Chapter 41 - Human Reproduction Flashcards
Gonad
An organ that produces sex cells in animals
Semen
A fluid containing sperm and seminal fluid
Puberty
The beginning of sexual maturity
Secondary sexual characteristics
Features that distinguish males from females, apart from the sex organs themselves
Infertility
The inability to produce offspring
Ovulation
The release of an egg from the ovary
Menstrual cycle
A series of events that occurs every 28 days on average in the female if fertilisation has not taken place
Menopause
When ovulation and menstruation stop happening in a female
Menstruation
The discharge of the lining of the uterus and the unfertilised egg
Secondary female characteristics
Maturing and enlargement of the breasts, widening of the pelvis, increased body fat, growth of pubic and underarm hair, growth spurt
Secondary male characteristics
Growth of pubic, underarm, facial and body hair, enlargement of the larynx, causing the voice to break and deepen, increased muscular and bone development, widening of the shoulders, growth spurt, increased secretion of sebum in the skin
Fibroids
Benign tumours. Result from overproduction of cells. Do not spread
Fibroids symptoms
Prolonged menstrual bleeding (lead to anaemia), pain, miscarriage, infertility
Fibroids cause
Uncertain. May be abnormal oestrogen response. Larger in women taking the pill
Fibroids prevention and treatment
Small require none, frequent examinations. Large fibroids removed by surgery. May be necessary to remove uterus (hysterectomy)
Copulation
Act of sexual intercourse
Orgasm
Physical and emotional sensations experienced at the peak of sexual excitement
Ejaculation
The release of semen from the penis
Insemination
The release of semen into the vagina, just outside the cervix
Chemotaxis
Sperm swim towards chemical released by egg
Fertilisation
Nucleus of the sperm fuses with the nucleus of the egg, forming a diploid zygote
Implantation
The embedding of the fertilised egg into the lining of the uterus
In-vitro fertilisation
Involves removing eggs from an ovary and fertilising them outside the body
Morula
A solid ball of cells formed from a zygote by mitosis
Blastocyst
A hollow ball of cells formed from the morula
Germ layers
Basic layers of cells in the blastocyst from which all adult tissues and organs will form
Gestation
Length of time spent in the uterus from fertilisation to birth (266 days, 38 weeks, 9 months)
Lactation
The secretion of milk by the mammary glands (breasts) of the female
Birth control
Methods taken to limit the number of children that are born
Contraception
The deliberate prevention of fertilisation or pregnancy
Prolactin function
Stimulates milk production
Where is prolactin produced?
Mother’s pituitary gland
Methods of contraception
Natural, mechanical, surgical and chemical method
Natural contraception
Avoid intercourse when pregnancy is likely in menstrual cycle
Mechanical contraception
Use of mechanical barriers. Condoms, diaphragms, caps
Chemical contraception
Use of spermicides or hormones. The pill.
Surgical contraception
Sterilisation for females (tubal ligation). Vasectomy for males. Permanent.
FSH (follicle-stimulating hormone)
Produced where. Produced when. Functions
Pituitary gland. Days 1 to 5. Stimulates eggs and Graafian follicle to develop (which secretes oestrogen).
Oestrogen
Produced where. Produced when. Functions
Graafian follicle (ovary). Days 5 to 14. Causes endometrium to develop. Inhibits FSH. Stimulate LH release
LH (luteinising hormone)
Where. When. Functions
Pituitary gland. Day 14. Causes ovulation. Graafian follicle to develop into corpus luteum (makes progesterone)
Progesterone
Where. When. Functions
Corpus luteum (ovary). Days 14 to 28. Maintains endometrium. Inhibits FSH and LH production (Prevents further pregnancies).
