Prenatal Development

Question 1

Meiosis

Answer 1

Process where cells containing 23 pairs of chromosomes divide into daughter cells containing one half of each chromosome pair

Question 2

Mitosis

Answer 2

Process where cells create an exact copy of themselves including all 23 pairs of chromosomes

Question 3

What is a teratogen?

Answer 3

Potentially harmful environmental agents are called teratogens that can cause long lasting effects on subsequent development.

Drugs, disease, foods and other environmental influences on the mother can alter prenatal development

Question 4

Medical model of care

Answer 4

Model of maternity care guided by the belief that pregnancy and birth are potentially dangerous life processes that must be medically managed.

Question 5

Midwifery model of care

Answer 5

Views pregnancy and birth as normal, inherently healthy life processes.
Woman-centered model
Associated with a decrease in epidurals, episiotomies, and caesarean surgeries.

Question 6

Critical period

Answer 6

A finite window of opportunity for a given feature of development to emerge. If that feature does not develop normally during its critical period it will never have a second chance no matter how strong the environmental influences.

Question 7

Sensitive period

Answer 7

Interval of heightened plasticity (high potential to change)when environmental influences are most efficient at affecting an organism’s development.
Example: first 2 years babies appear to have sensitive periods in all of their sensory systems.
Prenatally, sensitive periods are when the brain and organs are most sensitive to teratogens.

Question 8

The prenatal development stages are:

Answer 8

●GERMINAL STAGE- 0-2 weeks post-conception
zygote becomes a multicellular organism called a blastocyst through the process of mitosis. It travels down the fallopian tube. Germinal stage ends when the blastocyst implants in the thick nutrient-heavy lining of the uterus, called the endometrium.

● EMBRYONIC STAGE- 2- 8 weeks post-conception
Organs as well as the support system for the developing organism begin to develop. This is a critical time in prenatal development because organ formation can be very highly vulnerable to outside influences. By end of embryonic stage the embryo has features that resemble arms, legs, hands and fingers along with differentiated facial features, including eyelids.

●FETAL STAGE - 8 weeks post-conception to birth (approx 38 weeks post-conception)
Fetal stage is a time of rapid growth and increasing functionality. The fetus also becomes increasingly active, with mothers feeling first fetal movements, called quickening, around the four month mark.

Question 9

Genotype is

Answer 9

An individual’s collections of genes.

Made up from one set of chromosomes from our mother and one set from our father.

Question 10

Phenotype

Answer 10

The observable characteristics of an individual.

A multitude of phenotypes can result from the same genotype.

Question 11

Stages of labour

Answer 11

●Dilation
Period of labour when cervix is opening, also known as the 1st stage of labour.

●Descent and birth-
Once cervix is fully effaced (thinned)and dilated to approx 10cm the SECOND stage or pushing stage of labour begins, ending with the birth of the baby.

●Delivery of the placenta-
Third stage of labour - begins with babys body fully emerged and ends with expulsion of the placenta. Immediately after baby is born, placing the baby skin to skin to the mothers chest helps to regulate the baby’s body temp and facilitate early bonding and breastfeeding.

●Postpartum period-
Fourth stage of labour - lasting approx 6 weeks after childbirth. In this time, the women’s body adjusts to motherhood and resumes a non pregnant state.

Question 12

Caesarean surgery

Answer 12

The mothers abdomen is cut and the fetus removed.

Question 13

Apgar scale

Answer 13

Scoring system that assesses the health of newborns based on 5 areas:
-Activity and muscle tone (limp, some movement, actively moving)
-Heart rate (absent, slow, rapid)
-Reflexes (no response, grimace, cry)
-Skin colour (blue or pale membranes, pink body, blue legs/arms, pink all over (fingernails, membranes)
-Respiration (absent, irregular breathing, strong cry)
Done at 1 and 5 minutes after the baby is born. Newborns who score 3 or under need immediate medical attention.

Question 14

Verly low birth weight

Answer 14

Birth weight of less than 1, 500 g (3.3 lbs)

Question 15

Normal birth-weight

Answer 15

Birth weight of 2.5 to 4.5 kg (5.5 to 9.92 lbs)

Question 16

Placenta

Answer 16

A short-lived multifunctional organ (forms along the uterine wall) that passes nutrients from the mother’s blood into the embryo.

Question 17

Amniotic sac

Answer 17

Takes shape around the embryo to protect the developing organism from shocks and abrupt temperature changes.

Question 18

Zygote

Answer 18

A fertilized ovum in which the male and female gametes have united in one cell

Question 19

Gamete

Answer 19

A Male or female cell that contains 23 chromosomes in their singular form

Question 20

Ovulation

Answer 20

Process (typically happens monthly) that causes an ovum to ripen and be expelled by the ovaries

Question 21

Dominant gene

Answer 21

The quality of an allele that influences the expression of a trait.

Question 22

Recessive gene

Answer 22

An allele that can only influence the expression of a trait in the absence of a dominant allele.

Question 23

Alleles

Answer 23

T

Question 24

Autosomes

Answer 24

The first 22 pairs of chromosomes are called autosomes.

Question 25

Infant mortality rate

Answer 25

The number of infant deaths occurring in the first year of life per 1,000 live births.

IMR steadily decreased between 1990 and 2015 with an average reduction of 2.1 (per 1,000 live births) each decade. 7 deaths per 1000 live births in 1990 and 5 deaths per 1000 in 2000. It remained there until 2015 where it fell to 4 deaths per 1000 live births.
However Canada was unable to meet the 2015 millennium developmental goal of 3 deaths per 1000 live births.

Question 26

Cephalocaudal pattern

Answer 26

A pattern of physical growth that proceeds from the head down through the long axis of the body. (Base of the spine)
Happens in embryonic stage

Question 27

Proximodistal pattern

Answer 27

Embryo differentiates from the spine through the limbs. (Center of body through the appendages)
Happens in the embryonic stage

Question 28

Nucleus

Answer 28

Center of each cell is the nucleus . Inside the nucleus of every cell except for the sperm and ova is 46 chromosomes, arranged in 23 pairs.

Question 29

Sex chromosomes

Answer 29

The 23rd pair of chromosomes which contain the Gene’s that determine biological sex characteristics (xx for female) and by for Male.

Question 30

DNA

Answer 30

Made up of 4 chemicals

• adenine (A)
• guanine (G)
• thymine (T)
• cytosine (C)

Key quality: A always pairs with T a d G always pairs with C.

Question 31

Genes

Answer 31

Most basic units of heredity.
A microscopic structure made of thousands of links of chemical particles that combine to create and build all the parts of a living being.

Question 32

Locus

Answer 32

Gene’s on each chromosome are arranged in a particular sequence.
The specific place of a gene on a chromosome is called a locus.

Question 33

Organogenesis

Answer 33

Early development and differentiation of the internal organs such as the lungs, heart, and gastrointestinal systems.

Question 34

Birth doula

Answer 34

A specially trained north companion who provides physical, emotional and informational support during labour, birth and the immediate postpartum.

Question 35

Maternal mortality rate

Answer 35

The number of maternal deaths per 100,000 live births.

Question 36

Low birth weight

Answer 36

Birth weight of Less than 2,500 g (5.5 lbs)

Question 37

Preterm

Answer 37

Baby born earlier than full gestational period, usually less than 37 weeks.

Question 38

Small for gestational age

Answer 38

Birth weight of less than 2.5 kg for an infant with a gestational age that is normal (37 + weeks)

Question 39

Postpartum doula

Answer 39

Specially trained advisor and helper who provides physical, emotional and informational support to women and their families during the postpartum period.

Reduces likelihood of postpartum depression

Question 40

Lying-in period

Answer 40

A circumscribed period of time for postpartum women and their babies to rest and recover from birth.