C3.1 Integration of Body Systems Flashcards
Define system integration
Different systems in an organism need to effectively communicate and coordinate with each other to be able to perform an overall function.
How do emergent properties work?
They are created when the sum of all the parts creates features that do not exist within the individual components.
Examples of emergent properties
- Cells specialized/adapted to perform specific functions
- Tissues made from a group of cells of the same type to carry out a function
- Organs made from a group of tissues that work together to carry out a specific function of life
- Body systems made from groups of organs that interact with each other to perform an overall function of life
- An organism is a living individual made up of organ systems
What are the features of hormonal signaling?
- Chemical signaling, secreted by endocrine glands
- In the bloodstream
- Widespread: to all parts of the body that are supplied with blood, but only certain cells respond
- Effect target cells
- Type of response: growth, development, reproduction, metabolic rate and heat generation
- Slow
- Long, until the hormone is broken down
What are the features of nervous signalling?
- Electrical, by passage of cations across membranes
- Happens in neurons
- Highly focused: one specific neuron or group of effector cells
- Effects muscles (contraction)
- Fast
- Short unless nerve impulses are sent repeatedly
What is the role of the blood system in transporting materials between organisms?
- RBC:
- Transport O2 from lungs to all tissues
- Transport CO2 back to the lungs - Blood plasma:
- Transport water to all tissues
- Transport nutrients and inorganic ions to all cells
- Transport metabolic waste products from liver to kidneys
- Transport hormones from endocrine glands to target organs
- Distribution of heat
- Transports dissolved proteins that regulate osmotic concentration and antibodies
What is the role of the brain?
It is the central information integration organ.
1. The brain receives impulses from sensory receptors
2. The information is then processed, stored and instructions are sent out to all parts of the body to coordinate life processes.
3. Signals are sent through motor neurons to effector organs (muscles or glands) which execute responses.
What is the role of the frontal lobe?
motor control, problem solving, speech production.
What is the role of the temporal lobe?
auditory processing, language comprehension, memory/ info retrieval
What is the role of the brainstem?
involuntary responses
What is the role of the parietal lobe?
touch perception, body orientation and sensory discrimination
What is the role of the occipital lobe?
sight, visual reception and interpretation
What is the role of the cerebellum?
- Coordinates skeletal muscle contraction
- Controls balance and help maintain posture
- Helps in activities requiring motor memory
What is the role of the spinal cord?
It is an integrating center for unconscious processes.
– carries nerve impulses between brain and rest of body
– controls reflexes without input from the brain
What is the role of sensory neurons?
Convey messages from receptor cells to central nervous system
What are the tissues in the spinal cord?
White matter: transmits signals from sensory receptors to brain and vice versa.
Grey matter: where info integration happens
What happens in input to cerebral hemispheres?
The left cerebral hemisphere receives sensory input from sensory receptors in the right side of the body and the right eye and vice versa for the right cerebral hemisphere.
What happens in output of cerebral hemisphere?
The primary motor cortex sends signals via motor neurons to each striated muscle in the body for locomotion and controlling posture. The dendrites in the motor neurons receive signals from various relay neurons and send them to the cell body. When a nerve impulse reaches the axon’s end, it triggers muscle contraction and gland secretion.
What are nerves?
Bundles of nerve fibres surrounded by a protective sheath of both sensory and motor neurons.
Outline the reflex arc
- Receptor cells or nerve endings of some sensory neurons detect a stimulus
- Sensory neurons receive signals coming from the receptor cells. These neurons have long axons that carry nerve impulses from the receptor to the spinal cord or brain.
- Interneurons in the gray matter of the CNS receives, processes the signals and make decisions about appropriate responses
- Motor neurons receive signals from interneurons via synapses
- If a threshold potential is achieved in a motor neuron, an impulse is sent to the effector (skeletal muscles) which will carry out a response. There are two types of responses: muscle contraction and gland secretion
What is the circadian rhythm?
A 24 hour cycle that continues even if a person is placed experimentally continuous light or darkness
What is melatonin?
- Hormone secreted by pineal gland that controls circadian rhythms
- Its release is inhibited due to exposure of light
What is the sleep-wake cycle?
- Secretion increases in the evening, and high levels of melatonin causes drowsiness, promoting sleep.
– Melatonin decreases at dawn, encouraging wakefulness.
– High levels of melatonin contributes to nighttime drops in body temperature
– High levels of melatonin decrease urine production at night.
What is the knock-on effect?
The release of melatonin has also a knock-on effect on several other metabolic or homeostatic functions in the body by stimulating body temperature, hunger and acetylcholine production.
