teenagers think about the offspring with girls
Connections between neurons become stronger and faster during the teenage years.
Unused neurons and neuronal connections are pruned.
you get a lot more mature
waht changes in the chromosomes occur during meiosis
...pressure changes that occur during breathing.
All the secondary sexual characteristics.
They become more flexible and elastic.
The two ways that genetic variations may occur are:Mutations in DNA2. Rearrangement of genes during meiosis
waht changes in the chromosomes occur during meiosis
Physical changes
Puberty is the start of the passage from child to adult. There are all sorts of changes to the body and brain that occur during this time, which can take a few years. There is a lot of growing involved in this procedure so you should notice a bit more meat on your bones by then and weight gain too.
Turns in to a bird
As people age, degenerative changes in the lens's proteins occur.
Tolerance, Addiction, Dependence
There are many non-physical changes that occur during adolescence, most notably the large increase in the number of conections between neurons in the brain. this is what causes the sporadic behaviour in adolescents, and helps the brain and personality to develop by 'trimming' the unnecessary synapses. The flood of hormones (testosterone and oestrogen in men and women respectively) that causes the physical changes also cause a development in the sexuality of the adolescent (it makes the horny).
bogo
Your hormones.
Cellular respiration
Mutation
usally