human growth
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Human Growth. & Development. List a developmental milestone in human growth & development. What is the relevance?. Medical professionals need to understand stages of growth of development. Growth ~ refers to the measurable physical changes that occur throughout a person’s life. - PowerPoint PPT PresentationTRANSCRIPT
Human Growth
& Development
List a developmental
milestone in human growth &
development
What is the relevance?
• Medical professionals need to understand stages of growth of development.Growth ~ refers to the measurable physical
changes that occur throughout a person’s life.Development ~ refers to the changes in
intellectual, mental emotional, social and functional skills that occur over time
What is the relevance?
• Different periods of life present unique challenges, changes, and problems.
• How one handles those challenges influences their health and the next stage in their lives.
Growth and Development
• Each phase of growth and development contains four major parameters– Physical development– Intellectual-cognitive development– Psycho-emotional development– Social development
Physical Development
• Bodily changes• Often times measurable–Height / weight–Muscle development–Changes in body organs
Intellectual-Cognitive Development
• Thinking skills– Learning how to solve problems– Make judgments– Deal with situations
Psycho-Emotional Development
• Changes in feelings– Love– Hate– Joy– Fear– Excitement
Social Development
• Interactions and relationships with other people– Family– Friends– Business associates
Growth and Development
Each of these parameters contain numerous developmental milestones.
Developmental Milestones ~ significant points in the growth process
Developmental Milestones
• Progress from the simple to the more complex– Person learns to sit, then crawl, then stand , then
walk, and then run– Children learn “gross” motor skills such as walking
first then learn “fine” motor skills such as using a crayon
Principles of Growth and Development
• Each stage establishes the foundation for the next stage.
• Stages proceed in an orderly pattern• ****However, the rate of progress varies
among individuals.*****• Health care providers must understand that
each life stage creates certain needs in individuals.
Principles of Growth & Development
- Development is influenced by genetics- Genes ~ units of hereditary material contained in
human cells- Each person’s set of genes is unique
- Environment also influences an individual- Do you believe we are more a product of our
environment, our heredity, or both? Why? - Discuss your stance with your neighbor
Miracle of life Part 1
At what point do you believe that a fertilized egg becomes a “person”?
Conception through Teenage Years• Pregnancy lasts 10 lunar months (40 weeks/ 9
calendar months/ 266-280 days)– Consists of 3 trimesters of 3 months each(1st, 2nd, 3rd)
(Below: Fetus at 16 weeks)
(Conception)
Growth and Development During Each Trimester
Trimester Length of Time Growth and Development
First Trimester Conception through third month
Development of major organ systems
Second Trimester Fourth through sixth month
Refinement of organ systems
Third Trimester Seventh through ninth month
Weight gain and maturation
First TrimesterThe First Trimester
Key Terms (First Trimester)
• Ovum ~ human egg of the female– About the size of a pencil dot on paper
• Sperm ~ male reproductive cell – Too small to see with the human eye
• Conception = Fertilization– Union of the nuclei of the egg and the sperm
• Fallopian tube ~ tube that extends from the uterus to the ovary
Ovary, Fallopian Tube, Uterus
What Happens the First Trimester?
• Conception occurs when one sperm, traveling with millions of other sperm, penetrates the ovum.
• Conception occurs in the first third of the fallopian tube
Timing is Everything
• In the female ovulation occurs at midcycle , around day 14.
• The egg lives for about 24 hours after ovulation.
• Sperm usually live between 12 and 48 hours.– (some survive up to 72 hours)– Female sperm live longer*
Timing is Everything
• For fertilization to occur, sexual intercourse must take place around the time of ovulation, generally no earlier than 72 hours before ovulation and no later than 24 hours after ovulation.
• Reflex ovulators ~ women who ovulate in response to having intercourse– Rabbits are reflex ovulators
How Fertilization Occurs
• During intercourse, about 200-600 million sperm are released.
• Only about 100,000 survive the acidic environment of the vagina.
• Sperm swim through the uterus and into the fallopian tube towards the egg.
• Within 1-2 hours they are gathered around the egg.
How Fertilization Occurs
• One (and only one) sperm penetrates the egg and unites with the nuclei of the egg.
• Zygote ~ fertilized egg*
How Fertilization Occurs• The single-cell zygote has 46 chromosomes,
23 from the egg and 23 from the sperm.• The zygote begins to divide, forming
clusters of cells that slowly makes its way through the fallopian tube toward the uterus. (3-5 days)
• The cells (morula) look like a cluster of grapes with a root like structure on the back which will become the placenta.
How Fertilization Occurs
• When this cluster of cells reaches the uterus, it implants itself into the plush lining, where it grows and develops into a human being with billions of cells.
• Implantation ~ embryo adheres to uterus lining.• Implantation occurs when the cluster attaches
itself into the upper rear wall of the uterus
How Fertilization OccursAmniotic sac develops over this group of cells– A membrane that surrounds the fetus– The outer group of cells starts to develop into a
shape that is the head and a tail• Embryo ~ human being growing in the uterus
from the time of conception to about the eighth week.
How Fertilization Occurs
http://www.webmd.com/baby/slideshow-conception
• the great sperm race
Pro life or Pro Choice? Why???
****JUST AS YOU HAVE YOUR OWN OPINION, SO DO OTHERS!
RESPECT THEIRS AS WELL!!****
The First Trimester• 21-25 days, a heart begins to beat
and nervous system starts to develop!
• 4 weeks: embryo is ¼“ long– Arm buds bulge– Consists of head, body, and tail– Eyes and ears can be detected
• 5 weeks: a nose is visible• 6 weeks: almost ½”, floating in
amniotic sac– Leg buds appear
• 7 weeks: ¾” and can move hands– Fingers are defined, organs are visible,
skull bones are growing.
Embryo at 3 wks
Embryo at 7 wks
The End of the 1st Trimester• 8 weeks: almost 1”, liver is
large, bones are forming, testes and ovaries are distinguishable– At 8 weeks, developing
infant is called a fetus• 10 weeks: 1 ½”– 2”,
kidneys produce urine, lower trunk muscles develop– About to end the 1st
trimester– baby peeing in womb
Fetus at 10 weeks
The 2nd Trimester• 12 weeks: begins the 2nd
trimester; head is 1/3 of the entire length, ribs can be seen, hair begins to grow
• 16 weeks: 4 ½” long, weighs 3-4 oz; human looking face, testicles of males position for descent. (can tell sex of fetus)– Mother feels fetal movements,
known as “quickening”– Fetus blinks and begins sucking– Heartbeat can be heard with
fetal instruments (fetal doppler)– Hearing fetus heartbeat
Fetus at 14 weeks
Fetal doppler
2nd Trimester (cont.)
• 20-24 weeks: 12” long, major systems continue to develop, bones continue to form. – Fetus may suck its
thumb– Eyes remain sealed
closed– Survival at this point
of pregnancy is unlikely
• Fetus ~ end of 8th week till birth
3rd Trimester• 28 Weeks: 14” and 2.5 lbs– Viable with an
increased threat from infection & immaturity
• Major developments in 3rd tri: weight gain, growth in length, & maturation of organs
• Although viable, best place for growth & development is the uterus!
• 38-40 weeks = FULL TERM• Fetal influences: whatever the
mother consumes (alcohol, drugs, and tobacco can harm infant even in small amounts)
• fetus growth
The Placenta• Disc shaped structure about 7” in diameter
and 1” thick.• Highly vascular• Site where nutrients and waste are exchanged
between mother and baby.• Oxygen, food and other nutrients diffuse from
the mother’s blood to the embryo’s• Carbon dioxide and other waste diffuse from
the embryo’s blood into the mother’s blood to be excreted.
• placenta images