First Five The chart shows the ages at which the changes associated with puberty take place in boys and girls. What is the most common age at which boys undergo the changes of puberty? If a girl had not started menstruation by the age of 15, would this be cause for concern? Which two features of puberty show the greatest range in the times at which they occur. Is it unusual for a girl of 9 years to start her menstrual periods? On average, is it boys or girls who first show the onset of puberty?

Human Reproduction IGCSE Biology

What is reproduction? It is divided into two main types: Reproduction is the production of new members of a species, replacing those who die due to old age, disease, competition etc. It is divided into two main types: Sexual reproduction involves two parents who have sex organs which produce sex cells. P40 Video Reproduction 1. Introduction (write short note on sex repro, gametes) DRAW labelled sperm and egg cells Key parts for sperm- head with nucleus containing important genetic information Tail to allow sperm to swim towards egg Egg-nucleus containing important genetic information Cytoplasm containing a large food store Asexual reproduction involves one parent and no sex cells

Sexual Reproduction in Humans: Three Stages production of gametes eggs in females sperm in males gametes are haploid: have a single set of chromosomes (DNA) fertilization joining of gametes fusing of the nuclei of the gametes zygote the new, fused cell diploid: has pairs of chromosomes (DNA)

Sex cells Sex cells are called gametes The male gametes are sperm Most animals reproduce sexually so they need: Sex cells Sex cells are called gametes The male gametes are sperm The female gametes are eggs (or ova) The sperm and egg have to meet and a sperm nucleus must fuse (join) with the egg nucleus. This process is called fertilization. A fertilized egg is known as a zygote

Sperm Egg (ovum) Tail which allows it to move Nucleus containing DNA Head- mainly a nucleus containing genetic material (DNA) Tail which allows it to move Nucleus containing DNA Egg (ovum) Cytoplasm with food store, cannot move

ANATOMY: Test What You Know In your current seating arrangement groups, match the scientific vocab to the correct arrow. You will have 2 minutes to make you predictions

Human Reproductive System Male Name Function sperm duct sperm and semen travel along it urethra sperm & urine released through it testes produces sperm & testosterone (male sex hormone) scrotum Sac containing testes – outside the body; Maintains optimum temperature penis for placing sperm into female

Add it on: prostate gland production and secretion of nutrient-rich fluid, fluid joins with sperm to form semen

Human Reproductive System Female Name Function oviduct (fallopian tube) eggs released into it, site of fertilization ovary produces eggs & estrogen (female sex hormone) uterus where fertilized egg implants cervix opening between uterus and vagina vagina sperm deposited here P41 Cut outs C3, C4 Human reproductive system Use this OHP as check on what they’ve filled in

http://www. curriculumbits http://www.curriculumbits.com/prodimages/details/biology/reproductive-organs.html

Review Questions What is the name for the narrow opening between the uterus and the vagina? Where is the prostate gland, and what is its function? Explain how ovulation happens. Where are sperm made? How does an egg travel along the oviduct? Where does fertilization take place?

Quick Class Practice

?1 ?5 ?2 ?4 ?3

?1 seminal vesicle ?7 ?6 ?2 erectile tissue ?3 ?5 ?4

Steps of Fertilization

From Fertilization to Zygote to Implantation

What is fertilization? When the sperm and the egg FUSE together.

Pathway for Fertilization

Fertilization

Path of Zygote

Cleavage of Human Embryo

From Fertilization to Implantation After fertilization, the embryo travels through the oviduct, into the uterus. The embryo will implant in the wall of the uterus.

Implantation

Implantation and After Two key events after implantation of the embryo in the uterine wall are: Differentiation of cells Development of the placenta and amnion

Cellular Differentiation The changing of unspecialized embryonic cells into the specialized cells, tissues and organs of a multicellular animal

Cellular Differentiation

Number the Stages in the Table What happens? The ZYGOTE reproduces to make a ball of cells called an EMBRYO. The EMBRYO develops into a fetus (an unborn baby). The egg is release from the ovary into the fallopian tube The sperm and egg join together. This is called fertilisation and it makes a ZYGOTE. The EMBRYO travels into the uterus and implants in the lining.

Check your answers to the table

Sperm and egg What do each of these have Sperm and egg What do each of these have? A nucleus which contains the chromosomes (DNA) The nucleus contains the chromosomes which carry your DNA.

What is fertilization? ½ Chromosomes EGG CELL ½ Chromosomes SPERM CELL Full set Chromosomes ZYGOTE

What happens to the zygote? After fertilization the zygote continues to move down the fallopian tube/oviduct to the uterus

What is fertilization? The fertilised egg (Zygote) Then divides and copies itself several times. It then becomes a ball of cells called an embryo.

Passing on instructions Use the keywords to identify the key stages on the worksheet.

After Fertilization: Lining of womb/uterus thickens ready to receive the embryo

After Fertilization: Implantation Embryo attaches itself to the uterus wall. This is called IMPLANTATION.