Chapter 16: Human Sexual Reproductive System Flashcards
What is ‘sexual reproduction’?
It is when the nuclei of two sex cells, an egg cell and a sperm cell, fuse together.
What is fertilization?
The fusion of sex cells.
What happens when an egg cell is fertilised?
It develops into an embryo
What is heredity?
The passing down of genetic material from one generation to the next during sexual reproduction.
How does the mixing of traits in individuals happen?
During sexual reproduction, the individual that is formed receives genetic material from the mother via an egg and from the father via a sperm.
Why can offspring inherit any possible combination of traits from its parents?
Offspring inherits genetic mater from the egg’s nucleus and the sperm’s nucleus, in a unique combination.
What are examples of inheritable diseases?
Sickle cell anaemia and cystic fibrosis
When does the body start to develop into an adult?
Teenage years, 11-14
During puberty, what changes does the body go through?
Physically and sexually
What causes puberty to begin?
When certain hormones are produced by the body
What are hormones?
Chemicals produced by different parts of the body.
What do hormones do?
They control and coordinate activities throughout the body by triggering other organs to function.
Are hormones found in large quantities in the blood or small quantities?
Small
What are the changes that men go through during puberty?
- Height and weight increases
- Voice deepens
- Facial hair, armpit hair and pubic hair appear
- Muscle strength increases
- Production of sperm begins.
What are the changes that females go through during puberty?
- Height and weight increases
- Breasts start to develop
- Hips become broader and rounders
- Armpit hair and pubic hair appear
- Maturation of eggs begin
What are the different parts of the male reproductive system?
- Sex glands
- Sperm duct
- Urethra
- Testis
- Penis
What is the function of the sex glands?
Produces nutrient fluid (semen) do nourish sperm.
What is the function of the sperm duct?
Carries sperm from the testis to the urethra.
What is the function of the urethra?
- A tube that allows sperm to pass through during ejaculation.
- Allows urine to be removed from the body
What is the function of the testis?
- It produces sperm
- It produces male sex hormones
What is the function of the penis?
Deposits semen into the vagina during ejaculation.
What are the different parts of the female reproductive system?
- Oviduct
- Ovary
- Uterus
- Cervix
- Vagina
What is the function of the oviduct?
- A tube where an egg is released from the ovary.
- Fertillisation usually takes place here
What is the function of the ovary?
- Produces eggs
- Produces female sex hormones
What is the function of the uterus?
- A muscular organ where the embryo develops into a foetus during pregnancy.
- Contains uterine lining, which thickens to prepare for implantation and breaks down when no fertillisation occurs
What is the function of the cervix?
- Opening of the uterus
- Connects the uterus to the vagina
What is the function of the vagina?
Sperms are deposited here.
Describe the process of fertilisation.
- The penis deposits the semen containing sperm cells inside the vagina.
- The sperm cells swim through the cervix, into the uterus and into the oviduct.
- A sperm cell meet an egg cell in the oviduct.
- Fertilisation occurs when the nucleus of the sperm cell fuses with nucleus of the egg cell. All other sperm cells die.
What does a fertilized egg develop into?
Embryo
Where does the embryo go to after fertilisation?
It travels down the oviduct towards the uterus, where it is then implanted in the wall of the uterus, where it develops into foetus.
What can cause fertillisation to not take place?
If one of the reproductive systems does not function well, fertilization will be affected.
What are examples for each reproductive system if they are faulty?
Male: Testes cannot produce healthy sperm
Female: Oviduct blocked, sperm cannot meet egg for fertilization to occur.
What are some factors that can affect reproductive systems?
Age, diet, lifestyle
Once puberty begins, what do the ovaries do?
The two ovaries take turns to release an egg cell in about 28 days in preparation for fertilization. At the same time, the uterine lining thickens, with many blood vessels formed, to receive a fertilized egg.
What is menstruation?
When fertilization of an egg doesn’t occur, the lining of the uterus and the blood vessels break down and are discharged through the vagina with the unfertilized egg
What happens from Day 1 to Day 5 of the menstrual cycle?
Menstruation occurs.
What happens from Day 6 to 9 of the menstrual cycle?
The uterine lining thickens, forming many blood vessels. This process prepares the uterus for the implantation of the embryo if fertilization occurs.
What happens from Day 10 to 15?
Ovulation occurs. One ovary will release an egg into the oviduct on around Day 14. This is when a woman is most fertile.
What happens from Day 16 to 28?
The uterine lining continues to thicken. If no fertilization occurs, menstruation will occur again after Day 28.
What are examples of substance abuse?
Smoking, consumption of alcohol and abuse of controlled drugs like heroin and cannabis are examples of substance abuse.
What are the effects of substance abuse on foetus?
- Babies may be born premature.
- Babies may be born with low body weight
- It may affect the development of the foetus’ heart, lungs and brain.
- Babies may develop respiratory problems later in life.
- They are more likely to face obesity or diabetes.
- Physical, intellectual and behavioural challenges in the child.
Why is a premature baby bad?
They require intensive care as their organs may not be fully developed
Why are babies with a low birth weight bad?
They may have underdeveloped immune systems and a higher risk of getting infections
