chapter 16.4 sexual reproduction in human

what does testis do?

responsible for the production of sperm and testosterone

what does sperm duct do?

conducts sperm from the testes to the prostate gland

what does prostate gland do?

secretes an alkaline fluid to neutralise vaginal acids (to maintain sperm viability)

what does urethra do?

allow a passage of urine and semen from the prostate gland to the outside of the body

what does scrotum do?

is a bag of skin that holds the testes

helps to keep the temperature of testes lower than the average body temperature

what does penis do?

for urination and sexual intercourse

what does ovary do?

responsible for oestrogen and progesterone secretion

what does oviduct do?

is where the fertilisation occurs

what does uterus do?

will be thicken in preparation for implantation of fertilised egg

what does cervix do?

connects the vagina to the uterus

what does vagina do?

is a passage leading to the uterus by which the penis can enter

adaptive features of sperm

1) flagellum - to help it to swim

2) mitochondrion - to release energy

3) acrosome - containing enzymes to digest the jelly oat of the egg

(in the head of the sperm contains haploid - half of chromosomes)

adpative features of egg cell

1) nuclues - contains haploid - half of chromosomes

2) cytoplasm - conatins nutrients for growth of the developing embryo

3) corona radiata - a protective coating around the egg cell

4) zona pellucida (jelly coat) - will be hardened after fertilisation to prevent the entry of other sperms

explain the early development

after fertilisation, zygote is formed

the zygote continues to divide by mitosis to form an embryo (early stage of the baby)

the embryo will then implants into the lining of the uterus

what does the amniotic fluid do?

1) supports the fetus

2) protects the fetus

what does umbilical cord do?

connects the foetus to the placenta

what does placenta do?

1) allows oxygen, dissolved food and antibodies to diffuse from the mother’s blood to the foetus’s blood

2) allows waste of excretory products to diffuse from the foetus’s blood to the mother blood

3) produces oestrogen and progresterone