Chapter 9 (Reproduction in humans) Flashcards
- What is reproduction?
Reproduction is the production of more organisms of the same species.
- What are different types of reproductions and what are their differences?
Sexual reproduction
- produce gametes
- fertilization occurs
- Offspring produce have variations
Asexual reproduction
- non gametes involved
- no fertilization occurs
- clones of the adult organism produced
- What is fertilization?
When the sperm move to the egg and fuse with it.
- What does fertilization form?
Single cell zygote
- How asexual reproduction occur?
Where cells in one part of adult’s body are divided by mitosis in order to form a structure that breaks away from the parent body and grows into a new organism.
- Individuals produced asexually from the same adult organism are called _____.
clones
- Why offspring produced by asexual reproduction are genetically identical as their adult organisms?
Because all the cells of the new individual are produced by mitosis from just one cell of the adult’s body.
- In which condition, asexual reproduction is useful?
Relatively stable condition
- What are fours stages of sexual reproduction?
- Gametes are produced
- Sperm is transferred to the egg cell
- Fertilization occur
- Zygote formed
- Where do gametes produce in the body?
Sperms - testes
Eggs - ovaries
- What are the names of the cells -
- That have the full number of chromosomes
- That have half the normal number of chromosomes
Diploid cells | Haploid cells
- What is external and internal fertilization take place?
External fertilization - outside the body
Internal fertilization - inside the female’s body
- What happen when the sperm reach the egg?
Its nucleus enter the egg and fuse with the egg nucleus.
- How many chromosomes does sperm and egg contain?
23
- Why sperms and eggs are all genetically different?
Because they are formed by meiosis.
- How many chromosomes does red blood cells have?
Zero since they don’t have nucleus.
- What are the only cells that are divided by meiosis?
Gametes
- What does zygote developed into?
Embryo
What is the name of the mixture of seminal vesicles and sperm called?
Seman
How is the semen ejaculated?
It is ejaculated through the urethra into the vagina of the female.
What is ovulation?
Ovulation is where a matured egg is released into an oviduct from one of the ovaries each month.
Why does embryo develop a placenta?
- Placenta will allow the embryo to obtain materials such as oxygen and nutrients from the mother’s blood.
- It also allows embryo to get rid of waste products such as urea and carbon dioxide.
What does placenta secrete?
Progesterone
What enclose the developing embryo during pregnancy?
amnion
What does amnion secrete and why?
amniotic fluid which (cushion the developing embryo) and protect it against sudden movements and bumps.
What does an embryo develop into?
Fetus
What are stages to the birth of a child?
- Dilation of the cervix
- Delivery of the baby
- Delivery of the afterbirth
What happen to cervix to allow the baby to pass through?
It gets wider
What does strong contraction of uterus muscles do?
It tears the amnion allowing amniotic fluid to escape.
What push to baby to the outside world through cervix and vagina?
Strong contractions of the muscles of the uterus.
What happen after the baby has ben born?
The uterus continues to contract and pushes the placenta with the membranes that surrounded the baby.
What is primary sex characteristics?
The presence of male or female sex organs.
What are 2 developments of puberty?
- Gametes start to mature and be released
- Bodies of both sexes adapt to allow reproduction to take place
How does puberty start by?
- Follicle stimulating hormone
- Luteinizing hormone
What does FSH stimulate in boys?
It stimulates the sperm production.
What are changes happened at puberty?
In boys
- Sperm production starts
- Growth and development of male sexual organs
- Growth of armpit and pubic hair, and chest and facial hair
- Increase in body mass
- Voice breaks
- Sexual drive develops
In girls
- The menstrual began and eggs are released by ovaries each month
- Growth and development of female sexual organs
- Growth of armpit and pubic hair
- Increase in body mass; development of rounded shape to hips
- Voice deepens without sudden braking
- Sexual drive develops
- Breasts develop
What event is in the middle of the menstrual cycle?
ovulation (release of mature egg cell)
What is one function of menstrual cycle?
To control the development of the lining of the uterus.
What will happen if the egg is not fertilized?
The lining of the uterus is lost from the woman’s body as the flow of menstrual blood and cells of the lining, called period.
What does egg cells develop into?
Follicle
What is the function of FSH?
- Stimulate the growth of follicle
- Stimulate the release of oestrogen
What is the function of oestrogen?
- Thicken the uterine lining
- Reduce the release of FSH
- Stimulate the release of LH
What is the function of LH?
- For ovulation
What is the function of progesterone?
- Maintain the thickness of uterine lining
What does the remaining of follicle form after fertilization?
corpus luteum
What does corpus luteum produce?
progesterone
When does corpus luteum carry on or stop producing progesterone?
When the egg is not fertilized, the corpus luteum break down and stop producing progesterone.
What is a sign of woman that tell that she is pregnant?
Her monthly periods stop.
Which secretes progesterone later on in the pregnancy?
The placenta
