Question

1. List and describe the life cycle stages of humans. Discuss the genetic, hormonal, and environmental factors influencing human growth and development. Describe the pattern of human brain growth. What is the importance of delayed brain growth in humans? What are pleiotropic genes and what do they help us to understand?

Answer 1

Ans-

Ans-1)The stages of life cycle change-there are 9stages of growth and development of human.

1)Prenatal Development-Conception occurs and development begins. All of the major structures of the body are start to forming and the health of the mother is of primary concern.

2)Infancy and Toddlerhood-The first year and a half to two years of life span are the dramatic growth and change. A newborn, with a sense of hearing but very poor vision.toddler transformed into a walking, talking toddler within a relatively short period of time.

3)Early Childhood-Early childhood is also referred as a preschool years consisting of the years which follow toddlerhood and precede formal schooling. As a three to five-year-old, the child is busy learning language, is gaining a sense of self and greater independence, and is beginning to learn about the world.

4)Middle Childhood-

5)Adolescence-Adolescence is a period of physical change in the body.example- overall physical growth spurt and sexual maturation, known as puberty.

6)Early Adulthood-

7)Middle Adulthood-

8)Late Adulthood-This period of the life span has increased in the last 100 years.

9)Death and Dying-

Ans-2) Factors which affect the growth and development-

1) genetical factor-means the transmission of physical characteristics from parents to children through the genes.genetic Factor influence the height, weight, bodystructure, the colour of the eye, the texture of thehair, and even intelligence and aptitudes.Diseases and conditions such as heart disease,diabetes, obesity, etc.can also be passed through the genes, thereby affecting the growth and development.

2) Environmental Factor-The environment plays a critical role in the development of children.Some of the environmental factors influencing early childhood development involve the physical surroundings the a geographical conditions of the place the childlives in, as well his social environment and relationships with family and peers.

3)Hornmone-Hormones belong to the endocrine system. and influence the various functions of Our bodies.They are produced by different gland.Their functioning is critical for normal physical growth and the development in children. During puberty, the gonads produce sex hormones which control the develoment the growth.

Ans-3)Throughout the lifetime of the human brain undergo changes.there are 5 stages of human brain development.

1)Stage 1: 0 to 10 months-

Neurons and connections growing time.Pregnant woman should stay as stress-free as possible, take folic acid, B6 & B12, stimulate this to developing brain with sounds and sensations. Mother should avoid alcohol consumption.

2)Stage 2: birth to 6 years-

Development of voluntary movement, reasoning, perception. A sense of self is developing and life experiences shape the emotional well being.By age six, the brain is 95% its adult weight and peak of energy a consumption.

3)Stage 3: 7 to 22 years-

The neural connections or ‘grey’ matter is still pruning, wiring of brain still in progress, the fatty tissues surrounding neurons the white matter increase and assist with the speeding up electrical impulses and stabilize connections. The prefrontal cortex is the last to mature and it involves the control.

4)Stage 4: 23 to 65 years-

the brain reaches at it's peak power around age 22 and lasts for 5 more years. Afterwards, it’s a downhill pattern starts.Best approach is to stay mentally active, learn new things, stay physically active and eat a very healthy diet. Avoid toxins, cigarettes, alcohol.

5)Stage 5 older than 65 years-Brain cells are lost of the critical areas such as the hippocampus responsible for processing memories.these why learn new skills are difficult.Avoid stress or incorporate stress reducing meditation and exercises.in this stage low level of dopamine leads to various neurogenerative disorders.

Ans-4)Pleiotropic Gene are the genes which shows the genetic effect of a single gene on multiple phenotypic traits.

Pleiotropic gene are provided the information about the valuable genes and the information regarding to the evolution.action canbe the limit the rate of multivariate evolution when natural selection, sexual selection or artificial selection.Some gene evolution is harmful to an organism.