Flashcards in Coordination Deck (26):
How does nervous and hormonal communication occur?
Through cell signalling and cellular communication.
What is a target cell?
A cell that receives and is affected by a chemical message sent from another cell.
What are the 2 ways cells can transfer signals between each other?
1) Locally between neurones across synapses.
2) Across large distances using hormones.
What are the 4 ways cell signalling occurs?
1) Autocrine- cell targets itself
2) Signalling across gap junctions- cell targets a cell connected by gap junctions
3) Paracrine- cell targets a nearby cell
4) Endocrine- cell targets a distant cell via the bloodstream
The nervous system is responsible for detecting what?
Internal and external changes to the body
What are stimuli?
Changes to the body detected by nervous system
What pathway does an electrical impulse take?
Receptor, Sensory neurone, Relay neurone, Motor neurone, Effector cell
What are the three types of neurones?
A sensory neurone carries impulses from.........to............?
From receptor organs to relay/motor neurones or he brain and CNS.
A relay neurone carries impulses from.........to............?
From sensory neurone to motor neurone
A motor neurone carries impulses from.........to............?
From CNS to effectors
Name one internal factor that causes a response in plants? In animals?
Plants- water potential
Animals- internal temperature
Why is coordination required in multicellular organisms?
Few body systems work in isolation. For example,
Muscles need oxygen to contract
Oxygen is transported in RBC
RBC are made in bone marrow by stem cells
How do cells communicate in animals, and in plants?
Animals- nervous system by electrical impulses
Plants- hormonal system by chemical messengers
Name some factors in the environment that we respond to?
What is the cell body of a neurone?
Contains a nucleus and is surrounded by cytoplasm. Also contains Endoplasmic Reticulum and mitochondria.
What are the dendrons of a neurone?
Short extensions that come from the cell body.
What are dendrites of a neurone?
Smaller branches extending off the dendrons that transmit impulses towards the cell body
What is the axon of a neurone?
Singular, elongated nerve fibres that transmit impulses away from the cell body
Name some internal environments that change.
Blood glucose concentration
What s homeostasis?
The functions of organs are coordinated to maintain a relatively constant internal environment.
What are myelinated neurones?
Neurones with axons covered in myelinated sheath.
What cell causes a double bilayer of phospholipids to be laid down every time it grows around the axon?
How do myelinated neurones help transmit impulses faster?
The impulse jumps along the gaps between the schwann cells called the node of Ranvier.
What is Multiple sclerosis?
An autoimmune disease involving the breakdown of myelin sheath on axons of neurones in the brain.