Biology - Sexual Reproduction Flashcards
Testis
produces sperms and male sex hormones such as testosterone
Epididymis
stores inactive sperms from the testis before they are released into the sperm ducts
Spermatic cord
supplies blood to the testis
Scrotum (scrotal sac)
pouch-like sacs located outside the body cavity to help maintain a lower temperature for the development of sperms
Sperm duct (vas deference)
the pathway travelled by sperms after they are released from the testis
Seminal vesicle
stores sperms temporarily before they are released through the urethra
Seminal vesicle, prostate gland, and Cowper’s gland
activate sperms by secreting a slippery fluid that contains nutrients and enzymes
The mixture of this fluid and sperms is called semen.
Urethra
a tube that extends from the bladder, through the penis, to outside the body
Both urine and semen exit the body through the urethra, but never at the same time. The sphincter muscles at the base of the urinary bladder prevent urine from exiting the body during ejaculation.
Penis
erectile organ that becomes erect and hard during sexual intercourse in order to enter and deposit semen into the vagina
An erection occurs when the spongy tissue in the penis is filled with blood.
Sperm
Sperms (spermatozoa) are produced throughout the lifetime of a male human after he reaches physical maturity.
Head, middle piece, tail
Head of sperm
a nucleus that carries one haploid set of chromosomes
small amount of cytoplasm
an acrosome that contains enzymes for breaking down part of the egg membrane for sperm penetration
Middle piece of sperm
contains numerous mitochondria that provide energy for sperm to swim to the egg.
Tail of sperm (flagellum)
beats to enable the sperm to swim towards the egg.
Ovary
produces eggs and female sex hormones such as oestrogen and progesterone
Fallopian tube (Oviduct)
a narrow muscular tube with a funnel-like opening at the ovary
Mature eggs are released from the ovary into the oviduct to be fertilised.
Uterus (womb)
the location where the foetus develops; it has elastic muscular walls that enable contraction during birth to expel the foetus
Uterine lining (endometrium)
the soft, smooth inner lining of the uterus that is important for embryo implantation
Cervix
the circular ring of muscle at the lower end of uterus
Vagina (birth canal)
the location where semen is deposited during sexual intercourse; spans the area from the cervix to the vulva (the opening-thing)
Ovum – When are they present? When and how are they released?
Ova (plural, eggs) are present in the ovaries of a female at birth. Eggs are released into the oviducts from the time a female reaches puberty until she reaches 45-55 years of age.
Ovum – structure
The ovum is made up of a:
• large nucleus containing one haploid set of chromosomes,
• large amount of cytoplasm which may contain a small amount of yolk, and
• cell surface membrane that is surrounded by an outer membrane.
Menstrual cycle – definition
The cycle of events that takes place in the female reproductive organs every month
Average length of menstrual cycle? Range?
28 days, with a natural variation of 21-33 days.
Factors that affect menstrual cycle?
Stress, illness, unbalanced diet, and/or malnutrition.
of days – ATM # memorisation technique?
5-5-7-11
5: Menstruation
5: Follicle stage
7: Fertile period
11: Corpus luteum
Menstruation def?
The monthly discharge of blood from the uterus via the vagina
