Transcript Class #2

Human
Growth
and
Development
Day #2
June 15, 2012
Fort Omaha 8 a.m. – 4:55 p.m.
Agenda for Class #2
• Roll Call Game
• Variables Activity
• Brief review of Genetics and Human
Development
• Review of Prenatal development notes
• Questions and Complete test answer sheet
• Film: In the Land of Giants
• Notes on infancy and early childhood
development
Correlation
• Correlation – a relationship in which two or more
variables change together
– Positive correlation – both variables change in the
same direction
• The more you study, the higher your grades
will be.
– Negative correlation – one variable increases as
the other decreases
• The more checks you write, the lower your bank
balance will be.
Sample Hypothesis
• Liver cell transplantation will reduce the need
for dietary management for patients with
phenylketonuria (PKU).
• IV =
• DV =
Sample Hypothesis
• Liver cell transplantation will reduce the need
for dietary management for patients with
phenylketonuria (PKU).
• IV = Liver cell transplantation
• DV = need for dietary management
Opening Day Survey
• Hypothesis: Men and women will differ in their
preference for comfort/snack foods.
• Men are more likely to prefer salty or savory
snacks whereas women are more likely to prefer
sweet foods.
• IV = sex of the individual (variables are never the
people; the variable is some characteristic of the
person)
• DV = snack/comfort food preference; salty or
sweet foods
Survey Results
(combined classes to allow for larger sample)
Sex
Sweet
Salty/Savory
Not scored
Male
7
7
1
Female
16
20
1
Total (N=52)
23
27
2
Can I support my hypotheses?
If I were on a committee working with the
bookstore and food service/
vending for the College,
how might I use these results?
On your notecard, write your name,
6/15/12 and identify the variables.
• Hypothesis 1
– Men are more likely to have more than $20 cash in
their wallets than women.
– IV =
– DV =
• Hypothesis 2
– Open-mindedness and critical thinking skills improve
with the more years of education one has completed.
– IV =
– DV =
• Hypothesis 3
Babies who are born to older fathers are likely to
live longer lives than babies who are born to
younger men.
– IV
– DV
• Hypothesis 4
Strokes are more likely to occur for people who
sleep less than 5 hours per night than for people
who sleep more than 5 hours per night.
– IV
– DV
Genetics and
Genetics and
Human
Development
Human Genetics
• Each of us began life as a single cell
weighing about one twenty-millionth of
an ounce
• This cell contained our entire genetic
code
Chromosomes
• Nucleus of each human cell contains
chromosomes
• thread-like structures made up of
deoxyribonucleic acid, or DNA.
• DNA is a complex molecule that has a
double helix shape, like a spiral staircase,
and contains genetic information
DNA Molecule
For more detail: http://www.youtube.com/watch?v=CkcFqif7H5k&feature=related
Genes
• Genes - units of hereditary information
– short segments of DNA
• Genes direct cells to reproduce
themselves and to assemble proteins
• Proteins
– the building blocks of cells
– the regulators that direct the body’s
processes
(Mader, 2008)
Enduring Nature of Genes
• Three processes by which cells split
and are formed
–Mitosis
–Meiosis
–Fertilization.
Mitosis
• All body cells, except the sperm and egg, have
46 chromosomes arranged in 23 pairs
• These cells reproduce by a process called
mitosis
• During mitosis, the cell’s nucleus—including
the chromosomes—duplicates itself and the
cell divides
• Two new cells are formed, each containing the
same DNA as the original cell.
http://www.youtube.com/watch?v=rgLJrvoX_qo&feature=related
Meiosis
• Sex cell division is different type of cell
division
• Eggs and sperm (or gametes) are formed in
meiosis
• A cell of the testes (in men) or ovaries (in
women) duplicates its chromosomes but then
divides twice, thus forming four cells
• Each of these has only half of the genetic
material of the parent cell.
• By the end of meiosis, each egg or sperm has
23 unpaired chromosomes.
http://www.youtube.com/watch?v=kVMb4Js99tA&feature=related
Fertilization
• During fertilization, an egg and a sperm
fuse to create a single cell, called a zygote
• In the zygote, the 23 unpaired
chromosomes from the egg and sperm
combine to form one set of 23 paired
chromosomes
• One chromosome of each pair is from the
mother’s egg and the other from the
father’s sperm.
• Each parent contributes half of the
offspring’s genetic material.
•
http://www.youtube.com/watch?v=vXNaTRs83hE&NR=1
The 23rd Pair of Chromosomes
• Ordinarily, in females the 23rd pair
consists of two chromosomes called X
chromosomes
• In males the 23rd pair consists of an X
and a Y chromosome
• The presence of a Y chromosome is what
makes an individual male
So, is this the karotype of a girl or a boy?
Genotype and Phenotype
• Genotype -- all of a person’s genetic
material
• Phenotype -- observable characteristics
• Phenotypes include
– physical characteristics (such as height,
weight, and hair color)
– psychological characteristics (such as
personality and intelligence)
Genetic Principles
• Dominant-recessive genes
• Sex-linked genes
• Polygenically determined characteristics
Dominant-Recessive Genes Principle
• Dominant -- one gene of a pair always
exerts its effects
• Recessive gene – exerts its influence only
if the two genes of a pair are both
recessive
– may be overridden by a dominant gene
– May be carried from generation to
generation but not expressed in phenotype
Sex-Linked Genes
• X-linked inheritance -- mutated gene is carried
on the X chromosome
– very different implications for males than females
(Turner, 2006)
– males have no “backup” copy to counter the
harmful gene
– females have a second X chromosome, which is
likely to be unchanged
• Females who have one changed copy of the X gene are
known as “carriers”
Polygenic Inheritance
• Genetic transmission is usually quite
complex
– Few characteristics reflect the influence of
only a single gene or pair of genes
• polygenically determined characteristics - determined by the interaction of many
different genes
Chromosome Abnormalities
• Down syndrome -- caused by the
presence of an extra copy of
chromosome 21
– once in every 700 live births
– Women aged 16 - 34 are less likely to give
birth to a child with Down syndrome
• Sex-Linked Chromosome Abnormalities
Sex-Linked Chromosome
Abnormalities
• Klinefelter syndrome – extra X
chromosome
• Fragile X syndrome -- results from an
abnormality in the X chromosome
– X chromosome becomes constricted and
often breaks
• Turner syndrome -- females have either
an X chromosome missing or part of one
X chromosome is deleted
• XYY syndrome – male has extra Y
Gene-Linked Abnormalities
• Phenylketonuria (PKU) – individual
cannot properly metabolize
phenylalanine, an amino acid
– once in every 10,000 to 20,000 live births
– left untreated, phenylalanine builds up in
the child, producing mental retardation and
hyperactivity
• Sickle-cell anemia -- genetic disorder that
impairs the body’s red blood cells
– most often in African Americans
– red blood cell becomes a hook-shaped
“sickle” that cannot carry oxygen properly
– 1 in 400 African American babies is affected
• 1 in 10 African Americans is a carrier
• 1 in 20 Latin Americans is a carrier
• Other diseases that result from genetic
abnormalities
– cystic fibrosis
– diabetes
– hemophilia
– Huntington disease
– spina bifida
– Tay-Sachs disease
PRENATAL DEVELOPMENT AND
BIRTH
Three Trimesters
• The germinal and embryonic periods occur in
the first trimester
• The fetal period begins toward the end of the
first trimester and continues through the
second and third trimesters
• Viability (the chances of surviving outside the
womb) occurs at the beginning of the third
trimester.
• Age of viability – about 23-24 weeks on
average
The Fetal Period
• Fetal period begins two months after
conception and lasts for seven months
• Three months after conception-- fetus is about
3 inches long; weighs about 3 ounces
• At birth, the average American baby weighs 7
½ pounds and is about 20 inches long
http://www.cerebralpalsyinfo.com/CP1.jpg
Multiple Births
• Monozygotic - identical
– One ovum and one sperm
– Splits early in the process of dividing
– Must be the same sex
• Dizygotic – fraternal
– Several ova each fertilized
– No more alike than other siblings
– May be boys, girls or one (some ) of each
• Increased incidence with fertility technology
Dionne Quintuplets
• http://www.youtube.com/watch?v=KNleSaDse24&feature=related
• http://www.youtube.com/watch?v=WCmvQ2vdMv0
Conjoined Twins
• Monozygotic twins who do not completely
separate
• Parts develop individually and other parts
develop and grow together
• Example: the Hensel twins from Minnesota
• http://www.youtube.com/watch?v=7ZUzi0Rh
BpM&NR=1&feature=endscreen
• http://www.youtube.com/watch?v=ISlXC33N2
b4
Teratogens
• Despite complexity, most babies are born
healthy
• Most hazards are avoidable
• Teratology—study of birth defects
– teratogens—broad range of substances that
can cause environmental insults that may
cause prenatal abnormalities or later
learning abilities
Timing of Exposure
• Critical period—in prenatal
development, the time when a
particular organ or other body
part is most susceptible to
teratogenic damage
-entire embryonic period is
critical
Amount of Exposure
• Dose and/or frequency
• Threshold effect—teratogen relatively
harmless until exposure reaches a
certain level
Amount of Exposure, cont.
• Interaction effect—risk of
harm increases if exposure to
teratogen occurs at the same
time as exposure to another
teratogen or risk
The Birth Process
• The Birth Process
– first stage -- contractions cause the woman’s
cervix to stretch and open
• longest of the three stages
• typically lasts 12 to 24 hours
– second stage begins when the baby’s head starts
to move through the cervix
– 45 minutes – 1 ½ hours, depending on number of
pregnancies
– third stage is afterbirth
• placenta, umbilical cord, and other membranes are
detached and expelled
• shortest of the three birth stages
Where and Who?
• Where do births take place?
– In U.S., 99% take place in hospitals
– Home births are far more common in many other
countries
• Who assists?
–
–
–
–
Obstetricians and nurses
Fathers or birth coaches
Midwives
Doula -- a caregiver who provides continuous physical,
emotional, and educational support for the mother
before, during, and after childbirth
Cesarean Delivery
• Breech position – buttocks rather than head
emerge first
– Can prevent the baby from breathing normally
• Cesarean delivery -- the baby is removed from
the mother’s uterus through an incision made
in her abdomen
– May be lifesaving but carry the risks of major
surgery
From Fetus to Newborn
• Anoxia -- fetus or newborn has an insufficient
supply of oxygen
– Cause of brain damage
• Immediately after birth, the umbilical cord is
cut and the baby is on its own
• Almost immediately after birth, a newborn is
taken to be weighed, cleaned up, and tested
Apgar Scale
• Used to assess the health of newborns at 1
and 5 minutes after birth
• A score, or reading, of 0, 1, or 2 on each of
these five health signs
– heart rate, respiratory effort, muscle tone, body
color, and reflex irritability
• identifies high-risk infants who need resuscitation.
Apgar Scoring
• Activity (muscle tone)
0 — Limp; no movement
1 — Some flexion of arms and legs
2 — Active motion
• Pulse (heart rate)
0 — No heart rate
1 — Fewer than 100 beats per minute
2 — At least 100 beats per minute
• http://www.babycenter.com/0_the-apgar-score_3074.bc
• Grimace (reflex response)
0 — No response to airways being suctioned
1 — Grimace during suctioning
2 — Grimace and pull away, cough,
or sneeze during suctioning
• Appearance (color)
0 — The baby's whole body is completely bluish-gray or pale
1 — Good color in body with bluish hands or feet
2 — Good color all over
• Respiration (breathing)
0 — Not breathing
1 — Weak cry; may sound like whimpering, slow or irregular
breathing
2 — Good, strong cry; normal rate and effort of breathing
Threats to Newborns
• Low birth weight
• LBW -- less than 5 ½ pounds at birth
• Very low birth weight - under 3 pounds
• Extremely low birth weight - under 2 pounds.
• Preterm
• born three weeks or more before the pregnancy has reached its
full term
• Small-for-date
• birth weight is below normal when the length of the
pregnancy is considered
Incidences and Causes of Low Birth
Weight
• Low birth weight and preterm births often
occur together
• Incidence of low birth weight varies
considerably from country to country
– Related to
• Poverty
• Maternal health status
• Maternal nutrition
Consequences of Low Birth Weight
• More health and developmental problems
than normal-weight infants (Moss, 2006).
• At school age, more likely to have a learning
disability, attention deficit hyperactivity
disorder, or breathing problems such as
asthma (Wocadlo & Rieger, 2006).
Bonding
• Bonding -- formation of a connection,
especially a physical bond, between parents
and the newborn in the period shortly after
birth
• Bonding is inhibited by
– Anesthesia during labor
– Hospital policies that separate mothers from
infants
The Postpartum Period
• Postpartum period -- lasts for about six weeks
after childbirth or delivery or until the
mother’s body has completed its adjustment
and has returned to a nearly prepregnant
state
• Physical and psychological adjustments
Physical Adjustments
• Fatigue can undermine the new mother’s
sense of well-being and confidence in her
ability to cope with a new baby
• Dramatic changes in hormone production
• Involution -- process by which the uterus
returns to its pre-pregnant size
Emotional and Psychological
Adjustments
• Baby blues -- two to three days after birth,
many women begin to feel depressed,
anxious, and upset
• Postpartum depression -- a major depressive
episode about four weeks after delivery
– strong feelings of sadness, anxiety, or despair that
for at least a two-week period inhibit coping with
daily tasks
The First Year of Life
http://www.quia.com/files/quia/users/jcarterfauchier/gabrielle
Sensation versus
Perception
• Receiving environmental stimuli
versus
• Giving meaning to information
received by the sensory system
Neuron
Parts of a neuron
◦ dendrite
◦ cell body
◦ axon
◦ synapse
◦ myelin
A NEURON
The Brain
• Left brain processes verbal,
numerical, textual & logical
information
• Right brain processes spatial,
colored & creative information
• Hemispheres have differing functions
but don’t work independently.
Both generally work together to perform
most tasks.
– One side may be faster.
–
Left Hemisphere Rt Hemisphere
Language
Process positive
emotions
Spatial relationships;
artistic abilities
Perception & expression
of emotion; negative
emotions
The Brain
• Right and left halves are joined
by the corpus
• House calls it the
callosum.
Brooklyn Bridge
connecting the two most
important neighborhoods
• Myelination
Myelin Sheath
– Insulation on
axon to improve speed
of transmission.
– Also insulates axon from activity of
other neurons.
• http://videos.howstuffworks.com/discovery-channel/398understanding-the-brain-development-video.htm
• http://www.5min.com/Video/The-Comprehensive-NewbornScreening-326782662
• http://www.5min.com/Video/Learn-about-Your-NewbornsReflexes-96171343
• http://www.youtube.com/watch?v=_ew93pEEdMY&feature=r
elated
• http://www.youtube.com/watch?v=_ew93pEEdMY&feature=r
elmfu
• http://www.youtube.com/watch?v=hArF94sVXV8&feature=re
lmfu
Reflexes
Survival reflexes
◦ Breathing
◦ Sucking
◦ Rooting
◦ Swallowing
Other Reflexes
•Startle or Moro
•Babinski
•Walking (stepping)
•Swimming
Motor Skills
http://www.youtube.com/watch?v=DSoi_RR3pg8&feature=related
•Gross Motor Skills
large body movements such as
running, climbing, jumping and
throwing
•Earliest and easiest
to be mastered
Fine Motor Skills
are smaller body movements such
as writing drawing, buttoning,
coloring, tying shoes, using tools,
etc..
◦ require some maturation nervous
system of to develop
◦ Self feeding may be first fine motor
skill
Types of Play*
•Sensorimotor
Play
• Parallel Play
• Rough and Tumble Play
• Play Face
• Mastery Play
• Dramatic Play
* not a complete list; categories
are not mutually exclusive