Human Growth and Development - Section 1, Lesson 2,3,4

When is an APGAR test done after birth?

1 to 5 minutes

what is assessed during APGAR testing

Activity (Muscle tone, assessed by touching baby’s palm), Pulse (heart rate), Grimace (response to stimulus, such as by stroking foot), Appearance (Baby’s color), and Respiration. score of 0 to 2 is given for each

what APGAR score is cause for concern?

less than 5

postpartum maternal concerns: what are the baby blues

feelings of sadness in mother beginning 3-5 days post birth, disappearing withing 10 days post birth. not the same as PPD

postpartum maternal concerns: what is post-partum depression

depression with feelings of hopelessness, issues sleeping, and issues bonding with the baby. Changing hormones thought to be cause.

postpartum maternal concerns: what are risk factors for PPD?

<age 20, family history of depression, substance use, and stress.

postpartum maternal concerns: can post-partum mood disorders (ie, depression and mania) occur without psychotic features?

yes

postpartum maternal concerns: what is associated with post-partum psychosis?

hallucinations and delusions (such as those that the infant is possessed or the infant should be killed)

postpartum maternal concerns: how common is post-partum psychotic features?

occur in 1 in 500 to 1000 births, more common in women with previous post-partum mood disorders.

postpartum maternal concerns: What is post-partum anxiety?

empathy and anxiety heightened to toxic levels (brain areas related to both affected by rise of oxytocin “bonding chemical”), to the point of intrusive thoughts of baby being harmed and heightened alertness.

overall physical growth of baby: what is the average weight and length of a baby?

7.5 lbs, 20”

Overall physical growth of baby: what percentage of bodyweight do babies typically lose?

5%, due to waste elimination and adjusting to feedings. More concerning for smaller infant. Temporary and followed by rapid growth

Overall physical growth of baby: by when does a baby’s weight double, triple, or quadruple?

4 months, 1 year, 2 years

Overall physical growth of baby: what is the approximate length of a 1 year old and 2 year old?

29.5, 34.4

Overall physical growth of baby: what percent of the body does the baby’s head take up at different stages?

50% in utero, 25% at birth, 20% by age 25

Motor development of baby: how does motor development occur?

from reflexive actions (like sucking and rooting) to more advanced motor function

Motor development of baby: what paths does development occur?

cephalocaudal (head to tail) and proximodistal (midline outward)

Motor development of baby: what are examples of the paths of development?

baby lifting head, sitting with assistance (then unassisted), crawling, pulling up, cruising (walking while holding onto something).

Motor development of baby: what does it mean for there to be milestones based on age?

there is an average age for each milestone (ie, babies on average can hold up head at 6 weeks, 90% of babies achieve this between 3weeks and 4 months.

Motor development of baby: how old are babies when they can sit alone, on average?

7 months (most babies acheive between 5 and 9 months of age)

Motor development of baby: regarding developmental milestones, what is of concern?

several delays that require being addressed by pediatrician

Motor Skills of baby: what does this refer to?

ability to move the body and manipulate objects

Motor Skills of baby: what do fine motor skills refer to?

focus on muscles in fingers, toes, and eyes and enabling coordination of small actions (grasping toy, writing with a pencil, using spoon).

Motor Skills of baby: can newborns grab voluntarily?

no, but they can wave arms towards objects of interest

Motor Skills of baby: when can a baby purposefully reach for an object with both arms then a few weeks later, one arm?

at about 4 months of age. Palmar grasp (fingers and palm involved, no thumb involvement)

Motor Skills of baby: when can a baby use their forefingers and thumbs in their grasp, greatly enhancing grasping ability?

at about 9 months of age. baby can also reach for moving objects

Motor Skills of baby: what are gross motor skills?

skills that focus on large muscle groups that control the heads, torso, arms, and legs. Include balancing, running, jumping. ALSO include bring chin to chest when lying down, moving chest up, and rocking back and forth. Also includes exploring object with feet

Sensory capacities of baby: why is vision one of the most poorly developed sense at birth?

because of how dark the womb is. Time after birth is needed to build neural pathways between brain and eyes. The part of the eye that makes up the central part of the retina and allows people to see sharp detail is not fully developed at birth and doesnt reach adult levels of development until 15 months

Sensory capacities of baby: how far away from the babies face can it see?

8-10 inches

Sensory capacities of baby: what is the vision of an 8 week old?

20/300

Sensory capacities of baby: what is the vision of a 3 month old?

20/200 (baby can see top letter E on vision chart)

Sensory capacities of baby: what are possible visual limitations up to 45 months?

cones in eye not fully grown

Sensory capacities of baby: can babies see color

young infants can perceive color if they are very pure forms of basic colors (Ie, bright red or green as opposed to pastels)

Sensory capacities of baby: what type of stimuli do infants prefer to orient towards?

face-like. They also prefer upright and non-scrambled faces. Can easily distinguish mother’s face from other’s faces.

Sensory capacities of baby: what do one-month-olds focus on when looking at a face vs 2 month olds?

outer edges of face. 2 month olds focus more on the eyes.

Sensory capacities of baby: what age shows difficulty disengaging from visual stimulus and sometimes fixating for several minutes?

1 month olds. eyemovements during tracking are jerky, and lag (improve at 2 months) until about 3-4 months of age.

Sensory capacities of baby: What visual field do newborns orient towards?

side of the head rather than either side of the nose

Sensory capacities of baby: When is binocular vision evident by?

3 months, continues developing through six months

Sensory capacities of baby: An infants sense of hearing is very keen. When is it evidenced by?

month 7 of pregnancy. Newborns also prefer their mother’s voices to other females and also register specific information in utero from the mother or father

Sensory capacities of baby: by what age can babies distinguish between familiar and unfamiliar sounds?

as early as one monthj after birth

Sensory capacities of baby: how soon can babies develop a preference for smell?

as soon as 6 days. Example is preference to turn towards mothers breast as opposed to other women

Sensory capacities of baby: infants are said to view the world in an intermodal way. what does this mean?

Through stimulation of more than one sense. ex: when sucking on a pacifier with a specific texture, they prefer looking at an image of the same texture.

At what age can infants match lip movements with speech correspondance

4 months

What is habituation testing?

tests measuring decreased response to stimulus after repeated presentations

What is the first breast milk produced after birth?

Colostrum, also called liquid gold. It is rich in nutrients and antibodies. Changes and becomes thinner 3rd to 5th day after birth

What are benefits of breast feeding?

Children who are breastfed have lower rates of childhood leukemia, asthma, obesity, type I or II DM, and SIDS

how long does the USDSSH recommend only breastfeeding and breastfeeding?

until six months of age, until 1-2 years of age

How can breastfeeding benefit the mother?

Breastfeeding stimulates contractions in the uterus to help it regain it’s normal size. Women who breastfeed are more likely to space their pregnancies farther apart. Breastfeeding lowers risk of ovarian cancer, DM II, and RA.

What percentage of mother’s breastfeed their babies at some point?

83.2%, but most who breastfeed stop at 6-8 weeks (usually to return to work).

Does breastfeeding benefit maternal-infant bonding more than bottle feeding?

no, studies indicate both are the same.

When should solids be introduced?

When the infant is ready (lifts head on own without wobbling, sits up on it’s own, shows interest in foods others eat, is hungry after breastfeeding, able to move food from front to back of mouth, able to decline food)

When can breastmilk typically be supplemented with more solid food?

4-6 months old. finger foods, peeled fruit, etc can be introduced at 10-12 months.

How should new foods be introduced to the baby?

one at a time, for a few days at a time to allow for adjustment and assess for allergy.

What foods should be avoided due to choking hazard or other issues for babies?

sticky (ie, peanut butter or taffy), large chunks (ie, cheese and meat), or firm and round (ie, grapes or tomatoes). Honey and and corn syrup also to be avoided, due to botulism spores that can cause death to those below 12 months.

what is an issue babies in developing countries or war torn countries face?

two types of malnutrition. Infantile marasmus (starvation due to lack of calories and protein) and kwashiorkar (“disease of displaced child”, often occurring after another child starts breastfeeding instead. child loses appetite and abdomen swells as body breaks down vital organs for protein).

While rates of wasting have been dropping worldwide, how many children under age 5 are suffering worldwide from wasting and severe wasting? (according to UNICEF and WHO)

50 million, 16 million.

What are the consequences of wasting?

dependent on how early treatment is sought.

What can wasting lead to?

cognitive issues, behavioral issues, and poor attention

What is the basic building block of a nature perspective?

gene

What is a gene?

basic physical unit of inheritance passed from parent to offspring,

What do genes control?

control the manufacture of proteins in the body, which is responsible for influencing the structure and function of cells.

Where is a gene located?

on chromosomes

What is a chromosome?

structure found in the nucleus of a cell that is made up of proteins and DNA organised into genes. Each cell normally contains 23 pairs.

How are most cells in the body made after conception?

mitosis

The cells used in sexual reproduction (gametes. ova and sperm) use meiosis. How does this work?

gamete’s chromosomes duplicate then divide twice, resulting in 4 cells containing only half of the genetic material of the original gamete. Thus, the ova and sperm only have 23 individual CHROMOSOMES each.

what is the likelihood of having offspring that are genetically identical (and NOT twins)?

one in trillions

Of 23 pairs of chromosomes, how many are similar in length?

22 pairs. remaining pair (sex chromosomes. typically xx or xy, if individual not intersex) may differ.

what does genotype refer to?

the sum total of all genes a person inherits.

what does phenotype refer to?

features that are actually expressed

What does homozygous refer to?

receiving the same version of a gene from a parent

What does heterozygous refer to?

refers to receiving a different version of a gene from each parent.

What happens in a homozygous situation?

a physical characteristic is displayed as a result of a person receiving the same version of a gene from each parent

What does it mean when a gene is dominant?

genes express themselves in a phenotype, even when paired with a different version of the gene. Silent partner is the recessive

When do recessive genes express themselves?

only when paired with a similar version of the gene

Most characteristics are not the result of a single gene and are, instead, polygenic. what does this mean?

They are the result of several genes

What is it called when a dominant gene does not completely suppress a recessive gene?

incomplete dominance

What is an example of incomplete dominance?

sickle cell disease. The gene producing the healthy, round cell is dominant. The recessive gene leads to a sickle shape of the cells, which can clog veins and deprive vital organs of oxygen and increase risk of stroke

What happens with carriers of sickle cell disease when they are typically unaffected by it, but are then in situations of oxygen deprivation (ie, physical exertion or high altitudes)?

they may experience some symptoms of sickle cell disease

when do monozygotic (identical) twins occur?

a fertilized egg splits into 2 within 2 weeks of development and the resulting offspring are genetically identical.

How many twins are monozygotic?

about 1/3rd

what happens when 2 eggs are separately fertilized?

dizygotic

who are more likely to have dizygotic twins?

older mothers and couples who use fertility drugs

most known genetic disorders are dominant-gene linked, but the majority are not debilitating. What are examples?

tourettes and huntington’s* (*fatal and affects nervous system, but typically doesn’t make appearance until midlofe)

Recessive-gene disorders are less common, but may be more life threatening. what are examples?

cystic fibrosis and sickle cell, due to less likely to be detected

What is a sex linked disorder?

defective gene on X chromosome. Men are at greater risk due to having only one X. examples include hemophilia, color-blindness, and baldness. Women need defective gene on both chromosomes, but if defective gene is dominant, equally at risk.

what are homozygous recessive disorders?

Individual inherits gene change from both parents. Individual is simply a carrrier if they inherit a gene from one parent.

homozygous recessive disorders: What are stats for sickle cell disease?

disease where red blood cells are sickle-shaped, which interferes with ability to transport oxygen to various parts of the body. Affects 1 in 500 births to black parents and 1 in 36000 births to Latino parents.

homozygous recessive disorders: What are stats for cystic fibrosis?

condition that affects breathing and digestion due to thick mucus build up, due to thicker mucus. Affects 1 in 3500 births

homozygous recessive disorders: What are stats for phenylketonuria?

metabolic disorder where individuals cannot metabolize phenylalanine (amino acid). Intellectual deficits occur if left untreated. easily detected and treated with special diet. affects 1 in 10,000 births

homozygous recessive disorders: What are stats for Tay-Sachs disease?

caused by enzyme deficiency resulting in accumulation of lipids in nerve cells of brain. Results in progressive damage of cells and decrease in cognitive and physical development. Causes death typically by age 5. 1 in 4000 births. 1 in 30 Jewish Americans are a carrier, 1 in 20 French Canadians are a carrier.

homozygous recessive disorders: What are stats for albinism?

Individual lacks melanin and possesses little to no pigment in skin, hair, or eyes. Vision problems can occur. fewer than 20,000 cases in US per year

What is an autosomal-dominant disorder?

individual only needs to inherit one gene change from a parent.

autosomal-dominant disorder: What are stats for huntingtons disease?

disease that affects individuals nervous system. Nerve cells become damaged, causing different cells of brain to deteriorate. Disease affects behavior, movement, and cognition. Fatal, occurring at midlife. 1 in 10,000 births

autosomal-dominant disorder: what are stats for tourette syndrome?

disorder that results in uncontrollable motor and vocal tics as well as body jerking. 1 in 250 births

autosomal-dominant disorder: what are stats for Achondroplasia?

most common form of disproportionate short stature, individual has abnormal bone growth, disproportionally short limbs, short fingers, a large head, and specific facial features. 1 in 15000-40000 births

Sex-linked disorders: what is it?

when X chromosome carries the faulty gene (referred to as X-linked disorder). Men more commonly affected because they only carry one X and no other X to counter the X with the faulty gene.

Sex-linked disorders (X-linked): What are stats for fragile X syndrome?

body cannot make enough protein for the brain to grow. Behavioral and learning difficulties can occur. 1 in 4000 males, 1 in 8000 females.

Sex-linked disorders (X-linked): what are stats for hemophilia

problems with blood clotting. leads to internal and external bleeding. 1 in 10000 males.

Sex-linked disorders (X-linked): what are stats for duchene muscular dystrophy?

weakening of muscles resulting in inability to move, wasting away, possible death. 1 in 500 males

What is a chromosomal abnormality?

Too many or tew few chromosomes present. Most common cause is mother’s age, due to older ovum being more prone to suffering abnormalities due to environmental factors. Consequently, some gametes do not divide evenly during formation and some cells have more than 46 chromosomes.