Moduel 3.2

Question 1

Do you know what is meant by these principles of growth differentiation?

Answer 1

EXPAND
Simple to complex

Homogeneous to heterogeneous

General to specific

Question 2

3 Growth Directions:

Answer 2

Cephalocaudal: Growth occurs from “head to tail”: the upper end of an organism develops faster and before the lower portion (maturation from head to hands and feet)

Proximodistal: Growth occurs from the middle (central axis) to extremities (near to far)

Bilateral: Growth occurs on both sides at the same time: growth is symmetrical

Question 3

Define:
Karyotype
gestation
conceptus

Answer 3

Karyotype: a visual depiction of chromosome number and shape

Gestation: The prenatal period is that period of development from conception (fertilization] until birth

Conceptus: The product of fertilization is termed a zygote

Question 4

The Placenta

Answer 4

• Placenta is disk-shaped and about 9 inches long, weighing about 1 lb.
• It usually delivers about ½ hour following birth (this represents the final stage of delivery).
• It enables passage of substances without directly exposing fetus to maternal blood.
• While also serving as a filter or protective barrier against some infective agents, the placenta is permeable to others, including alcohol.

Question 5

Gestational period

Answer 5

40 weeks (280 days) (38 - 42 weeks is full term baby)

2 ways of describing prenatal developmental sequence

• by dividing gestational period into 3 equal trimesters
• by physiological stages (germinal, embryonic, fetal)

Question 6

Developmental Sequence P

Answer 6

Gestational Period:
FIRST TRIMESTER
most basic body structures formed
SECOND TRIMESTER
growth and refinement
THIRD TRIMESTER
weight increases by about 6 lbs & length by about 8 inches

Physiological Stages:
GERMINAL
zygote implants, rapid cell division occurs
EMBRYONIC
90% of 4500 body organs & structures
FETAL
growth in size & weight
refinement of tissues & organs

Question 7

What Starts Labour

Answer 7

The exact trigger of labour is not completely known, but a prominent view is that oxytocin receptor sites increase in smooth muscle of uterus throughout pregnancy, and at a critical point where growth and pressure is sufficient enough, oxytocin (hormone) is released by the hypothalamus and the sensitized uterus begins to contract.
The amniotic sac (bag of waters) may burst just before or during labour or during birth.

Question 8

3 stages of labour

Answer 8

1. Early Labour & Active Labour (Active Labour occurs at 4 cm dilation of cervix)
2. Baby is Born (usually within 2 hours following 10 cm dilation)
3. Delivery of Placenta (about ½ hour after birth of baby)

Question 9

Braxton-Hicks

Answer 9

= False Labour. Tends to occur in the weeks before due date (most often during first pregnancy). May function to thin and soften the cervix (more pliable for dilation and delivery).

Question 10

What happens during actual labour

Answer 10

the cervix begins to dilate and the mucus plug is lost. At 4 cm. mother is said to be in “active labour” (there are 3 stages of labour and delivery).

At 10 cm. most babies deliver within 2 hours [as short as 20 mins. and as long as a few hours] (average labour & delivery period for 1st time mothers is 12 hours). “Crowning” is when the head of the baby shows.

An Episiotomy may be needed to ease delivery (small cut to enlarge vaginal opening to assist birth: not used as much over recent decades).

Question 11

Epidural Anesthesia

Answer 11

may be requested to help mother deal with pain and discomfort of labour & delivery. Other forms of anesthesia also exist.

Anesthesia given in the epidural space of lower back (above dura mater [outermost layer of 3 layers of meninges or membranes that cover spinal column]).

Helpful in easing pain and discomfort of childbirth. It can slow down the process a bit (contractions are typically not felt as strongly, and the urge to push is not as prominent.

Question 12

Folic acid

Answer 12

If contemplating pregnancy, 0.4 mg (400 mcg) of folic acid per day is recommended:

Folic acid (folate) is a B-Complex vitamin found in leafy green vegetables, liver, eggs, orange juice, peanuts, beans, broccoli, asparagus, peas, lentils, enriched grain products, fortified breakfast cereals, and most multivitamins.

Folic acid is taken prior to getting pregnant in order to maximize effectiveness.

Among other things, folic acid is required for healthy neurological development of the fetus. Adequate folic acid intake is associated with reduced incidence of spina bifida.

Question 13

Spina bifida types

Answer 13

Spina bifida occulta
Bony abnormality seen by x-ray Relatively common (5-10% of general population)

Open spina bifida
Or “spina bifida manifesta”
The diagnosis of open spina bifida is usually made at birth or during prenatal ultrasound screening.

Question 14

Teratogens

Answer 14

a substance that interferes with normal growth and development and causes malformations

The effect of a teratogenic agent depends on:

• The strength of the teratogen
• The timing of the teratogen (While strength and duration are important considerations, as a general rule, exposure during the first trimester has the potential to be more traumatic than exposure during other trimesters. This is because it’s during the first trimester that most structures and organs are developing).
• The duration of exposure to the teratogen

Question 15

Smoking & Pregnancy

Answer 15

When a mother smokes during pregnancy, the baby is more likely to be born pre-term and at a low birth weight

Low birth weight is correlated with several long-term health issues
For example, inhibited growth throughout life, and susceptibility to chronic diseases later in life

Question 16

Alcohol & Pregnancy

Answer 16

-Alcohol passes through placental barrier & is not well broken down (metabolized) by immature infant
-The blood alcohol content of the fetus is therefore greater than that in the mother
-Similar to other teratogens, prenatal effects of exposure to alcohol depend on:
>Timing (which trimester[s]): though morphological effects generally occur in the first trimester, because the brain continues to develop and is sensitive throughout the pregnancy, neurological/developmental/cognitive effects can result during all trimesters.
>Amount consumed (and how often [duration])
>Genetic makeup of fetus
>Mother’s ability to metabolize (breakdown & excrete) alcohol

The most severe type of Fetal Alcohol Spectrum Disorder is Fetal Alcohol Syndrome [FAS].

• facial characteristics
• growth retardation
• neuro-developmental challenges
• maternal alcohol use

Question 17

3 specific ways teratogens can impact fetus

Answer 17

mutagenetic (effect DNA composition, effects growth and development) 
environmental teratogens (how cells act or react or how they multiply)
epimutagenetic teratogens  (effect the epigenome, the molecular expression of DNA without changing the DNA itself)

Question 18

Toxoplasmosis

Answer 18

A fetus may contract toxoplasmosis through the placental connection with its infected mother
The mother may be infected by: improper handling of cat litter, handling or ingesting contaminated meat

Question 19

Rh Incompatibility

Answer 19

Occurs when Rh- mother carries and Rh+ fetus. If mixing of blood occurs, mother’s immune system becomes sensitized and develops antibodies against fetus’s Rh factor. If not detected, this can have serious consequences for fetus.

In most cases, the first child is not at risk. Mothers are usually not sufficiently sensitized until after the birth of their first baby. When this occurs, subsequent fetuses are placed at risk.

In most cases, Rh- mothers are identified, and if carrying an Rh+ fetus (determined through amniocentesis or umbilical cord blood sample), precautions are taken.

Throughout the pregnancy, the mother’s blood is monitored for the prevalence of antibodies (through the “Coombs Test”). If antibodies reach a threshold amount, then the fetus will likely receive a blood transfusion of Rh- blood. The transfusion occurs through the cord.

Question 20

APGAR Test

Answer 20

-First assesment done on infant
A = appearance
P = pulse
G = grimace
A = activity
R = respirations

A score is given for each sign at one minute and five minutes after the birth. If there are problems with the baby an additional score is given at 10 minutes. A score of 7-10 is considered normal, while 4-7 might require some resuscitative measures, and a baby with an APGAR score of 3 and below requires immediate resuscitation.

Newborns with a score of 3 or less are 3 X as likely to have neurological problems.

The results of assessments like the Apgar simply gather data. If the assessment reveals something concerning, the individual is usually sent for more advanced diagnostic testing.

Question 21

metabolic disorders

Answer 21

metabolic disorders are passed along by recessive means and are the result of genetic mutations that cause the DNA code to be disrupted (missing base element), resulting in a missing enzyme and failure to metabolize certain substances.

Many of these disorders can be treated with dietary modifications.

Tandem Mass Spectrometry is used to assess for as many as 30 disorders with one drop of blood from the heel prick.

Involved in bodys ability to break down substances or create one the body needs
Important to test newborns because If body can’t break down the substances they can build up and become toxic. If the body cant create substances, it can have a toxic effect on the body which is cumalitive where the longer it goes the worst the effects can be.

Question 22

What is a screening test?

Answer 22

Screening tests are laboratory tests that help to identify people with increased risk for a condition or disease before they have symptoms or even realize they may be at risk so that preventive measures can be taken. They are an important part of preventive health care.

Screening tests help detect disease in its earliest and most treatable stages. Therefore, they are most valuable when they are used to screen for diseases that are both serious and treatable, so that there is a benefit to detecting the disease before symptoms begin.

Question 23

What are the characteristics of good screening instruments?

Answer 23

• Can be administered in short time
• Don’t require highly specialized and extensive training to administer
• Have clear Pass/Fail criteria
• High sensitivity and specificity
• Do what they’re supposed to do [are valid]

A good screening instrument must have sensitivity, which is the ability to correctly determine who does have the condition

A good screening tests must also have specificity, the ability to correctly determine who does not have the condition

Question 24

Lanugo

Answer 24

A soft, downy covering of hair, mostly on shoulders, the back of extremities, the forehead and temples

Question 25

Vernix Caseosa

Answer 25

Composed of sebum (the oil of the skin) and cells that have sloughed off the fetus’ skin.

Vernix is theorized to serve several purposes, including moisturizing the infant’s skin, and facilitating passage through the birth canal. (Without vernix, and living in a watery environment for 9 mos. the baby would likely be born wrinkly.)

Question 26

Commonly, neonatal jaundice occurs for two reasons

Answer 26

Commonly, neonatal jaundice occurs for two reasons:
Infants have too many red blood cells. It is a natural process for the baby’s body to break down these excess red blood cells, forming a large amount of bilirubin. It is this bilirubin that causes the skin to take on a yellowish color.

A newborn’s liver is immature and cannot process bilirubin as quickly as he will be able to when he gets older. This slow processing of bilirubin has nothing to do with liver disease. It merely means that the baby’s liver is not as fully developed as it will be, and thus, there is some delay in eliminating the bilirubin.

Question 27

Fontanels

Answer 27

Babies are born with anterior, posterior, sphenoidal and mastoid fontanels

Fontanels: soft spots [tough membrane] permitting passage through birth canal and brain growth. Posterior closes after about 2-3 months, with anterior closing between 8 and 18 months

Question 28

Define:
Milia
Mottling
Mongolian spots

Answer 28

Milia: tiny white bumps or yellow spots across the tip of the nose or chin, caused by skin gland secretion. They appear raised but are nearly flat and smooth to the touch. They disappear in the first two to three weeks of life.

Mottling: splotchy; uneven discolouration of skin

Mongolian spots: are very common in any part of the body of dark-skinned babies. They are flat, gray-blue in color (almost looking like a bruise), and can be small or large. They are caused by some pigment that didn’t make it to the top layer when baby’s skin was being formed.

Question 29

2 Kinds of Birthmarks

Answer 29

Vascular birthmarks are caused by blood vessels that have accumulated below the surface of the skin. They range in color from pink to red to bluish, depending on the depth of the blood vessels.

Pigmented birthmarks – usually brown, gray, bluish, or black – result from an abnormal development of pigment cells.

Question 30

Hemangioma

Answer 30

May be present at birth, or appear in the first months of life
Are usually pale, pink, flat patches with normal skin texture found on the forehead, eyelids, nose, upper lip, or nape of neck
Turn pale with pressure
May become lighter or darker with changes in room temperature
Fade by 18 months (except those on nape of neck)

Question 31

Babinksi reflex

Answer 31

Occurs when the great toe flexes toward the top of the foot and the other toes fan out after the sole of the foot has been firmly stroked. This is normal in younger children, but abnormal after the age of 2.

In children over the age of 2 and adults, the opposite reflex normally occurs (the toes curl inward) – this is called the plantar response.

Disappears at about 9-10 or 12 months. Persistence past that age may indicate a neurological disorder.

This reflex is replaced by the plantar reflex in adults.

Question 32

Rooting Reflex

Answer 32

Turns in direction of stroke on cheek. Disappears at 3-4 months, but may persist during sleep to 9-12 months

Question 33

Startle or Moro Reflex

Answer 33

Occurs with sudden change of position or loud noise. Both arms extended outward with fingers spread, then brings together in a grasping, quivering embrace.

Question 34

Stepping Reflex

Answer 34

Holding baby upright with feet touching a flat surface causes legs to prance up and down as if baby were walking or dancing. Disappears at about 2-4 months.

Question 35

Pre-Speech Pattern

Answer 35

–>Differentiated cry at about 2-3 months
–>Cooing and babbling at about 2-3 months
–>Lalling - consistsoftheinterspersingofbabblingwithpauses,inflections,andintonationsfromwhattheinfanthears.
–>Holophrase development
Word or word fragment that stands for a whole thought. For example “Da?” = “Where is daddy?”
–>On average vocabulary consists of about 6 words at the end of infancy [1st word usually btwn 10-14 months]
–>Between 9 – 12 months, an infant typically recognizes own name & names of familiar objects and people; responds to “no” & echoes & imitates sounds
–>By about 18 months; by the end of infancy, the child may possess a vocabulary of about 50 words.

Question 36

Prolactin

Answer 36

• Increased serum concentrations of the hormone prolactin during pregnancy cause enlargement of the mammary glands and increases the production of milk.
• However, the high levels of progesterone during pregnancy act directly on the breasts to stop ejection of milk.
• It is only when the levels of this hormone fall after childbirth (after delivery of placenta) that milk ejection is possible.

Question 37

Oxytocin

Answer 37

Oxcytocin functions to promote contractions during child birth, but also causes squeezing around milk sacs (alveoli) when the baby is sucking.

Question 38

Formula feeding:

Answer 38

• Mothers who are undergoing chemotherapy for cancer and moms who are infected with HIV should not breast feed.
• Mothers with hepatitis should check with their doctors.
• Women who have had breast surgery may have difficulty breast feeding.
• Some women may have inverted nipples that make breast feeding difficult.
• Women who have survived trauma or abuse may have difficulty breastfeeding.

Question 39

Harlow’s Rhesus Monkey Experiments

Answer 39

He took infant monkeys away from their real mothers, giving them instead two artificial mothers, one model made of wire and the other made of cloth. The wire model was outfitted with a bottle to feed the baby monkey. But the babies rarely stayed with the wire model longer than it took to get the necessary food. They clearly preferred cuddling with the softer cloth model, especially if they were scared. (When the cloth model had the bottle, they didn’t go to the wire model at all.)”

“In another study, Harlow found that young monkeys reared with live mothers and young peers easily learned to play and socialize with other young monkeys. Those with cloth mothers were slower, but seemed to catch up socially by about a year. Babies raised with real mothers but no playmates were often fearful or inappropriately aggressive. Baby monkeys without playmates or real mothers became socially incompetent, and when older, were often unsuccessful at mating. Those unsocial females that did have babies were neglectful of them. From his studies, Harlow concluded that sex alone did not drive societies, nor did mother love enable individual social relations. Rather, normal sexual and parental behavior depended on a wide array of affectional ties with peers and family early in life.”

Question 40

Postpartum Depression

Answer 40

As many as ½ of women experience some depression following birth, with about 20% experiencing serious depression.

Feeling restless or irritable.
Feeling sad, depressed or crying a lot.
Having no energy.
Having headaches, chest pains, heart palpitations, numbness, or hyperventilation.

Question 41

Postpartum Psychosis

Answer 41

In about 1 in 1000 births, a woman may experience postpartum psychosis, with rapid mood changes, deep depression and hallucinations.

(There is some evidence for there being an inherited risk for postpartum psychosis, with chromosome 16 implicated.)