1. Asas Biologi Dalam
Tingkah Laku
MINGGU 2

2. BIOPSYCHOLOGY
• Kajian saintifik tentang hubuungkait biologi
dan tingkah laku
• Contoh persoalan:
– Kenapa rasa lapar?
– Apabila rasa sangat lapar, apa yang anda rasa?
• Isu penting dalam biopsychology:
– Struktur dan fungsi neuron
– Struktur dan fungsi sistem saraf
– Sistem endokrin

3. NEURON
(Cell Body)

4. STRUKTUR ASAS NEURON
• Bagaimanakah maklumat yang diterima
melalui deria boleh menghasilkan tindak balas
tubuh badan, sensation (perasaan), dan
tingkah laku overt?
• Ini semua disebabkan oleh NEURON.
• Neuron terbahagi kepada 3 bahagian:
1. Cell Body (Soma)
2. Axon
3. Dendrite

5. STRUKTUR ASAS NEURON
• Dendrite membawa maklumat ke cell body,
axon pula membawa maklumat dari cell body
ke axon terminal.
• Komunikasi neuron adalah satu hala.
• Axon diliputi oleh myelin sheath.
• Antara myelin sheath ada ruang (gap).
• Myelin sheath dan ruang ini memainkan
peranan penting dalam menentukan sejauh
mana maklumat dapat dipindahkan.

6. STRUKTUR ASAS NEURON
• Dalam myelin sheath juga mengandungi set
neuron yang disebut sebagai glial cells.
• Hujung axon terbahagi kepada cabang yang
disebut sebagai axon terminals yang rapat
kedudukannya tetapi tidak menyentuh neuron
yang lain.
• Ruang antara hujung axon terminal dengan
neuron yang lain disebut sebagai synapse.

7. STRUKTUR ASAS NEURON

8. FUNGSI ASAS NEURON

9. KOMUNIKASI DALAM NEURON

10. • Apabila neuron dalam keadaan rehat, terdapat
sejumlah kecil cas elektrik (-70 millivolts) dalam cell
membrane .
• Cas elektrik ini disebabkan banyak ion positif dan
negatif wujud di luar dan di dalam sel. Keadaan ini
menghasilkan cas negatif dalam membrane cell,
manakala di luarnya adalah cas positif.
• Neuron terus berkerja bagai memastikan keadaan
resting potential dan action potential sentiasa
berterusan iaitu dengan mengepam ion positif balik ke
luar setelah memasuki cell, dan mengepam masuk
semula ion negatif yang telah keluar dari cell secara
terus menerus.

11. • Komunikasi dalam neuron bergerak dari axon
ke axon melalui ruang antara axon yang
disebut sebagai nodes of ranvier.
• Kelajuan komunikasi ini menjangkau 270 batu
per jam.

12. KOMUNIKASI ANTARA NEURON

13. • Proses action potential berlaku sepanjang axon
hingga ke axon terminal.
• Di antara axon terminal terdapat banyak struktur
synaptic vesicles yang mengandungi
neurotransmitter yang membawa maklumat
neuron ke hujung axon terminal.
• Neurotransmitter ini dilepaskan ke synapse
(ruang antara axon terminal dengan dendrite
neuron lain).
• Action potential terus berlaku dalam perjalanan
neurotransmitter melalui synapse ini.

14. • Neurotransmitter ini kemudiannya sampai ke bahagian
penerima (receptor) yang terletak di hujung dendrite
neuron lain, dan terus bergabung.
• Bahagian penerima ini adalah sejenis molekul protein
yang kompleks, yang hanya menerima unsur-unsur
kimia yang sepadan dengannya.
• Oleh itu neurotransmitter tidak semestinya
melepaskan maklumat melalui synapse terus kepada
neuron terdekat tetapi boleh juga melepaskannya
melalui body fluids ke sel-sel yang lain.

15. • Selepas neurotransmitter dilepaskan ke
synapse mungkin akan berlaku 2 keadaan:
– Sama ada ia di ambil balik masuk ke dalam axon
terminal asal (reuptake), atau
– Ia di nyahktifkan oleh enzim-enzim yang terdapat
di ruangan synapse.

16. • Jika neurotransmitter mengandungi unsur yang
bersifat excitatory, maka proses depolarization,
iaitu penghantaran maklumat dalam cell
membrane neuron kedua adalah menjadi lebih
aktif.
• Tetapi jika neurotransmitter mengandungi unsur
yang bersifat inhibitory, akan menyebabkan
hyperpolarize, iaitu penghantaran maklumat
dalam cell membrane neuron kedua menjadi
lemah.

17. • Synapses dan Dadah
Sesetngah jenis dadah menghasilkan kesan
psikologi dengan meningkatkan atau
mengurangkan kuantiti neurotransmitter di
ruang synapse. Terdapat jenis dadah yang
berkerja di bahagian penerima (receptor),
berperanan untuk menghalang atau mengganggu
penyerapan neurotransmitter. Contohnya, dadah
(dopamine) yang menghalang bahagian penerima
sebagai dapat mengurangkan simptom
skizofrenia.

18. NEUROTRANSMITTER: KUNCI BAHAN
KIMIA KE OTAK
• Sekurang-kurangnya terdapat 9 unsur bahan,
manakala 40 atau lebih peptides (kombinasi
asid amino) yang berfungsi sebagai
neurotransmitter.
• Setiap jenis neurotransmitter itu
mengandungi fungsi tertentu dan berada
dilokasi tertentu.

19. NEUROTRANSMITTER KESAN DAN LOKASI
Acetylcholine (ACh) Involved in a wide variety of behaviors and
emotions, including pleasure. Implicated in
schizophrenia and Parkinson’s disease. Distributed
widely throughout the central nervous system,
where it is involved in arousal, attention, memory,
motivation, and movement.
Dopamine Involved in muscle action through presence at
neuromuscular junctions (specialized type of
synapse where neurons
connect to muscle cells). Degeneration of neurons
that produce ACh have been linked to Alzheimer’s
disease.Too much can lead to spasms and tremors;
too little, to paralysis or torpor.

20. NEUROTRANSMITTER KESAN DAN LOKASI
Serotonin Involved in the regulation of sleep, dreaming, mood,
eating, pain, and aggressive behavior. Implicated in
depression.
Norepinephrine Affects arousal, wakefulness, learning, memory, and
mood.
Endorphins Involved in the inhibition of pain. Released during
strenuous exercise. May be responsible for
“runner’s high.”
Glutamate Involved in long-term memory and the perception of
pain.

21. NEUROTRANSMITTER KESAN DAN LOKASI
GABA
(Gamma amino butyric
acid)
A largely inhibitory neurotransmitter distributed
widely throughout the central nervous system.
Implicated in sleep and eating disorders. Low levels
of GABA have also been linked to extreme anxiety.
Glycene Principally responsible for inhibition in the spinal
cord and lower brain canters

22. SISTEM SARAF
(THE NERVOUS SYSTEM)
THE CENTRAL NERVOUS SYSTEM
(SISTEM SARAF PUSAT)
THE PERIPHERAL NERVOUS SYSTEM
(SISTEM SARAF PERIFERAL)

23. BAHAGIAN SISTEM SARAF

24. SISTEM SARAF PUSAT

25. • Sistem saraf pusat mengawal kebanyakan fungsi
tubuh dan minda.
• Mengandungi 2 bahagian iaitu otak dan tulang
belakang.
• Otak – pusat pemikiran, pentafsir persekitaran,
asas kawalan tubuh badan.
• Tulang belakang (spinal cord) – jalan
penghubung antara tubuh badan dan otak.
Membawa maklumat daripada receptor ke otak
melalui pelbagai jenis saraf dan membawa
maklumat dari otak ke otot dan kelenjar melalui
saraf juga. Kunci utama tindak balas refleks.

26. SISTEM SARAF PERIFERAL

27. • Mengandungi saraf, serta sejumlah axon
daripada neuron, yang menghubungkan
sistem saraf pusat dengan organ deria dan
dengan otot dan kelenjar di seluruh tubuh
badan.
• Terbahagi kepada 2 bahagian:
– Sistem Saraf Somatic
– Sistem Saraf Autonomic

28. • Sistem Saraf Somatic
– Menghubungkan sistem saraf pusat dengan otot
voluntary di seluruh tubuh badan.
• Sistem Saraf Autonomic
– Menghubungkan sistem saraf pusat dengan
kelenjar dan organ dalaman.
– Mengandungi 2 bahagian:
• Sistem Saraf Simpetatik
• Sistem Saraf Parasimpetatik

29. • Sistem Saraf Simpetatik:
– Menyediakan tubuh badan untuk menggunakan
tenaga, seperti dalam aktiviti fizikal.
– Rangsangan sistem ini mengakibatkan peningkatan
kadar nadi, dan peningkatan tekanan darah.
• Sistem Saraf Parasimpatetik
– Merangsang proses untuk menyimpan tenaga.
– Mengakibatkan kadar nadi perlahan, tekanan darah
menurun, dan peralihan darah keluar dari otot rangka
(seperti otot lengan dan kaki) ke sistem perkumuhan.

31. OTAK (THE BRAIN)

32. STRUKTUR OTAK

33. • Terdapat 4 stuktur utama otak iaitu:
– Cerebrum
– Cerebellum
– Brain stem
– Limbic System

34. Cerebrum
Bahagian Fungsi
Frontal Lobe Behavior, Abstract thought processes, Problem solving, Attention,
Creative thought, Some emotion, Intellect, Reflection, Judgment,
Initiative, Inhibition, Coordination of movements,
Generalized and mass movements, Some eye movements, Sense of
smell, Muscle movements, Skilled movements, Some motor skills,
Physical reaction, Libido (sexual urges)
Occipital Lobe Vision, Reading
Parietal Lobe Sense of touch (tactile senstation), Appreciation of form through
touch (stereognosis), Response to internal stimuli (proprioception),
Sensory combination and comprehension, Some language and
reading functions, Some visual functions

35. Bahagian Fungsi
Temporal Lobe Auditory memories, Some hearing, Visual memories, Some vision
pathways, Other memory, Music, Fear, Some language, Some
speech, Some behavior amd emotions, Sense of identity
Right
Hemisphere
(the
representation
al hemisphere)
The right hemisphere controls the left side of the body, Temporal
and spatial relationships, Analyzing nonverbal information,
Communicating emotion
Left
Hemisphere
(the categorical
hemisphere)
The left hemisphere controls the right side of the body, Produce and
understand language
Corpus
Callosum
Communication between the left and right side of the brain

36. Cerebellum
• Balance
• Posture
• Cardiac, respiratory, and vasomotor centers

37. The Brain Stem
• Underneath the limbic system is the brain
stem. This structure is responsible for basic
vital life functions such as breathing,
heartbeat, and blood pressure. Scientists say
that this is the "simplest" part of human
brains because animals' entire brains, such as
reptiles (who appear early on the evolutionary
scale) resemble our brain stem.

38. Bahagian Fungsi
Midbrain The rostral part of the brain stem, which includes the tectum and
tegmentum. It is involved in functions such as vision, hearing, eye
movement, and body movement. The anterior part has the cerebral
peduncle, which is a huge bundle of axons traveling from the
cerebral cortex through the brain stem and these fibers (along with
other structures) are important for voluntary motor function
Pons part of the metencephalon in the hindbrain. It is involved in motor
control and sensory analysis... for example, information from the
ear first enters the brain in the pons. It has parts that are important
for the level of consciousness and for sleep. Some structures within
the pons are linked to the cerebellum, thus are involved in
movement and posture.
Medulla
Oblongata
this structure is the caudal-most part of the brain stem, between
the pons and spinal cord. It is responsible for maintaining vital body
functions, such as breathing and heartrate

39. The Limbic System
• The limbic system, often referred to as the
"emotional brain", is found buried within the
cerebrum. Like the cerebellum, evolutionarily
the structure is rather old.
• This system contains the thalamus,
hypothalamus, amygdala, and hippocampus.
Here is a visual representation of this system,
from a midsagittal view of the human brain:

40. Bahagian Fungsi
Thalamus a large mass of gray matter deeply situated in the forebrain at the
topmost portion of the diencephalon. The structure has sensory and
motor functions. Almost all sensory information enters this
structure where neurons send that information to the overlying
cortex. Axons from every sensory system (except olfaction) synapse
here as the last relay site before the information reaches the
cerebral cortex.
Hypothalamus part of the diencephalon, ventral to the thalamus. The structure is
involved in functions including homeostasis, emotion, thirst, hunger,
circadian rhythms, and control of the autonomic nervous system. In
addition, it controls the pituitary.

41. Bahagian Fungsi
Amygdala- part of the telencephalon, located in the temporal lobe; involved in
memory, emotion, and fear. The amygdala is both large and just
beneath the surface of the front, medial part of the temporal lobe
where it causes the bulge on the surface called the uncus. This is a
component of the limbic system.
Hippocampus the portion of the cerebral hemispheres in basal medial part of the
temporal lobe. This part of the brain is important for learning and
memory . . . for converting short term memory to more permanent
memory, and for recalling spatial relationships in the world about us

42. SISTEM ENDOKRIN

43. • Hypothalamus memainkan peranan penting
dalam sistem endokrin.
• Kelenjar endokrin merembeskan hormon.
• Hormon yang berhubung dan memberi kesan
pada sistem saraf disebut – Neurohormones.
• Neurohormones sama seperti
neurotransmitter mempengaruhi aktiviti
neuro.

44. • Hypothalamus merangsang proses rembesan
hormon melalui kelenjar pituitari (pituitary
gland).
• Pituitary gland:
– terletak di bawah hypothalamus – mengawal dan
menyelia semua aktiviti kelenjar.
– Terdapat 2 bahagian:
• Posterior pituitary
• Anterior pituitary

45. • Posterior pituitary
– Merembeskan hormon yang mengawal selia
proses penyerapan semula air oleh buah pinggang
– Bagi wanita pula, penghasilan susu
• Anterior pituitary
– Merembeskan hormon yang mengawal selia lain-
lain aktiviti kelenjar seperti:
• ACTH merangsang adrenal cortex menyebabkan
penghasilan cortisone, cortisone pula memberi kesan
kepada tubuh badan

46. Endocrine
Glands
Hormone Produced Function
Pituitary
Gland
Antidiuretic hormone (vasopressin) Its primary function is to help
the kidneys to retain water in the body.
Corticotropin
(ACTH)
These hormones are there for regulating the
hormones of the adrenal glands.
Human growth
hormone
As the name suggests, it is associated with the
growth and development of the body. It is also
known to encourage the production of protein.
Oxytocin Helps contraction of the uterus muscles and
mammary ducts in the breast.
Prolactin The process of milk production in the mammary
glands is carried out by this hormone.
Thyroid-stimulating
hormone
Again, as the name suggests, this hormone is
responsible for the functions of the hormones of the
thyroid gland.

47. Endocrine
Glands
Hormone Produced Function
Thyroid
gland
Thyroid hormone The body's metabolic rate is controlled by this
hormone.
Calcitonin It regulates calcium balance in species other than
humans. Studies are still in progress to find its
function in the human species.
Read more at
Pancreas Glucagon The blood sugar level raises with its help.
Insulin It helps in lowering the blood sugar level. Apart from
this, metabolism of sugar, protein, and fat are also
carried out with its help.

48. Endocrine
Glands
Hormone Produced Function
Adrenal
glands
Aldosterone Responsible for maintaining the salt and water
balance in the body.
Cortisol The functions which regulate the blood sugar level,
blood pressure, and muscle strength in the body is
controlled by the cortisol.
Dehydroepiandrost
erone (DHEA)
It is related to the immune system, bones growth and
also to the mood of an individual.
Epinephrine and
norepinephrine
The nervous system is associated with it.

49. Endocrine
Glands
Hormone Produced Function
Hypothala
mus
Hormone-releasing
hormone (GHRH)
It is known as the growth hormone.
Somatostatin It works by regulating the endocrine system.
Dopamine It inhibits the release of prolactin from the anterior
lobe of the pituitary gland.

50. Endocrine
Glands
Hormone Produced Function
Parathyroi
d glands
Parathyroid hormone Calcium and phosphorus are eliminated from
the body with the help of this hormone, which
is also responsible for bone formation.
Pineal
gland
Melatonin Maintains the body's circadian rhythm, apart
from what has been mentioned in the earlier
segment.
Ovaries Ovaries Estrogen The female sexual characteristics and the
function of the reproductive system are
influenced by the secretion of this hormone.
Progesterone
It plays vital roles in pregnancy. For instance, it
helps in preparing the lining of the uterus for
the fertilized egg to get implanted.
Testes Testosterone Men's sexual characteristics and the nature of
the reproductive system, involve the secretion
of this hormone.