Year 9 MYP Homeostasis Notes (copy)

What is homeostasis?

The process of maintaining a stable internal environment despite external changes.

What conditions are regulated by body systems?

Water balance, temperature, energy, oxygen, and waste levels.

What are the smallest living structures capable of self-maintenance?

Cells.

What forms when cells of the same type work together?

Tissues.

What is an organ?

A structure made of tissues working together.

What is a system in biology?

A group of organs working collectively.

What cells transmit impulses rapidly within the nervous system?

Neurons.

What are neuroglial cells?

Support cells in the nervous system.

What do photoreceptors detect?

Light.

What do mechanoreceptors detect?

Touch, pressure, and sound.

What do thermoreceptors sense?

Variations in temperature.

What do chemoreceptors respond to?

Chemical stimuli (e.g., taste and smell).

What do pain receptors detect?

Harmful stimuli, indicating danger or injury.

What is the importance of maintaining stable internal conditions?

Body functions optimally when internal conditions are stable.

What components are involved in the stimulus-response model?

Stimulus, receptor, control centre, effector, response.

What is negative feedback?

Opposes change to return to normal.

What is positive feedback?

Amplifies change until an endpoint is reached.

What comprises the central nervous system (CNS)?

The brain and spinal cord.

What is the role of the peripheral nervous system (PNS)?

Carries messages to and from the CNS.

Which part of a neuron receives signals from other neurons?

Dendrites.

What does the axon do in a neuron?

Transmits impulses away from the cell body.

What is the function of the myelin sheath?

Insulates axon for faster signal transmission.

What is a synapse?

Junction where signals are passed between neurons.

How are neural impulses generated?

By electrical impulses generated by ion movement.

What are neurotransmitters?

Chemicals released at synapse to relay messages to the next neuron.

What do sensory neurons do?

Relay sensory information from the PNS to the CNS.

What is the function of interneurons?

Connect sensory and motor neurons within the CNS.

What do motor neurons carry?

Messages from the CNS to effectors (muscles and glands).

What is a reflex arc?

Pathway for reflex actions that bypasses the brain.

What does a reflex arc involve?

A sensory neuron, interneuron (in spinal cord), and motor neuron.

What is the definition of tissue?

Group of similar cells performing a specific function.

What is the definition of an organism?

Multitude of systems working together to form a living being.

What is a key role of sense organs?

Detect stimuli from the environment.

What do chemoreceptors respond to?

Chemical stimuli.

What regulates water balance in the body?

Homeostasis.

What is the relationship between systems and homeostasis?

Systems must detect and respond appropriately to maintain homeostasis.

What is an effector in the stimulus-response model?

Organs, glands, or tissues executing the adjustments.

What happens during negative feedback?

It opposes change to return to normal.

What is an example of positive feedback?

Childbirth, blood clotting.

What makes up the nervous system?

Neurons and neuroglial cells.

How are reflex actions characterized?

By quick responses to stimuli.

What is metacognition?

Thinking about one's own learning processes.

What type of neurons are responsible for carrying messages from the CNS to muscles?

Motor neurons.

What do pain receptors indicate?

Danger or injury.

How do systems work together in the body?

They collaborate towards common goals such as excretion, digestion, and respiration.

What type of cells form tissues?

Cells of the same type.

What is the role of the control center in the stimulus-response model?

Regulates the output to adjust for changes.

What is maintained through homeostatic processes?

A stable internal environment.

Where are neurotransmitters released?

At the synapse.

What detects light?

Photoreceptors.

What is the role of sensory neurons?

To relay sensory information.

What type of feedback mechanism can enhance processes until a certain point is achieved?

Positive feedback.

What do neurons connect with at the synapse?

Other neurons.

What is the primary purpose of homeostasis?

To ensure body functions optimally.

Define the term 'organ.'

A structure made up of different types of tissues.

What do the brain and spinal cord constitute?

The central nervous system (CNS).

What is the function of dendrites?

To receive signals.

How does a reflex arc contribute to quick responses?

By bypassing the brain.

Identify a regulated condition significant for survival.

Oxygen levels.

How many types of neurons are there?

Three main types: sensory, interneurons, and motor neurons.

What are groups of similar tissues that work together called?

Organs.

What is the primary function of the central nervous system?

To process and respond to sensory information.

What are the two main types of feedback mechanisms?

Negative feedback and positive feedback.

What role do neuroglial cells play?

To support neurons in the nervous system.

What are examples of stimuli detected by sense organs?

Light, sound, touch, taste, smell.

How does the nervous system function in maintaining homeostasis?

By detecting changes and coordinating responses.

What effect do neurotransmitters have in the nervous system?

They relay messages between neurons.

Define 'cell.'

The basic unit of life.

In what part of the plant does the process of homeostasis occur?

Throughout the organism.

What defines a living being organisms?

The collaboration of multiple systems.

What do receptors do in the body?

Detect changes in the environment.

What organ systems are involved in homeostasis?

Various systems including circulatory, respiratory, and excretory systems.

What occurs at the synapse between neurons?

Transmission of signals via neurotransmitters.

What type of stimuli do temperature receptors sense?

Heat and cold.

What is the main task of sensory neurons in the nervous system?

To carry information from sense organs to the CNS.

What is the relationship between tissues and organs?

Organs are composed of different types of tissues.

What are the basic components of the nervous system?

Neurons and neuroglial cells.

What is the function of the axon in a neuron?

To transmit impulses away from the cell body.

What do mechanoreceptors respond to?

Touch and pressure.

What are conditions that need to be regulated for optimal body function?

Temperature, energy, water balance, oxygen and waste levels.

What are three examples of regulated conditions in the body?

Water balance, energy, and oxygen levels.

What is the function of the central nervous system?

To integrate and coordinate bodily functions.

What is an example of a system in the human body?

The digestive system.

How does the body typically respond when a dangerous stimulus is detected?

Through reflex actions.

What is an example of negative feedback in the body?

Regulating body temperature.

What does an effector do in the stimulus-response model?

Executes the adjustments needed in response to a stimulus.