Heredity refers to the process of transmitting genetic characteristics from parents to offspring. Physical traits and even physical defects are known to be hereditary. Also, some mental traits and mental defects are known to be hereditary. (http://www. slideshare. net/GenPsyche/biological-bases) Nature and Nurture Both nature and nurture affects all aspects of human behaviour. “Nature refers to all the evolutionary factors that have shaped the genetics that we have inherited from our parents and ancestors. Nurture refers to all the things that have influenced us since we began to develop (from the moment we were conceived).
Nature determines the range of our human potential. Nurture affects the ways that our human potential is actualized, being helped or hindered by good or bad environmental inputs. ” (http://www. soc. ucsb. edu/faculty/baldwin/classes/soc142/n&n. html) In the debate versus nature and nurture, nature refers to an individual’s qualities that are inherited; for example nativism. Biological and family factors affect one’s nature. Nurture refers to personal experiences; for example, empiricism or behaviourism. Social and environmental factors affect one’s nurture. (http://www. diffen. com/difference/Nature_vs_Nurture) Genes
According to Mcgraw-Hill, “Genes, the units of hereditary information, are short segments of chromosomes. Genes combine with other genes to determine our characteristics. There are dominant and recessive genes. Polygenic inheritance is the effect that multiple genes have on behaviors and mental processes. The study of genetics has progressed from the basic experiments of Mendel to molecular genetics and the development of genomes. Genetic methods include selective breeding and behaviour genetics. ” (http://highered. mcgraw-hill. com/sites/0072937769/student_view0/chapter3/) NEUROLOGICAL FOUNDATIONS Nervous Systems (http://www. mc. maricopa. edu/faculty/farabee/BIOBK/BioBookNERV. html#Nervous Systems) The nervous system is the body’s decision and communication center. “Multicellular animals must monitor and maintain a constant internal environment as well as monitor and respond to an external environment. In many animals, these two functions are coordinated by two integrated and coordinated organ systems: the nervous system and the endocrine system. ”
There are three basic functions performed by nervous system, and they are: receive sensory input from internal and external environments, integrate the input and respond to stimuli. . Brain The brain is made of three main parts: the forebrain, midbrain, and hindbrain. The forebrain consists of the cerebrum, thalamus, and hypothalamus (part of the limbic system). The midbrain consists of the tectum and tegmentum. The hindbrain is made of the cerebellum, pons and medulla. Often the midbrain, pons, and medulla are referred to together as the brainstem. (http://serendip. brynmawr. edu/bb/kinser/Structure1. html) Vertebrate evolutionary trends include (http://www. emc. maricopa. edu/faculty/farabee/BIOBK/BioBookNERV. html#The Brain) 1. Increase in brain size relative to body size. 2.
Subdivision and increasing specialization of the forebrain, midbrain, and hindbrain. 3. Growth in relative size of the forebrain, especially the cerebrum, which is associated with increasingly complex behaviour in mammals. b. Spinal (http://www. emc. maricopa. edu/faculty/farabee/BIOBK/BioBookNERV. html#The Spinal Cord) “The spinal cord runs along the dorsal side of the body and links the brain to the rest of the body. Vertebrates have their spinal cords encased in a series of (usually) bony vertebrae that comprise the vertebral column. The gray matter of the spinal cord consists mostly of cell bodies and dendrites.
The surrounding white matter is made up of bundles of interneuronal axons (tracts). Some tracts are ascending (carrying messages to the brain), others are descending (carrying messages from the brain). The spinal cord is also involved in reflexes that do not immediately involve the brain. ” Peripheral Nervous System (http://psychology. about. com/od/pindex/f/peripheral-nervous-system. htm) The Periperal Nervous System (PNS) is the division of the nervous system that contains nerves which lie outsite the Central Nervous System (CNS). PNS’s primary role is to connect CNS to the organs, limbs, and skin.
PNS is divided into two parts, somatic nervous system and autonomic nervous system. “The somatic nervous system derives its name from the Greek word soma, which means “body. ” The somatic system is responsible for transmitting sensory information as well as for voluntary movement. This system contains two major types of neurons: sensory neurons (or afferent neurons) that carry information from the nerves to the central nervous system, and motor neurons (or efferent neurons) that carry information from the brain and spinal cord to muscle fibers throughout the body. While the Autonomic Nervous System is responsible for regulating involuntary body functions, such as bloody flow, heartbeat, digestion and breathing. “This system is further divided into two branches: the sympathetic system regulates the flight-or-fight responses, while the parasympathetic system helps maintain normal body functions and conserves physical resources. ”