IBDP Biology- Decision making and learning

In this IBDP Biology blog post, we will be looking at the relationship between inheritance and learning, as well as the decision making process of the Central Nervous System.

The role of inheritance and learning 

Chaffinches, or Fringilla coelebs, birdsong: partly innante/partly learned male chaffinches use song to deter males from entering their territory and to attract mates.

Song varies somewhat between males which allows identification of male. Also differs from other related species

• rear some chaffinches in boxes where they can hear other adult male chaffinches singing
• rear other chaffinches in isolated, sound-proof box

Chaffinch song shows some relationship to normal song

• correct length
• correct number of notes

Chaffinch song shows some features that differ from normal song

• narrower range of frequencies
• fewer distinctive phrase 

Length and number of notes of song are innate and Frequencies + distinctive phrases are learned from other chaffinches 

Decision-making in the CNS

Synapses are the sites of decision-making.

• A post-synaptic neuron's membrane potential is the summation of input from pre-synaptic neurons:
• EPSPs depolarize post-synaptic neurons
• IPSPs hyper-polarize post-synaptic neurons

If the post-synaptic neuron reaches threshold potential at its axon hillock, it will produce an action potential.

Pre-synaptic neurons can vary in the frequency, but not intensity of their input, since action potentials are "all-or-none" 

That is all for this blog!

CLICK HERE TO LEARN MORE ABOUT OUR IBDP BIOLOGY COURSES

References:

• https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.wildlifetrusts.org%2Fwildlife-explorer%2Fbirds%2Ffinches-and-buntings%2Fchaffinch&psig=AOvVaw1ykWW8fW-zMfbZZhBpvl94&ust=1627301115855000&source=images&cd=vfe&ved=0CAsQjRxqFwoTCKC79ZyX_vECFQAAAAAdAAAAABAN
• https://www.google.com/url?sa=i&url=http%3A%2F%2Fwww.old-ib.bioninja.com.au%2Foptions%2Foption-e-neurobiology-and-2%2Fe4-neurotransmitters-and.html&psig=AOvVaw2f24Q3ZD3mmEbbeqkfDFmF&ust=1627301205174000&source=images&cd=vfe&ved=0CAsQjRxqFwoTCPCmgMeX_vECFQAAAAAdAAAAABAD

Drafted by Venetia (Biology)