Power Point 1(mcn)

GROWTH AND DEVELOPMENT Prof. Angelica Cruz Hernande, RN

GROWTH AND DEVELOPMENT  Course Description

The course encompasses growth and development from fertilization to senescence with emphasis on various developmental tasks in every lifespan cycle

GROWTH AND DEVELOPMENT  General Objectives

At the end of the course, the students are expected to have a clear understanding pf the significance of developmental tasks in every part of the lifespan cycle.

GROWTH AND DEVELOPMENT  Specific Objectives Students are expected to: 1. List down the different theories of various G&D theorists: Sigmund Freud, Erick Erickson, Harry Stack Sullivan 2. Enumerate the importance of the “life span cycle” : from fertilization ( birth, childhood, adolescence, adulthood, elderly) to end of life. 3. Have an understanding of the effects of the environment to G&D

GROWTH AND DEVELOPMENT Evaluation Prelim Examination 20% Midterm Examination 20% Final Examination 30% Quizzes 10% Reports 10% Attitude/Attendance 100%

10%

GROWTH AND DEVELOPMENT Definition:

GROWTH AND DEVELOPMENT Stages of Fetal Growth  The Zygote  The Embryonic Stage  The Fetal Stage

The Zygote  Sperm penetrates an ovum -> zygote  Fertilization : Fallopian Tube (FT)  Sex cells are haploid : 23 chromosomes each

-> diploid cell containing 46 chromosomes  Contains genetic information : DNA Genotype Phenotype – physical characteristics  Continuously divides as it travels the FT

A SINGLE SPERM ENETRATES AN OVA

The Zygote : Pre-implantation Embryo  Cell division continues -> Blastocyst  Blastocyst :

reaches the Uterus on day 5 endometrial implantation occurs approximately between days 6-10 composed of 2 cell layers inner cell layer -> fetus an amniotic fluid outer cell layer -> trophoblast and placenta

The Embryonic Stage  Lasts from 2 weeks to 2 months  Embryo is approximately 1 – 1.5 inches long  Period of massive cell differentiation and synthesis  Initially, cell doubles in 24 hrs  Three cell layers form

Ectoderm : Mesoderm : Endoderm :

outer layer – CNS, hair, skin middle layer – muscles, organs, bones, excretory system inner layer – glands, endothelial portion of the GIT, RT, excretory sys

The HUMAN EMBRYO AT 31 DAYS

EMBRYONIC and FETAL DEVELOPMENT  Fetal stage :

12 weeks – 38 and up to 42 weeks Up to Month 1 ++  Heart beats  Neural tube (-> brain and spinal cord) forms  6 weeks : RBC begin to form  Arm and leg buds appear

Up to Month 1 ++  Brain develops into 5 areas  Some cranial nerves become visible  Eyes and ear structures begin to form  Formation of tissue that develops into

the vertebra and some other bones  Heart beats regularly  Movement of rudimentary blood through main vessels

The EMBRYO AT 5 – 6 WEEKS

Up to Month 2 ++  7 wks : 1st ultrasound

   

to confirm pregnancy to exclude molar or ectopic pregnancies to confirm cardiac pulsations to measure crown to rump length for dating Fetus’ hand quite big; upper limb resemble paddles Heart begins to separate into 4 chambers Blood is circulating throughout the body Intestines form within the umbilical cord, later migrates to abdominal cavity

Up to Month 2 ++  Footplates appear with the beginning of toe         

rays External ears now present Fetus is 10 – 13 mm long : cherry size Cells that will become testes or ovaries arrive but there is no obvious gender Muscle contractions begin Early movement not yet perceptible Eyelids more developed External features of ear take their final form Facial features continue to develop Intestines rotate

The Fetus at 2 Months ++ The fetus at 8 weeks

Up to Months 3 and 4 ++ 12 – 16 weeks ++  Fetus

length : 60 – 65mm ; 2 – 2.5 inches weight : 14 gms  Able to swallow and absorb discharge fluids  Hands complete  Fingernails growing  Tooth buds appear  Face with distinct human appearance  Amniotic sac contains 50cm3 : 1.5 oz  Placenta produces progesterone

The FETUS AT ABOUT 4 MONTHS

Up to Month 3 ++ 12 weeks ++  Eyelids close; will not reopen until the 28th wk  Face is well formed  Limbs long and thin genitalsappear and are

well differentiated  RBCs produced in the liver  Head makes up almost half of fetus; size  Can make a fist  Tooth buds appear for teeth

Up to Month 4 ++ 16 weeks ++  Fetal length 12cm crown to rump  Fetal weight 3 oz  Fetal head held high  Limb movements in coordinated manner  Eyes are closer together; face forward;  Start to blink  Tiny toenails form  Ultrasound : sucking reflex; thumb sucks  Gender now recognizable  CNS GIT complete

The FETUS AT ABOUT 16 WEEKS

Up to Month 4 ++ 12 Weeks ++  Fingers toes well defined  Eyelids close; will not reopen till 28 weeks  Face well formed  Limbs long & thin  Genitals well differentiated  RBC produced in liver  Head makes up nearly half of fetal size  Makes fist w/ fingers  Tooth buds appear  At 4 months organ formation almost complete

Up to Month 4 ++ 12 Weeks ++  Early Ultrasound:

gestational sac seen at 4.5 weeks 5.5 weeks fetus can be observed and measured confirms site of pregnancy  Color flow mapping clearly depicts blood f in fetal blood vessels in a real time scan flow direction determined by different colors  Color doppler Indispensable in the diagnosis of congenital heart abnormalities

Additionals for Months 3 - 4  Peripheral reflexes  Placenta fully formed  Fetal movement  Eyes, ears, nose, mouth approach typical

appearance  Nerve myelinization commences; (complete at 1 year)  Fetal length : 6 – 7 inches C to R  Fetal weight : 5 oz

Up to Month 5 ++  Fetus ingests and absorbs large quantities of amniotic         

fluid Kidneys excrete urine Sleeps/wakes at regular intervals Eyelids still fused Lanugo hair covers entire body Eyebrows and lashes appear Fetus more active w/ increased muscle development Mother can feel fetus move Fetal hearbeat audible by stethoscope Vernix caseosa protect fetus’ skin

Up to Month 5 ++  Female :

ovaries contain 6M eggs uterus now well formed  Fetal length : 8-12 inches C to R  Fetal weight : .5 to 1lb

ULTRASOUND at 20 WEEKS

Up to Month 6 ++  Fetus viable’ can survive NICU  Has fingerprints/footprints  REM has begun  Eyebrows, eyelashes well formed  All eye parts developed  Has hand and startle reflex  Air sacs in lungs  Fetal length  Fetal weight

: 21 cm C to R : 1lb 6 oz

A FETUS AT 24 WEEKS

Up to Month 7 ++  Sucks thumb  Responds to light and sound  Eyelids formerly shut begin to open along with new set      

of eyelashes Fetus appears a lot like how it’ll look at birth Skin wrinkled due to amniotic fluid immersion Rapid brain development Nervous system developed enough to control some body functions Respiratory system developed as to allow gas exchange Weight gain : .5 to 1 oz/day

Fetus 26 – 28 weeks

Up to Month 8 ++  Growth continues  Store nutrients  Head movement : side to side  Rapid increase in body fat  Rhythmic breathing movement;  Lungs not fully mature  Bones fully developed but soft and pliable  Body starts to store iron, calcium and phosphorus  Fetal length  Fetal weight

: 38cm C to R : 3lbs 12 oz

Fetus at 32 weeks

Up to Month 9 ++  Lungs developed  Feels pain and hunger  Lanugo begins to disappear  Body fat increases  Fingernails reach the fingertips  Fetal length  Fetal weight

: : gains .5lb/week

At 36 weeks