Body
Story
Brave
new world: First yearSSight
and sp
• Conception
• Month
1
•
Month 2
• Month
3
•
Month 4
•
Month 5
•
Month 6
•
Month 7
• Month
8
•
Month 9
• Birth
to 1 month old
• 1–3
months old
• 4–7
months old
• 8–12
months old
•
Conception
When a sperm penetrates the outer covering of the ovum, it
travels through the cytoplasm and fuses with the nucleus of the cell,
forming a zygote. This is the moment of fertilisation. During the days
after fertilisation, the zygote divides into two cells, then four, and
so on, until it becomes a ball of cells: an embryo. It then travels along
the fallopian tubes to the uterus (womb) where it sinks into the lining
of the uterus wall. This is were it will grow.
•
Month 1
A
dark mark appears on the embryo, indicating the position of a spinal cord.
A rudimentary
heart develops and begins to beat. All the major organs begin to develop
as early as the third week of pregnancy.
•
Month 2
The body begins to elongate, though the head remains disproportionately
large.
The face
begins to develop: eyes are pigmented; nostrils, lips and ears, as well
as fingers and toes, become visible.
•
Month 3
At this point, the embryo becomes known as a foetus. During the third
month, the foetus more than triples in length, while its weight increases
by 16 times. Movement begins: the foetus can turn its head, purse its
lips and hiccup.
Tooth buds
appear in the jaw, and a definite chin, nose and forehead develop. The
ears, which have appeared as gill-like growths on the neck, move up the
side of the head.
A more baby-like
body structure develops: the trunk of the body straightens, and ribs and
bone tissue appear, though in the form of flexible cartilage. External
sex organs start to grow.
•
Month 4
The foetus's senses begin to develop. Although its eyelids are formed
fused shut, it is nonetheless sensitive to light. It also begins to hear
sounds.
The foetus
swallows amniotic fluid and excretes it as urine. It receives oxygen from
the placenta.
Fat begins
to develop, allowing the foetus to conserve heat. Eyebrows also start
to grow, and the fine hair on the head starts to coarsen.
•
Month 5
Sensory development continues apace. The foetus can now distinguish between
sweet and bitter, it is sensitive to touch and its hearing becomes more
acute.
Fat deposits
build up, and sebaceous glands produce a waxy substance to protect the
skin and keep it supple.
Crucially,
the foetus develops its own, very primitive immune system. A sheath forms
around the nerves in the spinal cord to protect it.
The sex organs
develop: the male scrotum becomes solid, while the female foetus's ovaries
already contain ova in preparation for the day when she will become sexually
active.
•
Month 6
The head of the foetus is now growing more slowly than its body, redressing
the balance. The body's shape becomes increasingly childlike, with bone
beginning to harden and muscles developing in the arms and legs. Muscles
allow the foetus to make breathing motions.
The brain
cells used for conscious thought begin to mature. The brainwave patterns
of a six-month-old foetus resemble those of a newborn. The foetus can
distinguish its parents' voices and respond to music.
•
Month 7
Nerve circuits within the brain are now fully active and the nerve fibres
are encased in a fatty sheath for protection.
Fat builds
up under the skin, smoothing out the wrinkles and making the foetus appear
plumper. It is beginning to fill the amniotic sac, inside the uterus,
and its movement becomes restricted.
Special cells
line the surface of the lungs. These secrete a surfactant — a substance
that reduces surface tension — which ensures they will not collapse
when the newborn begins to use them. The bone marrow produces red blood
cells.
The eyelids
open, and the foetus can practise seeing and focusing.
A baby born
at the end of the seven-month period (around 28 weeks) usually has a good
chance of surviving.
•
Month 8
The internal organs are almost fully developed. The face is also fully
human: the irises can contract and dilate; the eyes can blink and focus.
Many foetuses
'engage' — turn their heads downwards in anticipation of delivery
— at this point, though others may do it later.
•
Month 9
The foetus sheds the fine hair that covers its body. This, along with
pigment, secretions from the alimentary glands and cells from the bowel
walls form a substance called meconium. Meconium fills the intestine,
and will be the first substance that the baby excretes, either during
or after birth.
Last-minute
preparations for breathing are made: cortisone, a hormone, is produced
to help the lungs to mature.
•
Birth to 1 month old
The rate at which babies develop varies enormously, but there are certain
benchmarks that most reach within the first 12 months of their lives.
As the first
month progresses, they become increasingly alert. They move around more,
making jerky movements with their arms. Although their vision is still
very poor, they will watch you when you are close by and listen to sounds.
•
1–3 months old
Babies become alert and responsive. They may start to smile: a reflex
action that they will continue to perform because it produces parental
attention. They will begin to reach, grasp and kick and can follow a moving
object with their eyes.
•
4–7 months old
Vision, touch and hearing become co-ordinated. Motor skills improve. By
seven months, most babies can sit up and roll over. They begin to babble
and enjoy social interaction. They can respond to their names.
•
8–12 months old
Babies become increasingly mobile. Most will crawl and a few will walk,
usually while holding on to something. Babies begin to explore the uses
of objects: shaking, banging and dropping them to see what happens. They
may begin to use objects properly — drinking from a cup, for example.
They begin to respond to verbal commands, such as 'yes' and 'no', and
may begin to say words such as 'mamma'.
Sight
and speech | Primitive
brain | First
year
Born
stupid
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new world
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