Human+Biological+Science+Stage+3

**Scope and Sequence 2012**

 * || === ** UNIT 3A ** ===

|| === ** UNIT 3B ** ===

** Future of humans **
||  ||
 * **// Human form and function //** ||
 * ** Cells, metabolism and regulation ** || Cellular activities are controlled by feedback mechanisms for the maintenance of homeostasis of body temperature, body fluid composition, blood sugar, gas concentrations and blood pressure. Disruption to homeostasis causes dysfunction that can be controlled by physiological and behavioural mechanisms, and medical intervention.

Cellular activities:
 * role of cell membrane structure and function in active transport and as a receptor
 * DNA controls the production of cellular materials.

Homeostasis by feedback systems: § body temperature § body fluid composition including the role of the nephron § blood sugar § gas concentrations § blood pressure
 * components of a stimulus-response feedback model
 * homeostatic mechanisms that control
 * physiological and behavioural mechanisms that influence the maintenance of homeostasis of the above conditions.

Disruption of homeostasis: § hormonal including diabetes § behavioural including drugs, exercise and diet § disease including thyroid dysfunction
 * causes of disruption
 * treatments for disruption of homeostasis. || DNA codes for the production of proteins in cells via a series of processes. Humans have specific resistance mechanisms, in response to an invasion by pathogens.

DNA and RNA is involved in:
 * protein synthesis (including transcription and translation)
 * cellular control of gene expression including regulator and promoter genes.

Specific resistance:
 * role of B cells, T cells, memory cells and plasma cells
 * antibody and cell-mediated defence
 * primary and secondary immune response
 * passive and active immunity
 * natural and artificial immunity
 * role of antibiotics and antivirals. ||
 * ** Body systems ** || The endocrine and autonomic nervous systems worktogether to control the interaction of body systems to maintain homeostasis in a changing external environment.
 * ** Body systems ** || The endocrine and autonomic nervous systems worktogether to control the interaction of body systems to maintain homeostasis in a changing external environment.

Endocrine system: § regulation of metabolism § regulation of blood sugar § regulation of body fluid composition § lipid soluble—steroid hormones § water soluble—amine hormones.
 * types and location of endocrine glands including pituitary, thyroid, parathyroid, pancreas, adrenal glands, gonads
 * relationship between the hypothalamus and pituitary
 * production site, target organ and effect of hormones associated with the specified glands
 * feedback loops involving endocrine activity
 * hormonal modes of action—cell recognition

Autonomic nervous system:
 * overview of divisions of the nervous system
 * relationship of the Autonomic NS to the body’s nervous system
 * divisions of the Autonomic NS and their effect on various body organs.

Comparison of hormones and nerves in terms of:
 * speed, duration, transmission and specificity. || The nervous system and the musculo-skeletal system interact to provide coordinated actions of the body. Advances in medical technologies can enhance body functions and replace structures to alter the natural course of human development and aid recovery after trauma.

Central and peripheral nervous system:
 * brain (cerebrum, cerebellum, meninges, medulla oblongata, hypothalamus), spinal cord
 * afferent and efferent systems
 * structure of motor, sensory and inter-neurons
 * the reflex arc including components and their functions in the transmission of messages
 * transmission of nerve impulses—generation and propagation
 * control of movement and balance—areas and types of motor control of the body in the cerebrum and cerebellum
 * innervation of muscular contraction.

Muscles—structure and function related to:
 * macroscopic including the types (voluntary, involuntary) and movements
 * microscopic including myofibrils
 * molecular including actin and myosin
 * sliding filament theory of contraction.

Skeleton—structure and function related to:
 * macro and microscopic structure of bone and cartilage
 * structure and functionality of major joint types including ball and socket, hinge, pivot, gliding, immovable, cartilaginous.

Effects of ageing on the nervous and musculo-skeletal systems: Medical technologies used to treat effects of ageing and trauma on the nervous and musculo-skeletal systems:
 * Alzheimer's disease
 * Parkinson's disease
 * osteoporosis
 * osteoarthritis.
 * tissue regeneration
 * stem cell therapy
 * artificial replacements. ||
 * **// Human diversity and change //** ||
 * ** Inheritance ** || Variations in characteristics can arise from gene expression or be the result of polygenes.

§ mechanisms including histone modification and DNA methylation/acetylation § case studies including twin studies.
 * the effect of the environment on gene expression including effect of UV light exposure on melanin production
 * epigenetics
 * polygenic inheritance including human skin colour. || Biotechnological techniques are being developed and used for a range of applications including identification of hereditary diseases.

§ DNA sequencing § profiling techniques § PCR (polymerase chain reaction) § genetic probes
 * techniques including definition, process and examples of use
 * production of human proteins, hormones and vaccines by DNA recombinant techniques including restriction and ligase enzymes
 * treatment of genetic disorders by gene therapy
 * cell replacement therapy and tissue engineering by the cloning of stem cells. ||
 * ** Variation and evolution ** || Gene pools are affected by evolutionary mechanisms including natural selection and chance occurrences. The main evidence for evolution comes from comparative studies in anatomy and biochemistry, and the fossil record.

Gene pools: § mutation § natural selection § random genetic drift including the founder effect § migration § barriers to gene flow § incidence of genetic diseases in various populations including Tay-Sachs disease and sickle-cell anaemia.
 * changes in allele frequencies due to:

Speciation:
 * theory of evolution by natural selection.

Evidence for evolution: § DNA § protein sequences § anatomy including embryology, homologous structures and vestigial organs § fossil formation § geological dating and its limitations § relative dating including stratigraphy, index fossils and fluorine dating § absolute dating including C–14 dating
 * comparative studies:
 * the fossil record:
 * awareness of problems with the fossil record. || Within the classification system, primate and hominin groups show evolutionary trends. Human evolution is the result of interaction of evolutionary mechanisms and the environment.

Primate evolutionary trends:
 * relative size of cerebral cortex
 * olfactory/optical shift
 * gestation time and parental care
 * mobility of the digits
 * teeth shape and dental arrangements.

Hominin evolutionary trends:
 * bipedalism—feet adaptations, hip and knee joints
 * relative size of cerebral cortex
 * prognathism and dentition
 * spine and pelvis shape.

Interaction of evolutionary mechanisms and the environment:
 * effects of environment on early hominin evolution
 * significant cultural advances associated with australopithecines, //Homo habilis, Homo erectus//, //Homo sapien neanderthalensis//, and //Homo sapien sapiens// including tool cultures and the change in lifestyles up to and including the development of agriculture. || ||  ||   ||   ||