Physical development across our lifespan

Part 1- Physical development during prenatal development

During the germinal stage, the zygote is several cells that become a blastocyst. A blastocyst looks like a ball with several little balls squished inside of it. The blastocyst breaks down into different structures. These structures will become the umbilical cord, amniotic sac, the lining of the placenta, and the embryo. Once implantation has taken place, around 2 to 8 weeks, the brain, spine, eyes, nose, mouth form and the embryo's heart begins to beat. The head is large during this stage while the arms and legs are just little buds. During the fetus stage, which takes place at the start of the third month through the birth of the baby, the fetuses organs begin to function and its genitals begin to form. At this point, the babies skin is still see through but will begin to thicken soon. About half way through the mothers pregnancy, around 20 weeks, the fetuses ears, nose and lips are becoming recognizable. The fetuses little buds now look like arms and legs and it can move stretch, kick and even suck it's thumb and the head is also more proportionate to the body. Around the 7th month, the fetus has fattened up, the bones have hardened and its fingernails have grown. The fetus now looks like a baby.

Part 2- Physical Development During Infancy

The sequence of physical development starts from cephalocaudal to proximodistal. Infants gain control of their trunks and shoulders before their extremities and fingers. The same goes for the lower half. They control their hips and upper legs prior to having control of their lower legs, feet, and toes. In the first 5 months of life, the infant will double their weight, and triple it by their first birthday. The infants height will increase by 50% by it's first birthday. About 90% of the time, the infants are not growing. They have little growth spurts where a lot happens in a little amount of time. Research has shown that the child will not grow for the first 63 days and then grow one-fifth of an inch in less than 24 hours. In the child's second year, they will grow an additional 4 - 6 inches and gain another 4 -7 pounds. Growth rates of taller children tend to slow while shorter children will speed up. Neonates extremities tend to be the same length. By the first birthday, the arms and legs have grown. Arm will grow quicker than the legs. Children who suffer from FTT have impaired growth. If a child is able to get help, they can go through what is called canalization. With proper nutrients, the child can "catch-up".

For the first year of a child's life, this child experiences so many different experiences from not being able to hold itself up to walking. Motor development in an infant develops from cephalocaudal to proximodistal, like physical development, and very quickly. As early as 1 month old, an infant can hold it's head up, then follows by lifting it's chest up while lying on it's stomach. An infant experiences motor skills rapidly within the first year of life. At 3 months of age an infant can start to reach for things unsuccessfully, but within a month or two can now grasp the item. An infants grasp around ages four to 6 months is strong and may not let go of the object unless distracted. Infants start holding things by using the ulnar grasp around 4 to 6 months old and then by 9 to 12 months will begin to use it's pincer grasp. Another quick development is around 6 months of age when a child begins to become mobile. The infant can roll around on the floor and get to more places. Within a months time, this child that has been rolling all over the place can now sit up. Within the next few months the child will go from sitting, to crawling, then walking.

Part 3- Physical development in early childhood-

In early childhood a child can gain 6 pounds a year and grow 2 - 3 inches per year. At age 2 the brain is 75% of it's adult weight and by 5 years old, the brain is now at 90% of it's adult weight. The most important thing to take place in the brain is the reticular formation and growth of the hippocampus. RF regulates attention and concentration while the hippocampus is responsible for memories. Handedness begins around 4 months of age. The child will start to use one hand over the other at this stage.

Gross motor skills begin around 18 -24 months where the child runs awkwardly. 2 - 3 yrs old a child now runs easily. At 3 - 4 yrs old a child can now walk up the stairs, 4 -5 yr old's can go up and down the stairs and at 5 - 6 yrs old children can now walk in straight lines, and skip.

Fine motor skills develop slower than gross motor skills. They slowly begin to gain control of their wrists and hands. An 18-24 month old and turn a page in a book, a 2 - 3 year old can throw a ball while standing, 3 - 4 year old can catch a ball, 4 -5 year old can hold a pencil correctly, and 5 and 6 year old's can thread needles.

Physical development in middle childhood-

Middle childhood development takes place around ages 6 - 12 yrs. Every year a child will grow "about 2", unless they are like my youngest son and grow 4" a year. Growth spurts for males and females are not equal. Boys tend to be bigger than girls are around 9 - 10 years old until the girl catches up and surpasses the boys around 10 yrs old. Girls will continue to grow until ages 13 - 14 where boys will then begin to catch up. Around ages 11 boys will begin to gain muscle whereas girls will gain fat. At age 12, boys will have reached 84% of their adult height and girls will be at 94% of their adult height.

Part 4- Physical Development in Adolescence-

Physical changes begin to take place around age 11, sometimes sooner or later, and ends around age 19. There are 2 different types of sex characteristics, primary and secondary.

Primary= ovaries, vagina, uterus and fallopian tubes in girls. Penis, testes, prostate, and seminal vesicles in boys

Secondary= breast development and body hair in girls. Body and facial hair, and deepening voice in boys

Adolescences will grow on average 3"-6" at this stage of development.
Girls hips tend to broaden, whereas boys shoulders will broaden
Females will experience menarche and boys will have spermarche around the age of 13, some even earlier
Breasts start to grow on females around 8 or 9 years old
Males testes will start to enlarge at age 11.5. The penis will have a growth spurt about a year later with pubic hair to follow
Females will start to have pubic hair and underarm hair around age 11

In the early stages, adolescences are self-conscious of their bodies and the physical changes they are experiencing, but by the age of 18, they will become more satisfied with their bodies.

Part 4 - Physical Development in Early Adulthood-

In early adulthood, there are two types of aging:

-Primary Aging: physical signs like gray hair and wrinkles

-Secondary Aging: aging due to environmental factors like daily exposure to polluted air, smoking, alcohol use, poverty

At this stage in your life, between your 20's and 30's, you have reached your peak. Men and women will start to have a decline in fertility, women more than men.
The brain begins to stabilize
A trend in obesity and living in stressful situations
It is more common in 15 - 24 yr old's to have STD's due to their risky behavior

Part 5- Physical development during Middle adulthood

As we age, we continue to see gradual changes in our bodies. Our hair starts graying, wrinkles appear, and we even begin losing our hair. Our health starts to decline, more rapidly than those exercise and eat healthy.

Vision declines in our 40's, making it difficult to read small print, and then by age 60 some will have a condition called presbyopia. This is a condition where the eye lens loses it capacity to adjust to objects at varying distances.
Hearing begins to decline around age 50. Men's hearing tends to decline more rapidly than women's.
Skin becomes less firm and begins to thin. Wrinkles appear on our foreheads, around our eyes and mouths.
Sexuality changes occur in our reproductive systems. Women experience menopause diminishing their fertility capabilities and cessation of a women's menses. Male's sperm motility decreases and fertility diminishes.
Diseases and other health related problems are more prominent as we age. Cancer and CVD are the leading causes of death in middle age. Men are more vulnerable than women to health problems because they engage in more risky behavior and they are more apt to not see their doctors when needed and don't get yearly physicals.

Part 5- Physical development during Late Adulthood

Life expectancy is the number of years that a person can expect to live. Women tend to live about 5 years longer than men. The reason for this is men are involved in more risky behavior, don't have yearly physicals, or see their doctors when needed.
Physical declines become more apparent in late adulthood, as organs and systems of the body are affected. But, with exercise and healthy eating you can extend your life.
Central nervous system begins to decline. Brain weight declines and we being to lose gray matter.
Sensory changes become increasingly noticeable. We begin to lose our hearing and eyesight, and our taste, smell, and touch sensitivity decline. Cataracts become an increasing problem from middle to late adulthood. Hearing loss is due to excess ear wax, calcified bones, and degeneration in the nerve pathway.
Osteoporosis is common at this stage in life. Moreso in women than men due to menopause and the declining levels of estrogen.
Sleep disorders are more prominent at this stage in life due to the changes in brain structures controlling sleep. Older adults require less sleep, usually around 4 - 7 hours depending on your age.
Dementia and Alzheimer's disease are health problems we face in late adulthood. Dementia can be caused by depression, CVD, drug intoxication, Parkinson's, etc. Alzheimer's is the 5t leading cause of death in older Americans. This is a very severe form of dementia. The actual diagnosis of Alzheimer's cannot be diagnosed accurately until after death. The progression of Alzheimer's starts with memory difficulties, and repetitive conversations then progress into forgetting names of common objects and performing common activities.

References

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https://sites.google.com/site/developmentalpsy2014/home/physical-development

[Child putting shapes into container]. (n.d.). parenting.firstcry.com

https://parenting.firstcry.com/articles/physical-development-in-early-childhood/?ref=interlink

[Children riding a bike and scooter]. (n.d.). mytext.cnm.edu

https://mytext.cnm.edu/lesson/chapter-7-middle-and-late-childhood/

[Elderly hand and infant foot]. (n.d.). Miro.

https://miro.medium.com/max/1100/1*WfUrE25Vx7yP5yM2N_GWDQ.jpeg

[Infant to walking toddler]. (n.d.). Study.com.

https://study.com/cimages/videopreview/defining_the_principles_of_growth_121019.jpg

[Middle ages woman looking in mirror]. (n.d.). huffpost.com