Problem 1 – The birds and the bees
Developmental psychology
The process of genetic transmission
Chromosomes and genes are located in the cell’s nucleus
Chromosomes- thread-like structures in the cells nucleus that carry genetic
information to help direct development
Most cells contain 46 chromosomes
Sex cells contain 23 chromosomes
DNA is duplicated by free nucleotides bonding to broken down bases
DNA bases- A,T,C,G
DNA- a ladder like molecule that stores genetic information in cells and transmits it
during reproduction
Nucleotide- a compound containing a nitrogen base, a simple sugar and a phosphate
group
Gene- a portion of DNA located at a particular site on a chromosome that codes for
the production of certain kinds of proteins
Autosomes- the 22 pairs of non-sex chromosomes
Sex-chromosomes- the 23rd pair of chromosomes which determine the individual’s
sex and are responsible for sex-related characteristics
Meiosis and mitosis
Meiosis- the process by which a cell divides to produce new reproductive cells with
only half the normal complement of chromosomes
- Male and female reproductive cells contain only 23 pairs of chromosomes
- A cell with only 23 chromosomes is called a haploid cell
- When the cells unite, a new organism will form with the normal 46 chromosomes
(half from each parent)
- Halving process- just before crossing over where the cell spits and randomly
assigns different chromosomes to each of their daughter cells
- Crossing over- the process by which equivalent sections of homologous
chromosomes switch places randomly, shuffling the genetic information
Mitosis- the process by which a body cell divides into two, first duplicating its
chromosomes so that the new daughter cells produces each contain the usual 46
chromosomes.
- A cell with 46 chromosomes is called a diploid cell
- Somatic cell division
Inheritance and gene expression
Developmental psychology
The process of genetic transmission
Chromosomes and genes are located in the cell’s nucleus
Chromosomes- thread-like structures in the cells nucleus that carry genetic
information to help direct development
Most cells contain 46 chromosomes
Sex cells contain 23 chromosomes
DNA is duplicated by free nucleotides bonding to broken down bases
DNA bases- A,T,C,G
DNA- a ladder like molecule that stores genetic information in cells and transmits it
during reproduction
Nucleotide- a compound containing a nitrogen base, a simple sugar and a phosphate
group
Gene- a portion of DNA located at a particular site on a chromosome that codes for
the production of certain kinds of proteins
Autosomes- the 22 pairs of non-sex chromosomes
Sex-chromosomes- the 23rd pair of chromosomes which determine the individual’s
sex and are responsible for sex-related characteristics
Meiosis and mitosis
Meiosis- the process by which a cell divides to produce new reproductive cells with
only half the normal complement of chromosomes
- Male and female reproductive cells contain only 23 pairs of chromosomes
- A cell with only 23 chromosomes is called a haploid cell
- When the cells unite, a new organism will form with the normal 46 chromosomes
(half from each parent)
- Halving process- just before crossing over where the cell spits and randomly
assigns different chromosomes to each of their daughter cells
- Crossing over- the process by which equivalent sections of homologous
chromosomes switch places randomly, shuffling the genetic information
Mitosis- the process by which a body cell divides into two, first duplicating its
chromosomes so that the new daughter cells produces each contain the usual 46
chromosomes.
- A cell with 46 chromosomes is called a diploid cell
- Somatic cell division
Inheritance and gene expression
