Lesson 3A - Human Development PDF

Lesson 3 - Human Development Introduction to Psychology  Human Development Behavior from prenatal to later life. Heredity – the transmission of traits from parents to offspring. Chromosomes – a strand like structure found in the nuclei of the cell. (compose of DNA)  Deoxy...

Lesson 3 - Human Development Introduction to Psychology  Human Development Behavior from prenatal to later life. Heredity – the transmission of traits from parents to offspring. Chromosomes – a strand like structure found in the nuclei of the cell. (compose of DNA)  Deoxyribonucleic acid (DNA) – a ladder like structure assembled from smaller molecules (contains thousand of genes). Genes – segment of DNA that serve as a basic unit of heredity.  Reproductive cells Sperm cells Egg cells / ova (ovum) /spermatozoa (spermatozoon) Egg Cell Sperm Cell The egg cells have a nucleus A sperm cell consists of a that is surrounded by head, a mid-piece and a tail. cytoplasm The head contains the Egg cells are produced in nucleus the ovary of a female Sperm cells are produced in human being the testicles of a male Larger compared to sperm human being. cells It is very small in size compared to egg cells Egg Cell Sperm Cell Only a single egg cell is Millions of cells are released produced during once during a single ejaculation. menstruation cycle. Requires approximately two Requires warm body degrees lesser than the temperature for body temperature for sustenance. sustenance. Egg cells are usually formed Sperm cells form during in a female before birth. puberty. Egg Cell Sperm Cell Egg cells have a short life Sperm cells have a longer span. If an egg cell is not life span. Once ejaculated in fertilized 12 to 24 hours the female womb they can after its release from the survive for 3-5 days. ovary, it will dissolve Sperm cells start being Egg cells form before birth produced from the body and are active only till from puberty till death. menopause. Can be frozen and stored. Cannot be stored.  Reproductive Organs Ovaries (gonads) egg cell Testicles /testes (gonads) 23 chromosomes sperm cell 23 chromosomes 46 chromosomes  Ovulation – the release of an egg cell from a females ovary.  Types of Gene Dominant gene - is one whose characteristic will be dominant when paired with another gene. Recessive gene - is one whose characteristics will not be produced when paired with dominant gene. Homozygous - combination (pair) of both dominant genes or both recessive genes. Heterozygous - a pair of dominant and recessive genes.  Father Mother B b B b heterozygous homozygous - Brown eyes B (dominant ) Represents that 75 percent of the offspring - Blue eyes b (recessive ) will have brown eyes  (23rd chromosome) Gonosomes - sex chromosomes Egg cell Sperm cell meiosis x x x x yx y x x x x x y x y x x x x x x y x y x x x girl xx Girl -XX xy Boy - Xy boy  Types of Twin Identical twin monozygotic – single zygote splits into two.  Fraternal twin / dizygotic – two zygotes were developed  Conjoined / Siamese – unfinished split of monozygote.  Multiple birth – 3 or more birth at the same delivery.  Abnormalities Down syndrome / trisomy 21 It is named after John Langdon Down, the British doctor who fully described the syndrome in 1866. Some aspects of the condition were described earlier by Jean-Étienne Dominique Esquirol in 1838 and Édouard Séguin in 1844.The genetic cause of Down syndrome—an extra copy of chromosome 21—was identified by French researchers in 1959.  Abnormalities Fetal alcohol syndrome afp20050715p279-f2  Issues: Test tube baby/ In Vitro fertilization Artificial insemination Artificial insemination is when specially washed semen is directly transferred into a woman's uterus via the cervix. It is an in vivo fertilization — in the body — and not in vitro, in the lab, like IVF.