropism:

Place freshly germinated bean seeds on a wire mesh covering the neck of a conical flask filled with water.
Position the setup in a cardboard box open from one side, facing light from a window.
Observe and record the direction of shoot and root growth after a few days.
Rotate the flask so that shoots are away from light and roots towards light, and observe any changes in growth direction.
Conclusion: The experiment demonstrates hydrotropism, as the roots grow towards water and shoots away from water, regardless of light direction.

How does chemical coordination take place in animals?

Chemical coordination in animals:

Hormones are released by endocrine glands.
These hormones are secreted directly into the bloodstream.
They travel to target organs or tissues.
Hormones elicit specific responses in these target areas.
This allows for widespread and coordinated changes in the body’s functions and activities.
Examples of hormones include adrenaline, insulin, growth hormone, and testosterone.
Hormones help regulate various processes such as metabolism, growth, development, and stress response.

Why is the use of iodised salt advisable?

. Importance of iodised salt:

Iodine is essential for the production of thyroxin hormone in the thyroid gland.
Thyroxin regulates metabolism, including carbohydrate, protein, and fat metabolism.
Lack of iodine in the diet can lead to conditions like goitre.
Goitre results in a swollen neck due to an enlarged thyroid gland.
Iodised salt ensures an adequate intake of iodine, preventing thyroid-related disorders.
Thyroid hormones are crucial for maintaining proper growth and development in humans.

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

Response of the body to adrenaline secretion:

Adrenaline, also known as epinephrine, is secreted by the adrenal glands.
It is released into the bloodstream during stress or danger (fight or flight response).
Adrenaline increases heart rate, leading to more oxygen supply to muscles.
Blood flow to the digestive system and skin decreases, redirecting it to skeletal muscles.
Breathing rate increases due to contractions of the diaphragm and rib muscles.
These responses prepare the body to react quickly and effectively to the stressful situation.

Why are some patients of diabetes treated by giving injections of insulin?

. Treatment of diabetes with insulin injections:

Diabetes is a condition characterized by high blood sugar levels.
It can result from inadequate insulin production (Type 1 diabetes) or ineffective insulin action (Type 2 diabetes).
Insulin is a hormone produced by the pancreas.
It helps regulate blood sugar levels by facilitating the uptake of glucose into cells.
Patients with diabetes may require insulin injections to supplement insufficient insulin production or to overcome insulin resistance.
Insulin injections help lower blood sugar levels and prevent complications associated with uncontrolled diabetes, such as nerve damage, kidney disease, and cardiovascular problems.

EXERCISES

Which of the following is a plant hormone?

(a) Insulin

(b) Thyroxin

(d) Cytokinin.

. (d) Cytokinin is a plant hormone.

The gap between two neurons is called a

(a) dendrite.

(b) synapse.

(d) impulse.

(b) The gap between two neurons is called a synapse.

The brain is responsible for

(a) thinking.

(b) regulating the heart beat.

(d) all of the above.

(d) The brain is responsible for thinking, regulating the heartbeat, and balancing the body.

What is the function of receptors in our body? Think of situations where receptors do not work properly. What problems are likely to arise?

Receptors in our body detect information from the environment and send signals to the brain or spinal cord for processing. If receptors do not work properly, problems like impaired sensation, inability to detect stimuli (e.g., heat, pressure, pain), and coordination issues may arise

Draw the structure of a neuron and explain its function.

. Structure of a neuron:

Neurons consist of a cell body, dendrites, and an axon.
Dendrites receive signals from other neurons or sensory receptors.
The axon transmits electrical impulses away from the cell body to other neurons, muscles, or glands.
Function: Neurons transmit information in the form of electrical impulses throughout the nervous system, enabling communication between different parts of the body.

How does phototropism occur in plants?

. Phototropism in plants occurs when plant growth responds to light:

Auxin, a plant hormone, accumulates on the shaded side of the plant when exposed to light.
This uneven distribution of auxin causes cells on the shaded side to elongate, resulting in bending towards the light source.
Phototropism helps plants maximize light absorption for photosynthesis and optimize growth towards light sources.

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

Signals between the brain and the rest of the body will get disrupted.
Reflex actions might still occur, but voluntary actions may be lost.
Messages from sense organs to the brain for processing will be interrupted.

How does chemical coordination occur in plants?

Chemical coordination in plants happens through hormones.
Hormones like auxin, gibberellins, and cytokinins regulate growth and responses to the environment.
Auxin, for example, helps in elongating cells to bend towards light.

What is the need for a system of control and coordination in an organism?

Control and coordination are needed for an organism to respond to changes in its environment.
It helps in maintaining internal balance (homeostasis).
Enables organisms to carry out various activities like movement, growth, and reproduction effectively.

How are involuntary actions and reflex actions different from each other?

Involuntary actions are those we don’t consciously control, like heartbeats and digestion.
Reflex actions are immediate responses to stimuli, like pulling your hand away from a hot surface.
Involuntary actions are continuous and ongoing, while reflex actions are quick and automatic.

Compare and contrast nervous and hormonal mechanisms for control and coordination in animals.

Nervous system: Uses electrical impulses to transmit messages quickly.
Hormonal system: Relies on chemical signals (hormones) carried by the bloodstream.
Nervous system is fast but short-lived, while hormonal system is slower but longer-lasting.
Both systems work together to regulate body functions and respond to changes in the environment.

What is the difference between the manner in which movement takes place in a sensitive plant and the movement in our legs?

Sensitive plant: Movement occurs rapidly in response to touch without growth.
Our legs: Movement involves muscle contraction and relaxation to walk or run.
Sensitive plant movement is due to changes in cell shape, while leg movement involves muscle contraction controlled by nerves.