C3.1 - integration of body systems (6a)

Question 1

Why is system integration a necessary process in living systems?

Answer 1

• coordination is needed for component parts of a system to collectively perform an overall function
• communication between component parts is an essential part of this coordination

Question 2

What is the hierarchy of subsystems in multicellular organisms?

Answer 2

1. Cells
2. Tissues
3. Organs
4. Body systems

Question 3

Why is the integration of these different subsystems responsible for emergent properties?

Answer 3

Each level of organisation allows greater efficiency and complexity

Question 4

What are emergent properties?

Answer 4

Properties that are created when all the component parts are integrated, and do not exist within the individual components

Question 5

How are organs integrated in animal bodies?

Answer 5

• signalling between different cells, tissues and organs of the body
  E.g) hormone signalling using the endocrine system
  E.g) nervous signalling using the nervous system
• transport of materials and energy
  E.g) hormones are transported to target organs in the plasma of the blood system
  E.g) oxygenis transported between organs by haemoglobin within erythrocytes, using the blood system

Question 6

What are the similarities between the nervous system and the endocrine system?

Answer 6

• both are used for communication between different cells, tissues and organs of the body
• both cause a response in specific target cells when chemicals (hormones or neurotransmitters) bind to receptors
• both can stimulate or inhibit processes in target cells
• both can work over long distances
• both are under overall control of the brain
• both use feedback mechanisms and are involved in homeostasis

Question 7

What are the characteristics of the endocrine system in terms of:
Type of message
Location of transport
Carried to
Range of organs affected
Relative speed
Duration
Voluntary response

Answer 7

Type of message - chemical
Location of transport - blood plasma
Carried to - whole body
Range of organs affected - all/wide range affected
Relative speed - slower
Duration - long term
Voluntary response - never

Question 8

What are the characteristics of the nervous system in terms of:
Type of message
Location of transport
Carried to
Range of organs affected
Relative speed
Duration
Voluntary response

Answer 8

Type of message - electrical impulses
Location of transport - within/by neurons
Carried to - specific cells such as muscle fibres
Range of organs affected - only muscles and glands receive signals
Relative speed - faster
Duration - short term
Voluntary response - sometimes

Question 9

Why is the brain considered the central information integration organ?

Answer 9

The brain has roles in:
- processing information combined from several inputs
- learning and memory

Question 10

What is the role of the cerebral hemispheres?

Answer 10

Integration of high-order, complex functions (learning, memory and emotions)

Question 11

What is the role of the hypothalamus?

Answer 11

Maintains homeostasis by controlling the pituitary gland

Question 12

What is the role of the cerebellum?

Answer 12

Motor control and coordination of balance

Question 13

What is the role of the medulla oblongata?

Answer 13

Controls automatic functions (swallowing, breathing rate and heart rate)

Question 14

What is pituitary gland?

Answer 14

Stores and secretes hormones

Question 15

What is the role of the celebral cortex?

Answer 15

Perceiving and responding to the environment, allowing voluntary control of some automatic functions such as swallowing (surface layer of the hemispheres)

Question 16

How is the endocrine system controlled?

Answer 16

The hypothalamus controls the endocrine system by maintaining homeostasis by controlling the pituitary gland, through secretion of hormones that stimulate or inhibit hormones released by the pituitary gland

Question 17

What is the role of the pituitary gland?

Answer 17

Stores and secretes hormones, from one of two glands
Anterior pituitary - FSH and LH/ Growth hormones
Posterior pituitary - oxytocin / ADH

Question 18

What are sensory neurons?

Answer 18

Convey electrical impulses from receptor cells to the central nervous system

Question 19

What are motor neurons?

Answer 19

Convey electrical impulses from the celebral hemispheres to muscles and glands

Question 20

What is the neuromuscular junction?

Answer 20

A synapse between a motor neuron and a muscle fibre

Question 21

What is the neuromuscular junction?

Answer 21

A synapse between a motor neuron and a muscle fibre

Question 22

What are the inputs and outputs for the integration hormones?

Answer 22

1. Each receptor we perceive consciously has a specific pathway to the central nervous system.
2. Motor neurons from the celebral hemispheres terminate at muscles, forming a neuromuscular junction. The muscles are stimulated to contract.

Question 23

What is the structure of nerves?

Answer 23

Nerves are a bundle of nerve fibres of both sensory and motor neurons.
- Neurons are cells, but nerves are bundles of neurons, so are a tissue.

• Both myelinated and non-myelinated nerve fibres may occur in the same nerve.
• The bundles of fibres are within a protective sheath.

Question 24

What is the structure of nerves?

Answer 24

Nerves are a bundle of nerve fibres of both sensory and motor neurons.
- Neurons are cells, but nerves are bundles of neurons, so are a tissue.

• Both myelinated and non-myelinated nerve fibres may occur in the same nerve.
• The bundles of fibres are within a protective sheath.

Question 25

What is the integrating centre for unconscious processes?

Answer 25

The spinal cord

Question 26

What are conscious processes?

Answer 26

In conscious processes, the cerebral hemispheres are involved in the pathway, causing the organism to be aware of perceiving the stimulus and deciding how to respond.

Question 27

What are unconscious processes?

Answer 27

In unconscious processes, the integration happens in the grey matter (neurons and synapses) of the spinal cord. There is no perception of the decision, because the cerebral hemispheres of the brain are not involved. The response is involuntary.

Question 28

What is the input to the spinal cord and cerebral hemispheres?

Answer 28

Sensory neurons convey electrical impulses from receptor cells to the central nervous system.
Each receptor we perceive consciously has a specific pathway to the central nervous system.

Question 29

What is the output from cerebral hemispheres?

Answer 29

The output from the cerebral hemispheres to muscles occurs through motor neurons.
Motor neurons from the cerebral hemispheres terminate at muscles, forming a neuromuscular junction.

Question 30

What is the pain reflex arc as an example of an involuntary response?

Answer 30

1. Pain receptors in the hand are free sensory neuron endings.
2. There is a single inter-neuron in the grey matter of the spinal cord.
3. Skeletal muscle is the effector.

Question 31

What is the role of the pineal gland?

Question 32

How does epinephrine (adrenaline) prepare the body for vigorous activity?

Question 33

What is the feedback control of the heart rate?

Question 34

What is the feedback control of the ventilation rate?

Question 35

How is peristalsis controlled in the digestive system?