Human Reproduction -MG Flashcards
What are gametes? And what are the names of the male and female gametes?
It’s a reproductive cell used for the purpose of sexual reproduction. Ovum for females, and spermatozoon for males.
How many chromosomes are in a gamete and how is it different from a typical cell?
A gamete contains half the chromosomes compared to other cells in the body. This means a human gamete has 23 chromosomes (none are in pairs). A typical cell will have 46 chromosomes (23 pairs).
What are the 3 parts of a spermatozoon?
Head, mid piece, and tail
What is fertilization?
When spermatozoon and ovum meet.
What must unite in order to create a new individual?
The gametes (spermatozoa and ova)
How are fraternal twins formed?
Sometimes a woman has two ova the reach maturity and both get released during ovulation. If the two ova both become fertilized, this will result in fraternal twins.
What are fraternal twins?
Twins that do not have the same DNA since they were created from two different ova and two different spermatozoa.
What are identical twins?
Twins who share the same DNA since they were created from the same ovum and spermatozoon.
How are Indental twins formed?
If only one ovum is fertilized but then later splits into two during cell division at the start of pregnancy.
What is a zygote? And how many chromosomes
A single cell with 46 chromosomes (half are from ovum and other half from spermatozoon) that will undergo cell division (mitosis) and pregnancy begins.
What is pregnancy and when does it begin?
Pregnancy is when a woman Carrie’s an embryo (which will later become a fetus) in her uterus. It starts as soon as an ovum is fertilized by a spermatozoon and makes its way to the uterus.
Where is the zygote formed?
Fallopian tube
What is implantation?
Once a ball of 100 cells has been formed, it will attach to the endometrium.
What is an embryo and how’s it formed?
Once implantation occurs, the ball of 100 cells is now called an embryo and will keep its name until the 8th week of pregnancy.
What is a placenta? (And umbilical cord)
Organ that carries nutrients and oxygen from the mother to the fetus through the umbilical cord. It also helps remove wastes.
What is an amniotic sac (and fluid)?
It’s a fluid-filled pouch that surrounds the embryo. The sac is filled with clear, yellow fluid called “amniotic fluid”. They both are important to protect the developing embryo form outside dangers.
What is a fetus and how long is it a fetus?
At a certain point, most of the embryo’s organs have begun to form and the embryo will officially become a fetus. It stays this way from 8-40weeks.
What are the three stages of birth?
Effacement and dilation, expulsion, delivery of the placenta
Describe effacement and dilation. (During birth) and how long it lasts.
During this stage, oxytocin (a hormone) causes uterine contractions and causes the female’s cervix of efface (thin out) and dilate (open). Can last 2-20h. The woman should be 10cm dilated to start giving birth.
Describe expulsion. (During birth) and how long does it last
The uterine contractions become very strong. This causes the baby to move from the uterus through the cervix and into the vagina. As the baby starts to move into the variance, it’s head rotates to help its body pass through the canal more easily. Lasts 30mins-2H.
Describe the delivery of the placenta (during birth) and how long does it last.
Once the baby is born, the umbilical cord will have to be cut so that the placenta will no longer be attached to the baby. Contractions do not yet stop since more contractions are required to detach the placenta from the uterus so the body can expel it. This occurs 10-15mins after the baby is born.
What are the stages of human development before birth?
Zygote, embryo, fetus
What are the stages of human development after birth?
Childhood, adolescence, adulthood
What are the milestones (in order) for childhood?
Infancy, early childhood, childhood
What are the milestones (in order) for adolescence?
There aren’t any. It’s just adolescence.
What are the milestones (in order) for adulthood?
Adulthood, old age
What is puberty and when does it start for both genders?
Puberty is when rapid growth happens and there will be changes in behaviour. Age 10 for girls and 12 for boys.
What does the pituitary gland do during puberty?
It starts to release 2 sex hormones: follicle stimulating hormone (FSH) and luteinizing hormone (LH).
What are the main primary and secondary hormones released during puberty for girls?
Primary: follicle stimulating hormone (FSH) and Luteinizing hormone (LH)
Secondary: progesterone and estrogen
What are the main primary and secondary hormones released during puberty for boys?
Primary: follicle stimulating hormone (FSH) and Luteinizing hormone (LH)
Secondary: testosterone
What is contraception?
Contraception is a method used to prevent pregnancy.
What’s the difference between hormonal and non-hormonal contraceptives?
Hormonal contraceptives contain hormones like estrogen and progesterone, but non-hormonal don’t contain hormones and act as a barrier to spermatozoa or chemically destroy spermatozoa.
What is an STBBI and how do they spread?
They’re sexually transmitted blood-borne infections that can be spread sexually or through contact with blood.
What happens if u do have an STBBI?
You need to receive treatment and tell your partner(s) that you have been diagnosed in order to limit the spread. Partners need to also receive treatment.
How long can spermatozoa survive in the female’s body?
3-5days
How long can an ovum survive?
24h
What are the four parts of the menstrual cycle and the order?
Menstruation, pre-ovulation, ovulation, post-ovulation
What is pre-ovulation?
Endometrium thickens and ovum is maturing
What is ovulation?
Ovum is released from the ovary (always 14 days before the next cycle starts)
What is post-ovulation?
Endometrium continues to thicken in case of pregnancy as ovum makes its way to the uterus.
