Definitions

Question 1

What is the definition of Biological Rhythms?

Answer 1

Cyclical patterns within biological systems
Evolved in response to environmental influences, e.g. day & night
Endo & exogenous pacemakers govern it

Question 2

What is the definition of Circadian Rhythms?

Answer 2

1 biological rhythm = 24 hour circadian rhythm (AKA Body clock) which is reset by levels of light

Circadian rhythms = sleep-wave cycle & body temperature

Question 3

What is the definition of Infradian Rhythms?

Answer 3

Last longer than 24 hours & can be weekly, monthly or annually
E.g. female menstrual cycle

Question 4

What is the definition of Ultradian Rhythms?

Answer 4

Lasts less than 24 hours & can be found in pattern of human sleep
Cycle alternates between REM & NREM sleep & consists of 5 stages
Light sleep —> Deep Sleep —> REM Sleep (brain waves speed as dreams occur)
Repeats itself every 90 minutes through night - up to 5 cycles

Question 5

What is the definition of Endogenous Pacemakers?

Answer 5

Internal mechanisms governing biological rhythms, particularly circadian sleep-wake cycle
Endo can be altered & affected by environment
Most important Endo is suprachiasmatic nucleus - closely linked to pineal gland, influence to maintain circadian sleep-wake cycle

Question 6

What is the definition of Exogenous Zeitgebers?

Answer 6

Influence biological rhythms
Environmental events responsible for resetting biological clock of organism. Including social cues, like meal times & social activities
Most zeitgeber is light, responsible for resetting body clock each day, keeping it on 24 hour cycle

Question 7

What is the definition of homeostasis?

Answer 7

Any self-regulating process where an organism tends to maintain stability while adjusting to conditions that are best for survival

Example = Normal body temperature is 37 °C (98.6 °F), - number of factors can affect value, including exposure to elements & hormones

Question 8

What is the definition of Suprachiasmatic Nuclei?

Answer 8

Bilateral structure located in anterior part of hypothalamus
Central pacemaker of circadian timing system & regulates most circadian rhythms in body

Question 9

What is the definition of Melanopsin?

Answer 9

Protein in the eye, sensitive to light & carries signals to the Suprachiasmatic Nuclei to set 24-hour daily body cycle
Social cues, like mealtimes, also act as zeitgebers - humans can compensate for lack of natural light, by using social cues instead

Question 10

What is the definition of Broca’s area?

Answer 10

Found in left frontal lobe & thought to be involved in language production

Question 11

What is the definition of Wernicke’s area?

Answer 11

Found in left temporal lobe & thought to be involved in language processing/comprehension

Question 12

What is synaptic transmission?

Answer 12

Process by which 1 neuron communicates with another. Info passed down neuron axon as electrical impulse known as action potential. Once action potential reaches end of axon it needs to be transferred to another neuron/tissue.
It must cross over the synaptic gap between presynaptic neuron & post-synaptic neuron.
At end of neuron (in axon terminal) are synaptic vesicles, which contain chemical messengers - neurotransmitters.
When electrical impulse (action potential) reaches these synaptic vesicles, they release their contents of neurotransmitters. Neurotransmitters then carry signal across synaptic gap.
They bind to receptor sites on post-synaptic cell, thereby completing synaptic transmission.