Developmental psychology: Changing man
Problem 1 Cell division is the process by which a parent cell divides into two or more daughter cells
Definitions:
✓ Genotype: genetic material of a person
✓ Phenotype: observable traits of genes; The observable
physical or biochemical characteristics of an
organism, as determined by both genetic makeup and
environmental influences
✓ Chromosomes: structure made up of DNA (1 from
ovum one from sperm)
✓ DNA: long double stranded molecule that can duplicate itself (mitosis) Life molecule
✓ DNA replication: biological process of producing two identical replicas of DNA from one
original DNA molecule.
✓ Crossing-over: in meiosis Prophase 1, exchange of genetic material between non-sister
chromatids. 2 homologous(same size) chromatids break at same point, twist around each
other, connect to other’s initial position
-allows DNA from maternal chromosomes to mix with paternal chromosomes, so
recombinant chromatids are mix of both parents
-promotes genetic variation
✓ Alleles: each form of gene (there are 2 forms of each gene, one from mom and other from
father at the same place) dominant → the allele that always influences the phenotype;
recessive → has to be present twice to be expressed; co-dominant → two alleles expressed
together
✓ Somatic cells: body cells
✓ Gene expression: genes influence the physical and psychological development
✓ Gene Locus: a specific and fixed position of the gene on the chromosome
✓ Epigenetics: study of how and when are genes expressed (talked a lot about this in lecture:
how nutrition influences babies)
✓ Gametes: reproductive cells or sex cells that unite during sexual reproduction to form a
new cell called a zygote. Male gametes: sperm and female gametes: ova (eggs) Gametes
are formed through meiosis
Chromosomes (gene location)
• Humans:23 pair of chromosomes
• Autosomal chromosomes: matched pair chromosomes;
contain genes that are responsible for the determination of
somatic characteristics (22)
, • Sex chromosome (X&Y): no matched pair; contain
genes that determine sex and sex related
characteristics¸consist of one pair of the total of 23
pairs of chromosome
• DNA consists of: repeating units called nucleotides (proteins)
o A,G, T, C. (adenine, guanine, thiamine, cytosine- sugar and phosphates)
o A goes with T and C goes with G
Mutatation:
o Accidental alterations in individual nucleotide sequence,
usually mutatations dissapear over generations
o Some are beneficial: sickle cell anemia provents people
from
malaria
o Sudden but
permanent change in
a segment of DNA
MITOSIS VS MEIOSIS
Mitosis:
o Chromosomes
duplicate
themselves before
divisions=> 2 new cells with
identical pairs of chromosomes
(each chromosome splits
lenghtwise)
o Somatic cells that are devided by
mitosis form muscles, bones,
organs (important to grow new
cells)
Meiosis:
o Homologous chromosome pair:
contains versions of the same
gene/alleles on the same spot for a given trait
o Independent assortment: each pair of chromosomes segregates independently
of all other chromosome pairs during meiosis
Males 4 sperms and female one ovum; when sperm and egg unite they build a cell with full set of 46
chromosomes (total of 23 pairs)
, Meiosis I begins with one diploid parent cell and ends with two haploid daughter cells, halving the number of
chromosomes in each cell.
Meiosis II starts with two haploid parent cells and ends with four haploid daughter cells, maintaining the
number of chromosomes in each cell.
GENES- made from DNA, Basic unit of heredity
Genetic inheritance
• Dichotomous traits: (brown or white peas) organism either has or it does not have
trait
• True breading lines: breeding lines in which interbred members
always produce offspring with the same trait (e.g. brown peas)
generation after generations. True breeding occurs in nature
when a particular trait is crucial for survival in a certain
and therefore it outweighs the genetic environment
variability cost of losing
INHERITANCE
Simple dominant- Recessive inheritance:Each trait has 2 alleles: one dominant one recessive
Codominance:
One allele is not dominant over the other
Incomplete dominance: one is more dominant but fails to being more dominant over the other(not possible with
blood types)
Sex-linked inheritance:
, All sex- linked traits are controlled by genes on
the X chromosome bc Y is small and Carries few
genes
If trait= dominant, females inherit it bc they have
2Xs
• Females can be carriers males cant but can
have conditions
Polygenic inheritance:
Traits are influenced by many
pairs of alleles
They show normal db in
population few falling in
extremes and most falling
somewhere in the middle
MENDELS LAW:
Simple dominant/recessive
• experiment with Pea Plants: cross breeding peas, predict outcome of offspring based on dominant
and recessive traits
• Results: found different variations of dominant and recessive alleles, have different outcomes
with different pairs
Sources of variability in the offspring:
HEREDITARY DISORDERS
• Crossing-over
• Random orientation
• Random sperm meeting with
CHROMOSOMAL ABNORMALITIES:
the ovum
-During meiosis 46 chromosomes devide unevenly
-One gamete has too many chromosomes wheras other has
too little
• Turner syndrome: XO(misses a second X). Females have less spatial abilities,
problems developing secondary sex organs. (sex.linked chromosomal)
• Kleinerfelters disease: XXY; infertile male, underdeveloped testes. Secondary female
characteristics. Male primary characteristics. (sex-linked chromosoma)(cant have
children)
• Supermale: XYY; taller and bigger. 20 to 30% have some intellectual impairment
• Superfemale: XXX; impaired IQ, taller than
usual girls, usually normal sexual
development, menstruaal irregularities
• Fragile X: mental retardation
AUTOSOMAL
ABNORMALITIES:
Problem 1 Cell division is the process by which a parent cell divides into two or more daughter cells
Definitions:
✓ Genotype: genetic material of a person
✓ Phenotype: observable traits of genes; The observable
physical or biochemical characteristics of an
organism, as determined by both genetic makeup and
environmental influences
✓ Chromosomes: structure made up of DNA (1 from
ovum one from sperm)
✓ DNA: long double stranded molecule that can duplicate itself (mitosis) Life molecule
✓ DNA replication: biological process of producing two identical replicas of DNA from one
original DNA molecule.
✓ Crossing-over: in meiosis Prophase 1, exchange of genetic material between non-sister
chromatids. 2 homologous(same size) chromatids break at same point, twist around each
other, connect to other’s initial position
-allows DNA from maternal chromosomes to mix with paternal chromosomes, so
recombinant chromatids are mix of both parents
-promotes genetic variation
✓ Alleles: each form of gene (there are 2 forms of each gene, one from mom and other from
father at the same place) dominant → the allele that always influences the phenotype;
recessive → has to be present twice to be expressed; co-dominant → two alleles expressed
together
✓ Somatic cells: body cells
✓ Gene expression: genes influence the physical and psychological development
✓ Gene Locus: a specific and fixed position of the gene on the chromosome
✓ Epigenetics: study of how and when are genes expressed (talked a lot about this in lecture:
how nutrition influences babies)
✓ Gametes: reproductive cells or sex cells that unite during sexual reproduction to form a
new cell called a zygote. Male gametes: sperm and female gametes: ova (eggs) Gametes
are formed through meiosis
Chromosomes (gene location)
• Humans:23 pair of chromosomes
• Autosomal chromosomes: matched pair chromosomes;
contain genes that are responsible for the determination of
somatic characteristics (22)
, • Sex chromosome (X&Y): no matched pair; contain
genes that determine sex and sex related
characteristics¸consist of one pair of the total of 23
pairs of chromosome
• DNA consists of: repeating units called nucleotides (proteins)
o A,G, T, C. (adenine, guanine, thiamine, cytosine- sugar and phosphates)
o A goes with T and C goes with G
Mutatation:
o Accidental alterations in individual nucleotide sequence,
usually mutatations dissapear over generations
o Some are beneficial: sickle cell anemia provents people
from
malaria
o Sudden but
permanent change in
a segment of DNA
MITOSIS VS MEIOSIS
Mitosis:
o Chromosomes
duplicate
themselves before
divisions=> 2 new cells with
identical pairs of chromosomes
(each chromosome splits
lenghtwise)
o Somatic cells that are devided by
mitosis form muscles, bones,
organs (important to grow new
cells)
Meiosis:
o Homologous chromosome pair:
contains versions of the same
gene/alleles on the same spot for a given trait
o Independent assortment: each pair of chromosomes segregates independently
of all other chromosome pairs during meiosis
Males 4 sperms and female one ovum; when sperm and egg unite they build a cell with full set of 46
chromosomes (total of 23 pairs)
, Meiosis I begins with one diploid parent cell and ends with two haploid daughter cells, halving the number of
chromosomes in each cell.
Meiosis II starts with two haploid parent cells and ends with four haploid daughter cells, maintaining the
number of chromosomes in each cell.
GENES- made from DNA, Basic unit of heredity
Genetic inheritance
• Dichotomous traits: (brown or white peas) organism either has or it does not have
trait
• True breading lines: breeding lines in which interbred members
always produce offspring with the same trait (e.g. brown peas)
generation after generations. True breeding occurs in nature
when a particular trait is crucial for survival in a certain
and therefore it outweighs the genetic environment
variability cost of losing
INHERITANCE
Simple dominant- Recessive inheritance:Each trait has 2 alleles: one dominant one recessive
Codominance:
One allele is not dominant over the other
Incomplete dominance: one is more dominant but fails to being more dominant over the other(not possible with
blood types)
Sex-linked inheritance:
, All sex- linked traits are controlled by genes on
the X chromosome bc Y is small and Carries few
genes
If trait= dominant, females inherit it bc they have
2Xs
• Females can be carriers males cant but can
have conditions
Polygenic inheritance:
Traits are influenced by many
pairs of alleles
They show normal db in
population few falling in
extremes and most falling
somewhere in the middle
MENDELS LAW:
Simple dominant/recessive
• experiment with Pea Plants: cross breeding peas, predict outcome of offspring based on dominant
and recessive traits
• Results: found different variations of dominant and recessive alleles, have different outcomes
with different pairs
Sources of variability in the offspring:
HEREDITARY DISORDERS
• Crossing-over
• Random orientation
• Random sperm meeting with
CHROMOSOMAL ABNORMALITIES:
the ovum
-During meiosis 46 chromosomes devide unevenly
-One gamete has too many chromosomes wheras other has
too little
• Turner syndrome: XO(misses a second X). Females have less spatial abilities,
problems developing secondary sex organs. (sex.linked chromosomal)
• Kleinerfelters disease: XXY; infertile male, underdeveloped testes. Secondary female
characteristics. Male primary characteristics. (sex-linked chromosoma)(cant have
children)
• Supermale: XYY; taller and bigger. 20 to 30% have some intellectual impairment
• Superfemale: XXX; impaired IQ, taller than
usual girls, usually normal sexual
development, menstruaal irregularities
• Fragile X: mental retardation
AUTOSOMAL
ABNORMALITIES:
