Human Reproduction Flashcards
What is puberty?
The majority of boys and girls start to feel the effects of sex hormones at the beginning or during their adolescence. Puberty begins when these hormones produce changes in their bodies.
What is the pituitary gland?
At puberty, the pituitary gland (pea sized gland located at the base of the brain) starts to release sex hormones.
What happens to the sex hormones?
The sex hormones travel in the bloodstream until they reach the testicles in males and the ovaries in females.
What is the main male sex hormone?
Testosterone
What are the main female sex hormones?
Estrogen and progesterone
Age where puberty occurs in males ?
Starts between 12 And 16
Age where puberty occurs in females?
Starts between 10 and 14
Name some physical puberty changes in males.
- Develop Adam’s Apple
- Ejaculation
- Pectoral muscle development
- broadening chest and shoulders
- muscle development increases
Name some physical puberty changes in females.
- Menstruation
- Breast Development
- Hips widen
Name some physical puberty changes that occur in both males and females.
- Hair Development
- body odor
- Growth Spurt
- acne
- Perspiration
- voice deepens
- Mood change
- weight change
- genitals become slightly darker
- genitals increase in size
What is the role of sex hormones?
They travel through the bloodstream and signal the testicles (in males) and ovaries (in females) When to begin producing gametes.
Which structure is responsible for releasing the sex hormones?
Pituitary gland.
How do the sex hormones get to the ovaries and testicles?
By travelling through the bloodstream
Scrotum
Pouch that contains the testicles and is located outside the body.
Testes
Contain seminiferous tubules that make the male gametes (Spermatozoa ). Males have two testes.
Epididymis
Elongated pouch located above the testicles that store the Spermatozoa.
Vas Deferens
Tube the Spermatozoa enter to go from the epididymis to the urethra
Prostate gland and seminal vesicle
Both produce a fluid called semen that will mix with the spermatozoa. The semen helps the Spermatozoa move and is rich in sugar.
Urethra
A tube that carries semen (containing spermatozoa) from the vas deferens, out of the body through an opening in the penis called the glans. Urine from the bladder also passes out of the body in this same way.
What is the menstrual cycle?
The menstrual cycle causes changes to the female reproductive organs.
The cycle lasts 28 days.
One ovum reaches maturity during every cycle.
What happens when the ovum reaches maturity?
The body acts as if the ovum was about to be fertilized. The endometrium thickens to help the zygote implant in the uterus and begin its development.
How does a woman’s body temperature change during the menstrual cycle?
A woman’s body temperature increases by about 1°C right before ovulation occurs.
What happens on day 1-5 of the menstrual cycle ?
Menstruation - If the ovum is not fertilized after a few days, it is expelled from the body along with the cells that line the uterus (endometrium).
What happens on day 6-10 of the menstrual cycle?
Follicle development - the lining of the uterus starts to thicken.
What happens during day 11-18 of the menstrual cycle?
Ovulation - Optimum time for fertilization. The ovum is released from the follicle and then the ovaries into the Fallopian tube.
What happens on day 19-28 of the menstrual cycle?
At this time the lining of the uterus continues to thicken. Ovum makes its way to the uterus.
What happens on day 24-28 of the menstrual cycle?
The unfertilized ovum dies and the cycle restarts. (Menstruation begins)
Why does the lining of the uterus thicken during the menstrual cycle?
The lining of the uterus thickens during the menstrual cycle to help the zygote implant in the uterus and begin its development.
When is the best time to have intercourse in order to become pregnant?
A few days before ovulation
When is the time in the menstrual cycle when you have the lowest chance of becoming pregnant?
During menstruation
What is ovulation?
When the ovum is released from the follicle, leaves the ovary and ends up in one of the Fallopian tubes.
What is menstruation?
When the unfertilized ovum is expelled from the body along with the endometrium.
When does the temperature go back down in the menstrual cycle?
Right before menstruation
Describe the life of a spermatozoon from its birth in a testicle to its death in a Fallopian tube .
After the spermatozoon is born in the seminiferous tubules, it is stored in the epididymis. Then through the vas deferens, then past the seminal vesicle and prostate gland. Then into the urethra and out of the opening in the penis called the gland. Then it enters the vagina and fights its way through to the uterus. But then it it faced with a fork in the road: the Fallopian tubes. It chooses a side, not knowing if it’s the one where the ovum is. It waits for 24-48 hours and if it meets no ovum , it dies.
Describe the life of an unfertilized ovum from birth to death.
Ovum is born in follicle, located in ovary. Reaches maturity and the follicle breaks open and ovum is released in Fallopian tube. Waits for a few days in Fallopian tubes. If no spermatozoa come, the ovum is excreted during menstruation along with the endometrium. Through cervix then vagina.
Cowper’s gland
Releases a fluid into the urethra to neutralize the acidity caused by any remaining traces of urine
Ovaries
There are 2 ovaries that take turns releasing an ovum about every 28 days.
Follicles
Each follicle has one ovum. Follicles are located in the ovaries and they bring the ovum to maturity.
Fallopian tubes
Once the ovum has reached maturity it it released by the follicle in the ovary and it travels down the Fallopian tube to reach the uterus.