Concept of Human Growth & Development (Very Important)
Anthropologist have always been interested in variations in human species with respect to socio cultural elements, biological and also geographical dimensions
Growth and development during different phases of live cycle like prenatal development ,infancy ,childhood ,adolescence and senescence is of the prime concern for physical anthropologist to study individual populations or in co-relation with others
Growth is an progressive development of an individual or an body part from its earlier stage to maturity. It is mainly studied as a quantitative increase in the size of the body or its parts it is included within the larger term development
Growth is part of development → Growth is the Quantitative Development
Cellular process responsible for growth can be
Hyperplasia - when cells gets multiple, no. of cell increasing as a result of cell division involving replication of DNA leading to formation of functional identical cells
Hypertrophy - When the size of cell is getting increase due to increase in its functional units particularly proteins
Accretion - increase in the intercellular substances of both organic and inorganic nature, Distance between cells increase. Proteins and lipids are organic substance present b/n the cells. Inorganic is minerals
Development →it refers to progressional changes of both qualitative and quantitative nature were undifferentiated immature cells(pluripotent steam cells are getting transformed through differentiation into different types of cells which are specialised
The quantitative elements of development is growth only but the qualitative changes can include functional maturity and come differentiation
Growth does not continue through out the live and generally stops after attaining maturity were as development is progressive and continues throughout the life. Later the term development was extended to include social maturity as well as behavioural changes. GOSS who elaborated the qualitative and quantitative elements of development
Principles of Growth and Development (Can be studied from Physical Notes)
Chronological and Biological Age
Chronological age is the age of an individual as the no. of ages after the birth. i.e the actual no. of yrs a person have lived in years, months, days etc
Biological age on the other hand represents the biological status of maturity referring to how old a person seems to be. it is an individual’s development based on biomarkers at molecular, cellular or tissue levels
Biological age is also termed as physiological age. It is governed by genetic factors/hereditary factors/lifestyle and the geographical conditions of the habitat. A person can be having 50 as the chronological age but physiologically the body can be matching with 40 yrs. of the chronological age
Somatotyping*** ( Can be Studied from Physical Notes)
Introduction
Somatotype-term was coined by American physicist Sheldon
Somatotype is a quantified expression and scientific description of the present morphological conformation or physique of a person.
And the process of defining, appraising and explaining the somatotype is somatotyping
Somatotypical studies have contributed in better understanding of diversity of human builds can be applied to specific diseases and disorders like austrioporisis, scientific studying of ageing, diet plan and nutritional requirements for individuals, exercise programs for athletes to achieve their full potential
Along with genetic factors environmental factors, nutrition also defines the somatotype.
Viola’s Method of Somatotyping
He was an Italian physician
Proposed classification of somatotypes based on physique through photoscopic studies and latter used some anthropometric measurements
he differentiated 4 different types of somatotypes
Longitype
Longitype - longer limbs relative to the trunk volume, larger thorax relative to abdomen and large transverse diameter relative to anterior and posterior
Brachitype
Brachitype - is opposite of longitype short limbs related to trunk, less transverse diameter relative to anterior posterior and shorter thorax relative to abdomen. Massive and robust bodies
Normotype
Normotype - a proportional size of limbs and truck, thorax and abdomen and transverse with the anterior posterior diameters (they are b/w Longitypes and Brachitypes)
Mixed
Mixed - disproportional body size ,non uniformity physique, the above indices fail to reach upto a conclusion ,not very much common
Sheldon’s Method of Somatotyping
Introduction to Sheldons Method
Book-‘Varieties of human physique’
Sheldon defined somatotype as quantification of 3 primary components determining the morphological characters of an individual expressed as a series of 3 numerals
1st is endomorphy, 2nd is mesomorph, 3rd is ectomorph
Each component of the physique is assessed individually on a 7 point scale with one as the least expression(minimum), 4 as the moderate and 7 as the hight /full expression(maximum)
The rating of each component determines the somatotype which is expressed by the 3 numerals for which the sum is minimum 9 or maximally 12
The conceptual approach of Sheldon’s method is based on the premise that continuous variations occur in the distribution of physique and thus a variation is related to differential contribution of 3 specific components i.e endo ,meso or ecto morphs.
Sheldon studied somatotyping by dividing the body into different
components like
Maximum individuals are a mixed of these 3 somatotypes so the somatotype rating cannot be that much absolute
Criticism of Sheldons Method
Sheldon’s concept of somatotype was based on white men of America that too of limited age group so it was criticised for being less representative
Sheldon stated that 1 to 7 should be the range of somatotype rating which is not elaborative also unnecessary and unjustified restrictions of total of the components b/n 9 to 12 was of no practical application. Impact on environment of human physique was ignored
Muscular growth and fatty deposits were not explained specifically to the most prominent muscles like triceps, traf muscle etc
Heath and Carter Method
Theoretically A combined approach of anthropometry and photocopy was used for estimation of somatotype but in practice heat and cater method is primarily anthropometric in nature as over emphasis on photocopy is time consuming, costly and not very much efficient
The Method developed against the response for Sheldon’s Method
Heat and Carter criticised the Sheldon’s method for accommodating a narrower range of rating ,Arbitrarily for 7 point scale and also by eliminating the unjustified sum of components b/n 9 to 12
Under this method data was collected for somatotype rating based on Height Weight ratios HWR ,Heat and cater studied both male and Female, Somatotype
The anthropometric measurement used by heat and cater are more objective and in the direction to standardised somatotypes and is way more efficient than focusing on photocopy
The Somatotype components and dimensions used in this are different from Sheldon’s Method
Advantages of heat and cater method are related to its objectivity, scientific measurements applicable to both males and females and more focus is on studying the present somatotype of an individual
Methods for Studying Growth
Two prominent methods used to study the growth
Longitudinal Method
The same subject or group of subject is studied and measured repeatedly year after year
Here individual rates of growth and timings of specific development can be
easily analysed through the data collected
Both the aspects can be studied like
the individuals rate of growth
the timings of specific development events
Data related to growth on an individual from birth to the maturity may take up to 20 years to completed with the help of this method
So, the principal drawback of comprehensive longitudinal study is time taking and relatively small no. of individual /subjects can be studied. also, it is very costly and dependent upon the continuous corporation of the subject as well as the enthusiasm of researcher
It is thus essential that the highest levels of accuracy to be maintained in collecting and recording the data so that maximum results can be achieved
Cross - Sectional Method
Here the subjects are studied only once in a way that subjects of the different ages are studied at a particular time like some at early infancy, some at early childhood, some at adolescence and some adult individuals became a part of the sample
Cross sectional method provides a general description of age-related growth changes. the biggest advantage is growth studies can be completed within the shorter period of time
In a comparative survey of children in different populations more focus is on the average outcomes i.e the mean and the variations in growth patterns b/n different children’s
The biggest shortcoming of this method – is individuals’ growth and development on year-to-year basis cannot be deciphered
To overcome the shortcomings of these two methods sequential study methods can be adopted combining the two approaches in a way that individuals from the cross-sectional samples are tested more than once and the result is analysed to understand the differences and similarities. This method seems to provide more realistic assessment than cross sectional/longitudinal methods
Patterns of Human Growth & Growth Curve
Distance & Velocity Curve
Measure of an individual taken at specific intervals and plotted against time can provide graph of progress for total amount of growth achieved
Distance Curve
Call grand which measurements are plotted against Time related to actual height of individual is call Distance Curve
It tells us things like
height achieved for particular age is reflected
how far child has reached towards adulthood
Distance Curve represnets amount of growth achieved at given moment or at successive time periods
Velocity Curve
Veocity curve represents variation in rate of growth with time is velocity curve. It is not defining actual height of an individual at specific age. What is defining rate of growth with time
Conclusion
British natural Scientist & mathematical biologist, Sir Darcy Thompson, in his book on growth and form explained concepts of distance and velocity curve.
He considered distance curve as “continuous succession of varying magnitude”
He defined velocity curve as rate of change of height with time and called “rate of cahnge of varying velocities”
Phases of Growth Curve
Rapid Growth during Infancy and Childhood
Steady and COnstant growth during Middle Childhood
Rapud Growth during adolescence
very slow growth as Individual appraoches adulthood
Types of Growth Curve based on Body Systems
General Curve
It describes growth of body as a whole and most of body systems, respiratory digestive, urinary and circulatory system, general car which distance covered and graphs that is
Rapid Growth - INfancy and Very Early Childhood
Steady and Constatn Growth - Middle Childhood
Increase in Growth - Late Childhood
Rapid Growth - Adolescence
Slow and Eventual Succession of Growth - In Attainment of Adulthood
Neural Curve
Characterise growth of brain, nervous system, parts of skull and even eyes, nervous tissues, experience, rapid growth in early postnatal life and greater than 95% of total increment in size of brain is attained by age of seven years
Seven year of each. Tissues shows steady gain with slightly extra growth in adolescence.
Reproductive Curve
illustrates growth & pattern of primary & secondary sexual characteristics in males and females including growth of
Ovaries and Uterus - Primary in Females
Testes and Seminal Vesicel - Primary in Male
Develeopment of Breasts - Secondary in Female
Development of Larynx & Moustache - Secondary in Female
Growth of Pubic Hair in both Male and Female
These tissue shows
slight growth in infancy
latent period during childhood
rapid growth in maturation during adolescence
Lymphoid Curve
It is Development Curve of Lymphatic System ( Lymph Nodes etc)
X Axis - Size Attained in % of Full Maturity in Post Natal Growth
Y Axis - Years
Lymphatic system including thymus tonsils, spleen and lymph nodes acts as a secondary circulatory system for tissue fluid is helping in development of immune response
Lymph Node curve demonstrates rapid growth, until early adolescent years, even more than 100% capacity, later it declines most probably as a result of activities of sex hormones during puberty
Stages of Human Growt
Introduction
Human Lufe Cytle starts with Fetilisation of Sperm and Egg, thus forming Zygote. then the embryonic and pre natal grwoth and development followed by birth and post natal development
Fertilisation
Fusion of Male and Female Gamets
Pre Natal Stage
Begins with Conception
Involves Fomration of Zygote / Embryo
There are Stages in Pre Natal Stage
Embryonic Stage - Conception to 8th Week of Pregnancy
Cells of Embryo starts dividing
Embryo moves from Fallopian tube towards womb
3rd & 4th Week
Embryo is attached with Uterus (womb) wall by 3rd ot 4th week of pregnancy
5th Week
By 5th week division of Brain, Spinal Cord and Heart occurs
Within this week
Hear Starts Beating
Heart becomes Cearly visible in Ultrasound
6th Week
Heart
Starts Pumping embryos own blood to his her own brain and body parts
all 4 chambers of heart are present
By End of this phase 1 Million heart beats have occurred
6 Week Embryo measures less than an Inch but still formation of arms and legs have started
Early Foetal Stage - 9th to 24th Week of Preganncy
Here, Movement of Hands, Neck and Hiccups begin
Heart is Nearly Fully Formed
Girls have ovaries and boys have testes
After 10 weeks developing human called foetus or unborn offspring
Kidneys begin to produce and release urine
Fingers and toes are fully formed and free
Around 17th week, blood cell formations starts in the form of bone marrow
Foetus starts to store energy in form of fats
By 18th week formation of breathing passage is complete
By 22nd week sense of hearing begins to dunction
Foetus starts responding to sounds
Between 20/23 weeks - rapid eye movement begins
By end of 24th week > 30 million heartbeats have occured
Late Foetal Stage - 24th week of pregnancy to birth
By 26th week sudden and loud noises may trigger response in developing foetus like it may increase body movement, heart rate
By 29th week, pupils of eye react to light
By 37th week foetus has a firm hand grip
Heart has beaten > 50 million times by now
around 38 weeks - weight of foetus > 6 pound measuring around roughly 19 niches for head to head at birth new born baby typically weighs between 6 to 8 pounds
and heigh is around
Birth Post Natal Development
Introduction
28 Days after birth, marks the growth and development of newly born in extra urine environment
Babies maintain a temperature within a very narrow liit
inadequate growth and development during prenatal period, disposes newborn to vulnerability specially for duration of first 28 days after birth and is pioneering factor contributing to high neo natal fatality
Phases of Post Natal Growth
Infancy / Infanthood ( After Birth 4 Weeks / 1 Month / 28 Days )
It is the period during which nursing takes places ,typically lasting for 3 to 4 years of the age ,getting started after 28 days of the birth
A normal healthy baby doubles its’ birth weight in the 1st 6 months and triples within a year, during this period there is a great expansion of head and the chest. Thus permitting development of heart, lungs and brain the most vital organs for survival
The bones which are relatively soft at birth begin to harden with the process of ossification and deposition of calcium
Calcification of posterior and anterior fontanels begin during this period
Brain weight increases rapidly during infancy and by the end of 2nd year the brain has already reached 75% of its adult weight. Human brain grows more rapidly during infancy then any other tissue organ of the body
The gradual attainment of control over head ,upper trunk and upper extremities is allied with accomplishment of sitting posture and proficiency in walking skills during infant hood
The fatal posture of inverted position will be converted into holding the chin up within 1st two months of the birth and child is able to hold the chest up within two to three months of the birth
Sits when supported in the 1st 4 months
Sits w/o support in the 1st 6 to 7 months
Stands w/o the support in the 1st 9 months
Crawls in the 1st 10 months
Walks if supported in 10 to 11 months
Stands alone w/o support in 11 to 12 months
Walks alone w/o any support in 12 to 14 months
Emergence of milk teeth allows the infants to switch from breast feeding to eating appropriate required food
Deciduous (milk) teeth emerge one month earlier in boys w.r.t girls and in all other aspects of physical growth and maturation girls are on an average of ahead of boys
Childhood - Early, Middle & Late
Early Childhood → 4 to 6 Years
The rate of growth slows downs, dentition is immature
Digestive system is small and not fully developed so specially prepared food is required in this stage. The neurological development along with motor skills are being developed in this phase
Leaning abilities became faster for both skills as well as sociocultural commands and elements like bowing the head Infront of a religious place
cultural elements like adoption of language by comprehending the words is one of the significant development in early childhood
Middle Childhood → 6 to 8/9 Years
This Stage of human growth and development. Is suppose to be most stable one w/o much changes observable changes in body height and weight
Neurological, Psychological & Motor Skills continue to develop. The physical growth is proceeded towards 2 direction’s mainly
The Walking Pattern / Locomotion starts matching with the adults and replacement of milk teeth with permanent teeth is almost complete with the exception of second molar
Late Childhood → 9 to 11/12 Years
Also termed as Pre Pubertal Stage
Sexual dimorphism is emerged in this stage
It is included by sex hormone, linear growth of the body will take place, sexual dimorphism can be witnessed i.e different looks for boys and girls
Children will start getting better writing and reading skills/speech skills and these are signs of a dependent child becoming independent for day to day activities
Adolescence / Puberty
The pubertal stages or the adolescent experienced the changes at a faster rate as compared to any other stage. This can be considered starting with onset of puberty when sex hormones are getting produced and is the physical transformation of a child towards adolescent and adulthood
No. of biological changes take place during adolescent
like sexual maturation
increase in height and weight
completion of skeletal growth with increase in skeletal mass
changes in body composition wrt hormones
protein deposition and fatty deposits
Onset of puberty is generally 2 years earlier in girls than boys
Average Age for girls is 11.5 to 13.5 yrs
Average Age for boys it is 13 to 15 years
Secondary Sexual Characteristics are expressed in both boys and girls like breast dev
Girls - onset of menstruation (menarche-beginning of menstruation, menopause-end of menstruation)
Girls & Boys - growth of body hair
Boys - genital development in boys etc
Case Study 1 : A.M Tripathi in his study of age of menarche of girls of various Indian state found that lowest age is their in girls of
Delhi 11.2
followed by Calcutta 12.2 to 12.7 yrs
UP 12.8 to 13.3 years
highest age of menarche was found in Gujarat, nearly 14.5 to 14.8 yrs
Case Study 2 : In a study by Kant Et Al it was found that puberty appears to set in early among the Indian boys but full maturation seems to take longer time than the boys of western countries
They studied boys in central part of India. Within india the avg age of development of puberty in boys is nearly 14 yrs but is found late in tribal boys
So the onset of puberty in both boys and girls and age of menarche in girls is not only governed by biological or physiological factors but also influenced by multiple other factors like-environmental and climatic factors ,socio economic status ,nutritional status . the upbringing environment stress ,intoxication ,pollution etc
Adulthood
Adulthood and maturity is the time of peak physical maturity, starts getting achieved after the completion of teen ages ,full physical strength of the body is achieved in late 20’s and early 30’s. Attainment of adult stature, sexual maturation are indications of transitions from adolescence to adulthood . increase in the height stops as the long bones of the body like femur lose their capability to increase in length
Most significant child bearing age ,fully mature immune system so there is a resistance to pathological influences
The most striking feature is this resistance to pathological influences only as a stability, a homeostasis (stable condition ,constant internal env.) is achieved
Maturity or adulthood is having one of the most significant activity related to cellular functioning. Full strength of the bones getting achieved and healthy sperms and eggs for procreation
Ageing & Senescence
Background
Senescence : the condition or process of deterioration with age
Biological Basis of Senescence : Divisional Maturity of Cells is reached and Achieved
Ageing : Ageing is the process of becoming older
Introduction
Also Termed as Declining Stage or Negative Growth Stage.
Senescence Includes all those manifestations in structure and function of various organs of the body which decline or deteriorate during later periods of life
Ageing → In Humans takes form of morphological and functional impacts as a progressive and irreversible change.
Senescence & Ageing Leads to Gradual Decline in
Body Physiology, Metabolism and Activities of Individual →
All the Individuals follow the same human cycle of Birth, Growth, ReproductiveMaturity, Senescence and Death
Three Theories of Senescence
Various Theories have been Proposed related to ageing and senescence which can be classified in Three Broad Categories
Summary Cellular Theories
Background
Ageing due to Intra Cellular Process
Errors in Biochemistry of cells
Theories
Theory of Hayflick Limit - Leonard Hayflick
Running Notes
Lungs - Fibroblasts - Divide - But Division is Limited - i.e Division is not Fully Functional throughout Life
Hence he got an Idea that like Lung Cells → all Cells in the Body have a Divisin Limit
As Age of Individual Increases - Cell Division Capacity of a Person (will reach a Particular Limit) & at a Point of time
Division of Cell = Multiplication of DNA content
Full Division Capacity will be Reached (Hayflick Limit)
When Hayflick Limit is Reached Cells will not be able to divide the Nucleus and hence Cell will not Replace with New Cells and this will lead to Ageing
Dictation
Hayflick Reported that Fibrblastas of Human Lungs divide like Other Cells of the Body but their Division is Limited like the Same way various cells of the Body will have a capacity to divide for a Limited Number of Times which is achived at a Specified Age
Senescene and Ageing is the Result of Loss of Cell Functioning due to “its capacity to divide further is lost”.
When cells reach their maximum division point there will not be further division of cells as they cannot divide the Nucleus & Genetic Material
This Maxium Capacity of Division in Cell is Hayflick Limit
So after certain age & after acheiving a fixed number of divisions
cells will not divide further
dead cells will not be replaced by new cells
events of ageing and senescene will occur
Theroy of Free Radical Reaction - Becker & Smith
Free Radical
They are continuosly produced in the body during metabolic reaction and if they are not neutralised they damage the cells
Running Notes
FR produced contunuosly in cell
will lead to cell damage → Leads to Death
Neutralised by Anti Oxidants
Presets the Ageing
Will not allow damage to cells before its Hayflick Limit
Here FR of O2 is talked about here. This casues ageing and damage of the cells
Free Radical of Oxygen are getting continuosly produced in the cells leading to damage and death of cells. as the free radicals of oxygen can be transformed easily into super oxide radicals by various enzymatic activities.
Whent this super oxide radical gets combined with water, a Highly Reactive Radical of Hydroperoxyl HO2 is getting formed
HO2 / Hydroperoxyl → will primarily combine with Free Unsaturated Lipids circulating in the cells to form ageing pigment called Lipofuscin
How will this Lead to Death ?
The Free Radicals & Lipfuscin will block the cellular Transport i.e Influx of Nutrients inside the cell and outflux of Toxins, outside the cell
This will Lead to Cell Senescene and Cell Death
Theory of DNA Errors - Hart & Setlove
Errors in DNA Replication are continuosly rectified through proof reading mainly through activity of Enzyme DNA Polymarase 1.
If the Errors of replication remain undetected, it can lead to Mutations i.e healthy DNA will not be Multiplied Further & continuos accumulation of DNA Errors will impair the cell function leading to senescene and death of the cell
Theory of Missing Factors - Dr M S Kanugo
Running Notes
He is a Famous GerontologistT from India
Non Functional Genes of Adulthood - Yes Problem
Non Functional Genes of Young Age - No Problem
Dictation
In the Words of Dr Kanugo,
Ageing is not due to Malfunctioning of Specific Genes of Childhood or Adolescence
but due to non functioning of Genes Responsible for maintaining adulthood and later stages
This Non Functioning could be due to
Internal - Endogenus Factors
Mutation
External - Exogenus Factors
Stress, Pollution, Nutrition, Intoxication
Futher Studies Highlighted that : Reproductive Phase of Life of Individuals deplets certain genes/factors responsible for maintaining adulthood.
These Missing Factors Accelarate Ageings and Senescene
Extra Cellular Theories
Background
Ageing due to Extra Cellular Events
Not Dysfucntioning of Cellular Machinery
Reason is outside the cell
Theories
Immunological Theories - Burnet & Walford
Running Notes
Important for functioning of Immunological System
Spleen
Lymph Nodes
Bone Marrow
Thymus Gland
With time their
Efficiency Decreases
Degeneration Takes Place
Leads to Ageing & Senescence
Dictation
Various Parts of the Immune Response of the body like Spleen, Lymph Nodes, Bone Marrow, Thymus etc continuously loose their efficiency after attainment of adulthood
Efficiency of Thymus Gland is the most significant one and its degeneration and decreased efficiency is contributing towards ageing of the Animal Kingdom (Humans)
Certain Genetic Changes or Mutation can also Trigger Auto Immune Response and hence leading to faster process of ageing and senescence
Collagen Theory - Group of Members
Running Notes
Structure
Three Helix
Forms Super Helix
This Super Helix dominated by Non Covalent Bonds
Process
Less Stable : Will Lead to Opening of Helix
Opening → Division of Cells
With Ageing - Non Covalent Bonds Stabilise and Transform into Covalent Bonds
Collagen Not Divde
Non Healthy Intracellular Activities
Under Nourishment of Cells
Collagen
Collagen is the Most Abundant Protein Present in Animals
Present in Skeletal System and Intracellular Spaces
Bonds
Covalent Bond - formed by Sharing of Electrons - More Stable
Non Covalent Bond - formed by Co Ordinate Bonds - Less Stable
Dictation
Collagen Protein in Animals is made up of 3 different Poly Peptide Chains forming a Super Helix supported by Non Covalent Bonds.
As Age Advances these Polypeptide chains are stabilised by covalent binds and because of this transformation.
This Transformation doesn't allow a :
Healthy Intracellular Environment and
Cellular Transport is Obstructed
leading to
Accumulation of Toxins in the Cells
& Undernourishment of Cells
Causing Senescence and Death
Modern Theories of Senescence
These are Based on Multiple Scientific Research
Background
Mixed Approach
There can be Multiple Reasons which can be Intra Cellular, Extra Cellular & Blend of Intra & Extra Cellular
Theories
Programmed Ageing Theory
Running Notes
It is Pre Programmed in Cells, that after a Particular Stage, Age and Division of Cells, the Cell will stop functioning
Chromosomes 1 & 21 - Have this Programming
When Cell Forms it is Pre Programmed like a Biological Clock
Dictation
Theory Supports the Idea that Pattern of Ageing's and Senescence is Pre Programmed & Pre Determined & is an Inborn Mechanism confined to Chromosome 1 & Chromosome 21
Hence it is almost certain that when a Particular Cell will reach upto stage of Ageing
Wear & Tear Theory
Running Notes
Grow Older
Blah Blah
Dictation
With Age, older cells loose their ability to Repair or Replace the Damaged Components due to Various Internal and External Factors, including mutations, Nutrition, Life Style Etc
Factors Affecting Growth and Development
Genetic Factors
They Control the Growth & Development in All Stages of Human Development
Starting from
Fertilisation of Egg & Sperm to
Embryonic Development to
Post Natal Development
That is throughout the Life Cycle of an Individual
Different Characters Appear at Different Stages of Growth and are controlled by Genes , so to achieve a Co Ordinated Growth Different Genes are needed to be Activated at Specific Time Periods of Life Cycle
Environmental Factors
Climatic Factors
Eskimos - Polar Region
Less Rate of Growth & Development
Negrito - Africa Region
Faster Rate of Growth and Development
Migration of Individuals and Exposure to New Geographical Conditions can alter the Rate of Growth and Development
Socio Economic + Cultural Factors
Availability of
Food & Nourishment
Type of Food
Will detrmine G&D
Cultural Factors
In Cultural Factors the
Home and Hygiene of the Local Community
Acceptance & Non Acceptance to Intoxicants
Practises of Polygamy
Frequent Pregnancies
Will Alter Rate of Growth & Development
In Mothers, Foetus & Kids
Biochemical Factors
Running Notes
Hormones - Most Important Here
G&D is Interplay of Functioning of Hormones
Balance of Hormones Needed in 3 Stages
Pre Natal
HCG
Human Chorionic Gonadotrophin
Released by Placenta
Thyroxine
Post atal
Thyroxine
Growth Hormones
Adolescence
Thyroxine _ Growth Hormone
LH - Lutinising Hormone
Released By : Anterior Pituitary
Different Functioning in Males and Females
Males
Secretion of Testosterone
Trigger Growth & Development
Females
Helps in Ovulation → Menstrual Maturity
Trigger Growth & Development
FSH - Follicle Stimulating Hormone
Stimulates Release of Egg in Females
Dictation
Entire Process of Human Growth & Development in
Pre Natal
Post Natal
Adolescence
is largely a Result of an Interplay between various Hormones playing a Crucial Role in G&D
In Pre Natal G&D
Two Most Important Hormones are : Thyroxine & HCG
HCG
Human Chorionic Gonadotrophin
Released by Placenta
In Post Natal G&D
Two Most Important Hormones are : Thyroxine & Growth Hormone
Thyroxine - by Thyroid Gland
Growth Hormone - by Pituitary Gland
In Adolescent Stages : Thyroxine & Growth Hormones are accompanied by LH & SFH
LH in Males & Females
Luteinising Hormone - Released by Pituitary Gland
Responsible for
Females - Ovulation
Males - Secretion fo Testosterones in
Helps in Development of Secondary Sexual Characters in Males & Females
FSH in Females
Follicle Stimulating Hormones - Released by Pituitary Gland
Responsible for
Secondary Sexual Characters
Secretion of Estrogen
Nutritional Factors
Nutritional Requirements of Individuals may vary based on the
Genetic Factors
Environmental Factors
Physical Activity etc
It is also Variable in Males and Females
Hence, If Nutritional Requirement are not Fulfilled Growth & Development will not be optimal
i.e Malnourishment can lead to
Impairment in Growth
Delayed Growth
Stunting Etc
Other Factors
Secular Trends in Human Growth
Background
Related only to Growth & Not Development
Direction in Which Growth is Going is Secular Trend
Its Uni Directional, cannot be Cyclic or Reversed
Its Uni Directional and Consistent
Types of Secular Trends
Positive
in a Specified Direction
Body Size & Weight Increase
Negative
Reduction in Size Generations after Generations
Age of Maturation Decrease
Neutral
Cession of Trend
Case Studies
R M Malina
Secular Trends in Height of Adults
11 19 Century Negative Secular Trend
After Mid 19th Century - Trend Reversed
A S Rosh
Based on Children
Height of Children at Each Age is showing Positive Secular Trend
Factors : Better Health & Nutrition
Definition
Secular Trend in Human Growth : means Growth Trends on Physical Parameters of Human Body like Height and Weight which follow a Specified Direction and remain consistent over time.
Displayed By Maximum Population and Age Groups.
These Trends are not cyclical or seasonal.
Based on Longitudinal Growth Studies in Different Human Groups from Mid 19th Century, a Secular Trend of Growth has been observed by Anthropologists as well as by nutritionists
