HUMAN GROWTH AND DEVELOPMENT STAGES: JS2
CONTENT OUTLINE: Basic Science J S 2
- What is growth?
- What is development?
- Differences between growth and development
- Major Indices of Growth Changes in Living Things
HUMAN GROWTH AND DEVELOPMENT STAGES: JS2
What is growth?
HUMAN GROWTH AND DEVELOPMENT STAGES: JS2:
Growth generally can be define or refers to an irreversible increase in size, quantity, or complexity over time. It can apply to various aspects of life, including physical growth (such as the growth of living organisms), economic growth (an increase in a country’s production of goods and services over time), personal growth (development and improvement of skills, knowledge, and character), and organizational growth (expansion and development of businesses or institutions).
Growth can be measured and analyzed in different ways depending on the context in which it occurs.
What is development?
Development refers to the process by which an organism grows and matures from a single cell into a complex multicellular organism with specialized cells and tissues.
This process involves a series of coordinated events, including cell division, differentiation, and morphogenesis, which give rise to the diverse structures and functions observed in living organisms.
HUMAN GROWTH AND DEVELOPMENT STAGES: JS2:
Developmental Stages Of Human
- Embryonic Development: This stage begins with fertilization, where a sperm cell fertilizes an egg cell, forming a zygote. The zygote undergoes rapid cell division (cleavage) to form a hollow ball of cells called a blastula. Subsequent processes, such as gastrulation and organogenesis, lead to the formation of germ layers and the development of organ rudiments.
- Fetal Development: In organisms that undergo internal development, such as mammals, embryonic development is followed by fetal development. During this stage, organ systems continue to develop and mature, and the organism grows in size and complexity within the protective environment of the uterus.
- Postnatal Development: After birth (or hatching in some organisms), further growth and maturation occur as the organism adapts to its environment. This includes physical growth, neurological development, and the acquisition of behaviors and skills necessary for survival.
- Metamorphosis: In some organisms, such as insects and amphibians, development involves distinct stages with significant changes in body form and function. Metamorphosis is the process by which larvae undergo dramatic structural and physiological transformations to become adults.
Differences Between Growth and Development
While growth and development are related concepts, there are key differences between the two:
- Definition:
- Growth: Growth refers to an increase in size, quantity, or complexity over time. It typically involves measurable changes, such as an increase in height, weight, or the number of cells.
- Development: Development is a broader concept that encompasses progress, advancement, or improvement in various aspects of life. It involves qualitative changes in structure, function, and behavior, leading to maturity or higher levels of organization.
- Nature:
- Growth: Growth is primarily a physical phenomenon, involving quantitative changes in size or number.
- Development: Development encompasses physical, cognitive, emotional, and social aspects, involving qualitative changes in structure, function, and behavior.
- Timeframe:
- Growth: Growth typically refers to changes that occur over a relatively short period, often involving measurable increases in size or quantity.
- Development: Development is a more long-term process, involving progressive changes over time that lead to maturity or higher levels of organization.
- Measurement:
- Growth: Growth is often measured quantitatively using metrics such as height, weight, or cell count.
- Development: Development is assessed qualitatively based on changes in structure, function, behavior, or other observable characteristics.
- Examples:
- Growth: Examples of growth include an increase in the height of a plant, the weight of an animal, or the number of cells in a population.
- Development: Examples of development include the acquisition of new skills, the maturation of organ systems, or the progression from infancy to adulthood in humans.
Growth primarily refers to quantitative changes in size or quantity, while development encompasses qualitative changes in structure, function, and behavior across various aspects of life. Growth is a component of development but does not fully capture the complex processes involved in overall development.
INDICES OF GROWTH CHANGES IN LIVING THINGS
The major indices of growth changes in living things can vary depending on the organism in question and the specific context of growth being considered. However, some common indices of growth changes in living things include:
- Physical Size: Increase in physical dimensions such as height, length, width, or volume. This is often a visible and easily measurable indicator of growth in multicellular organisms.
- Weight or Mass: Increase in body mass or weight, reflecting the accumulation of cellular material, tissues, or other organic matter.
- Cell Number: Growth in multicellular organisms often involves an increase in the number of cells through processes like cell division (mitosis).
- Cell Size: Growth can also occur through an increase in the size of individual cells, known as hypertrophy, which involves the enlargement of cells rather than an increase in their number.
- Organ or Tissue Growth: Growth may involve the development and enlargement of specific organs or tissues, such as the growth of leaves in plants, the development of limbs in animals, or the expansion of specific organs like the brain or liver.
- Biomass Accumulation: Growth can be quantified by measuring the increase in total biomass, which includes all organic material produced by an organism.
- Metabolic Rate: Growth is often accompanied by an increase in metabolic rate, reflecting the higher energy demands associated with growth processes.
- Reproductive Capacity: Growth often involves the development of reproductive structures and an increase in reproductive capacity, enabling the organism to produce offspring.
- Developmental Milestones: Growth in organisms with complex life cycles may be marked by the achievement of specific developmental milestones, such as the emergence of leaves in plants, the development of limbs and sensory organs in animals, or the attainment of sexual maturity.
- Sex: Sex also play a very important factor which influences human growth and development. There is lot of difference in growth and development between girls and boys. Physical growth of girls in teens is faster than boys. Overall the body structure and growth of girls are different from boys.
- Developmental Stages: Growth is often characterized by distinct developmental stages, each associated with specific changes in morphology, physiology, and behavior. These stages may include embryonic development, larval stages (in organisms with indirect development), and adult stages.
Assessment/ Evaluation
- What is growth?
- What is an instrument used to measure growth in animals?
- Differentiate between growth and development
- What is the instrument to measure growth in plant?
- Differences between growth in plants and animals