Question 1

Which of the following is true of myelination?
A) It is complete at birth.
B) Myelination of the brain's prefrontal matter is completed during neonatal development.
C) The breakdown of myelin generally occurs in the first decade of life.
D) It is part of the maturation process that leads to the abilities to crawl and walk during the first year after birth.

Accepted Answer

Myelination is a process that continues after birth and is crucial for the development of motor skills, including crawling and walking. It is not complete at birth, does not finish during neonatal development for the brain's prefrontal matter, and the breakdown of myelin typically does not occur in the first decade of life but may happen in various neurological diseases later in life.

Question 2

In the context of infant nutrition, infants _____.
A) need significantly less iron, pound for pound, than adults do
B) do not need iron content in their diet
C) need significantly more iron, pound for pound, than adults do
D) need iron depending on their gender, similar to adults

Accepted Answer

Infants require significantly more iron, pound for pound, than adults due to their rapid growth and development, which increases their need for iron to support the expansion of their blood volume and the development of their brain and muscles.

Question 3

In the context of feeding infants, infant formula is widely considered _______.
A) superior to cow's milk
B) inferior to cow's milk
C) inferior to solid foods
D) superior to breast milk

Accepted Answer

Infant formula is designed to closely mimic breast milk and is fortified with necessary nutrients, making it superior to cow's milk for infants. Cow's milk lacks the appropriate amounts of iron, vitamin C, and other nutrients that infants need, and it contains high concentrations of protein and minerals that can stress a newborn's immature kidneys and cause severe illness at times.

Question 4

The introduction of whole cow's milk to an infant_________.
A) should be delayed until the infant is nine to twelve months old.
B) should be delayed until the infant is two to three years old.
C) is recommended from the time of birth of the infant.
D) is recommended by about four to six months of age.

Accepted Answer

Whole cow's milk should be introduced to an infant when they are around nine to twelve months old. Introducing cow's milk earlier can lead to iron deficiency and potential allergies, while the infant's digestive system is not yet ready to process the high concentrations of protein and minerals in cow's milk.

Question 5

Which of the following is true of neurons?
A) A neonate has lesser neurons than an adult.
B) A neonate's spinal cord contains more neurons than the brain.
C) As a child matures, axons in neurons shorten.
D) Infants are born with about 100 billion neurons, most of which are in the brain.

Accepted Answer

Infants are indeed born with approximately 100 billion neurons, the majority of which are located in the brain. This high number of neurons at birth is crucial for the rapid development and learning that occurs in infancy and early childhood.

Question 6

Alzheimer's disease is associated with which factor in concerning neuronal functioning?
A) A shortening of axons
B) A breakdown of myelin
C) A lengthening of axons
D) A reduction in the number of dendrites

Accepted Answer

The answer of Alzheimer's disease is associated with which factor...

Question 7

According to the American Academy of Pediatrics, infants should be fed breast milk _________.
A) only for the first two weeks.
B) only for the first six months.
C) for at least four years.
D) for at least one year.

Accepted Answer

The American Academy of Pediatrics recommends that infants be exclusively breastfed for about the first six months, with continued breastfeeding alongside the introduction of appropriate complementary foods for at least one year.

Question 8

The basic units of the nervous system are cells called _____.
A) ova
B) neurons
C) lymphocytes
D) neutrophils

Accepted Answer

Neurons are the basic units of the nervous system, responsible for transmitting signals throughout the body.

Question 9

Which of the following foods should not be given to infants until at least the latter part of the first year?
A) Infant formula
B) Finger foods
C) Breast milk
D) Solid foods

Accepted Answer

The answer of Which of the following foods should not...

Question 10

Which of the following statements is true of dendrites?
A) They extend trunk-like from the cell body in a neuron.
B) They are short fibers that constitute neurons.
C) They account for much of the difference in length in neurons.
D) They become shorter as a child develops.

Accepted Answer

Dendrites are short, branched extensions of the neuron that help to increase the surface area for receiving signals from other neurons.

Question 11

Messages are released from axon terminals in the form of chemicals called _____.
A) enzymes
B) neurotransmitters
C) amines
D) hormones

Accepted Answer

Neurotransmitters are the chemicals released from axon terminals to transmit signals across synapses to other neurons, muscle cells, or glands.

Question 12

The high fat content of a myelin sheath insulates a neuron from which components of the fluids that encase the nervous system?
A) Electrically charged atoms
B) Dangerous free radicals
C) Toxic cellular wastes
D) Excessive salt molecules

Accepted Answer

The high fat content of a myelin sheath primarily provides electrical insulation for neurons, which helps prevent the electrical charges carried by ions (electrically charged atoms) from dissipating across the neuron's membrane. This insulation is crucial for the efficient transmission of nerve impulses.

Question 13

Billy is a four-year-old boy. He has trouble walking and running like other children his age, and he sleeps through most of the day. He is diagnosed with multiple sclerosis. Billy's condition is the result of _____.
A) the abnormal lengths of the axons
B) a disruption in his myelin sheaths
C) the presence of an extra copy of chromosome 21
D) a disruption in his rapid eye movement sleep

Accepted Answer

Multiple sclerosis is characterized by damage to the myelin sheaths, which are protective coverings around nerve fibers in the brain and spinal cord. This damage disrupts the normal flow of electrical impulses along the nerves, leading to the symptoms observed in Billy.

Question 14

Breastfeeding is considered impractical for many women in the United States because of _______.
A) the demands of their jobs
B) the pain caused by an infant's suckling
C) inconsistencies in the amount of breastmilk produced
D) the widespread availability of superior alternatives to breastmilk

Accepted Answer

The demands of their jobs often make it difficult for many women in the United States to maintain a consistent breastfeeding schedule, leading to the perception that breastfeeding is impractical.

Question 15

In the context of neurons, which of the following is a function of the myelin sheath?
A) It facilitates the entry of electrically charged atoms in the fluids that encase the nervous system into the neurons.
B) It prevents electrical messages from traveling down an axon.
C) It facilitates the creation of neurotransmitters.
D) It minimizes leakage of the electric current being carried along an axon.

Accepted Answer

The myelin sheath acts as an insulating layer around the axon of a neuron, which helps to prevent the leakage of electrical current as it travels along the axon. This insulation increases the speed of signal transmission.

Question 16

An individual develops intellectual disability because of a disorder called phenylketonuria. Which of the following occurrences is a cause of the intellectual disability in the individual?
A) The replacement of myelin by hard, fibrous tissue in the individual's neurons
B) The inhibition of normal myelin development in the individual's brain
C) Insulation of the neurons by myelin
D) Myelination of the prefrontal matter of the individual's brain

Accepted Answer

Phenylketonuria (PKU) is a metabolic disorder caused by a deficiency of the enzyme phenylalanine hydroxylase, leading to an accumulation of phenylalanine in the body. High levels of phenylalanine can inhibit normal myelin development in the brain, which is essential for proper nerve function. This disruption in myelination is a key factor in the intellectual disability associated with PKU.

Question 17

In the context of introducing solid foods to an infant, which of the following is recommended?
A) Solid foods should not be introduced until about 12 to 15 months of age.
B) Solid foods should be introduced only when an infant is two to three years of age.
C) Solid foods should be given to an infant from birth.
D) Solid foods should not be introduced until about four to six months of age.

Accepted Answer

Solid foods are recommended to be introduced to an infant's diet around four to six months of age, as this is when they typically start to need additional nutrients and are developmentally ready to begin eating solid foods.

Question 18

Which of the following is a downside to breastfeeding?
A) An increased risk of early breast cancer and ovarian cancer in mothers
B) An increased risk of transmission of HIV to infants by infected mothers
C) An increased risk of childhood lymphoma in infants
D) The likelihood of infants developing serious cases of diarrhea

Accepted Answer

Breastfeeding can transmit HIV from an infected mother to her infant, which is a recognized downside in cases where the mother is HIV positive. The other options listed are not accurate downsides of breastfeeding; in fact, breastfeeding has been shown to reduce the risk of breast and ovarian cancer in mothers, does not increase the risk of childhood lymphoma, and helps protect infants against serious cases of diarrhea.

Question 19

Which of the following food types should infants be allowed to eat plenty of?
A) High-sugar foods.
B) High-fiber foods.
C) High-iron foods.
D) Fat and cholesterol.

Accepted Answer

The answer of Which of the following food types should...

Question 20

Why is it important to introduce new foods to infants one at a time?
A) Infant digestive systems cannot handle combinations of different foods.
B) Introducing foods one at a time helps to isolate possible food allergies.
C) Infants may develop an aversion to foods that are combined with other foods.
D) Infants may develop an unhealthy appetite for combined foods.

Accepted Answer

Introducing new foods to infants one at a time is crucial for identifying any allergic reactions to specific foods. By isolating foods, parents and caregivers can more easily pinpoint which food may be causing an adverse reaction, such as a rash, gastrointestinal discomfort, or more severe allergic responses. This method does not imply that infants' digestive systems can't handle combinations of foods or that they will develop aversions or unhealthy appetites for combined foods; rather, it's a safety measure to monitor for allergies.

Quiz 4: Infancy: Physical Development

Which of the following is true of myelination?

In the context of infant nutrition, infants _____.

In the context of feeding infants, infant formula is widely considered _______.

The introduction of whole cow's milk to an infant_________.

Which of the following is true of neurons?

Alzheimer's disease is associated with which factor in concerning neuronal functioning?

According to the American Academy of Pediatrics, infants should be fed breast milk _________.

The basic units of the nervous system are cells called _____.

Which of the following foods should not be given to infants until at least the latter part of the first year?

Which of the following statements is true of dendrites?

Messages are released from axon terminals in the form of chemicals called _____.

The high fat content of a myelin sheath insulates a neuron from which components of the fluids that encase the nervous system?

Billy is a four-year-old boy. He has trouble walking and running like other children his age, and he sleeps through most of the day. He is diagnosed with multiple sclerosis. Billy's condition is the result of _____.

Breastfeeding is considered impractical for many women in the United States because of _______.

In the context of neurons, which of the following is a function of the myelin sheath?

An individual develops intellectual disability because of a disorder called phenylketonuria. Which of the following occurrences is a cause of the intellectual disability in the individual?

In the context of introducing solid foods to an infant, which of the following is recommended?

Which of the following is a downside to breastfeeding?

Which of the following food types should infants be allowed to eat plenty of?

Why is it important to introduce new foods to infants one at a time?