5.1.1 Development Of The Brain 2

Question 1

A program mechanism of cell death is called ____. It is distinct from necrosis, which is death caused by an injury or a toxic substance.

Answer 1

apoptosis

Question 2

The brains system of over producing neurons and then applying apoptosis enables the CNS to ____ the number of incoming axons to the number of receiving cells.

Answer 2

match

Question 3

When the sympathetic nervous system begins sending axons toward the muscles and glands, it doesn’t know the exact size of the muscles or glands. It makes ____ neurons than necessary and discards the excess.

Answer 3

more

Question 4

The new growth factor is a ____, meaning a chemical that promotes the survival and activity of neurons.

Answer 4

neurotrophin

Question 5

In addition to NGF, the nervous system responds to ____ ____ ____ ____ (BDNF) and several other neurotrophins.

Answer 5

brain derived neurotrophic factor

Question 6

Neurotrophins are not necessary for survival of brain neurons, but they are ____ for growth of axons and dendrites, formation of new synapses, and learning.

Answer 6

essential

Question 7

The early stages of brain development are ____. A mutation in one identified gene needs to any of a wide variety of defects in brain development.

Answer 7

critical

Question 8

The developing brain is also highly vulnerable to ____, ____ ____, and ____ that would produce only mild problems at later ages.

Answer 8

malnutrition, toxic chemicals, and infections

Question 9

The infant brain is highly vulnerable to damage by ____.

Answer 9

Alcohol

Question 10

Children of mothers to drink heavily during pregnancy are born with ____ ____ ____, a condition marked by hyperactivity, impulsiveness, difficulty maintaining attention, varying degrees of mental retardation, motor problems, heart defects, and facial abnormalities.

Answer 10

fetal alcohol syndrome

Question 11

Even in milder cases of fetal alcohol syndrome those were exposed to ____ alcohol show impairments in learning, memory, language, and attention.

Answer 11

prenatal

Question 12

Alcohol suppresses of the release of ____, the brains main excitatory transmitter, and enhances activity of ____, the main inhibitory transmitter. Consequently, many neurons received less excitation and neurotrophins than normal, and they undergo apoptosis.

Answer 12

glutamate : GABA

Question 13

Prenatal exposure to other substances can be dangerous too. On average, children of mothers to use cocaine or smoke cigarettes during pregnancy have an increased risk of ____ ____ and other behavioural deficits.

Answer 13

attention-deficit disorder

Question 14

Children whose mother used antidepressants during pregnancy have increased risk of ____ ____.

Answer 14

heart problems

Question 15

Finally, the immature brain is highly responsive to influences from the mother. ____ to the mother changes her behaviour in ways to change her offsprings behaviour. Children of impoverished and abused woman have, on average, increased problems in both the academic and social lives.

Answer 15

Stress

Question 16

Neurons in different brain areas differ in ____ and ____.

Answer 16

shape and chemistry

Question 17

Immature neurons experimentally ____ from one part of the developing cortex to another develop properties characteristic of the new location. However, neurons transplanted at a slightly later stage develop some new properties while retaining some old ones.

Answer 17

transplanted

Question 18

Our brains have the ability to ____ themselves (with limits) in response to our experience.

Answer 18

remodel

Question 19

Decades ago, researchers doubted that adult neurons substantially changed their shape. We now know that axons and dendrites continue to modify their structure ____ life.

Answer 19

throughout

Question 20

We might suppose that neuronal changes in an enriched environment depend on new and interesting experiences, and many of them do. For example, after practice of particular skills, the connections relevant to those skills ____, while other connections retract.

Answer 20

proliferate

Question 21

Much of the enhancement produced by enriched environment is due to ____ ____. Activity also improves learning and memory.

Answer 21

physical activity

Question 22

Educators have long operated on the assumption that training children to do something difficult will enhance their intellect in general. The idea is to teach one thing and hope students get smarter than other ways too. This is called ___ ____.

Answer 22

far transfer

Question 23

In general, far transfer is weak and hard to demonstrate. ____ ____ is training on one task and finding improvement on a very similar task.

Answer 23

Near transfer

Question 24

One of the best-documented ways to maintain intellectual vigour in old age is the same thing that worked so well for laboratory animals – ____ ____.

Answer 24

physical activity

Question 25

Being blind does not change the touch receptors in the fingers or the receptors in the ears. However, it increases attention to touch and sound, and the brain ____ to that attention.

Answer 25

adapts

Question 26

Investigators asked sighted and blind people to feel the difference between two braille objects. On average, ____ people performed more accurately then ____ people, as you would guess.

Answer 26

blind : sighted

Question 27

PET and fMRI scans indicated substantial activity in the ____ cortex of the blind people while they perform these tasks.

Answer 27

occipital

Question 28

In people blind since birth or early childhood, auditory stimuli also produced increased responses in what we usually ____ areas of the cortex.

Answer 28

visual

Question 29

In short, blind people, unlike sighted people, use the occipital cortex to help identify what they ____.

Answer 29

feel