Unit Two Reproduction Flashcards
Which cells are gametes produced from
Germline cells
What does the prostate gland and seminal vesticles do
Secrete fluids that maintain mobility and viability of sperm
What does the. Seminiferous tubules do
Produce, maintain and store sperm cells
What does the interstitial cells do (three T)
Produce testosterone
What does the prostate gland do
Produce seminal fluid maintain and transport sperm cells
What does seminal vesicles do
Produce seminal fluid
maintain and transport sperm cells
What do testes do
Produce sperm and testosterone
What does the ova do
Carries a set of chromosomes
What does a Graafian follicle do
Maturation and release of an egg
What does the corpus luteum do
Releases progesterone to make uterus healthy for fetus
What does the ovary do
Produces egg
Oviduct
Transports egg to uterus
Uterus
Where fetus develops
Site of implantation
What triggers the onset of puberty
When the hypothalamus in the brain produces a - releaser hormone, this hormone stimulates the pituitary glad to release FSH (in males and females)
What are two gonadotrophic hormones
Luteinising hormone (LH) in females
Interstitial cell stimulating hormone (icsh) in males
What is the role of FSH and ICSH
FSH promotes sperm production
ICSH stimulates production of testosterone
Describe the actions of testosterone
Testosterone also stimulates sperm production
in addition it activates the prostrate gland and seminal vesicles to produce their fluid secretions
How is testosterone self regulated
High testosterone levels inhibit the secretions of FSH and ICSH from the pituitary gland this results in a decrease in the production of testosterone
Describe the role of FSH (women)
Stimulates the development of the follicle around the ovum in the ovary
What is the role of LH
Triggers ovulation
What is the role of oestrogen
Stimulates proliferation of endometrium
Effects consistency of cervical mucus
What is the role of progesterone
Promotes further development and vascularisation of the endometrium
(development of blood vessels)
Preparing it for implantation if fertilisation occurs
What is the negative feedback which prevents further follicles from developing
Progesterone and oestrogen prevent FSH and LH
What effect does the lack of LH have on the corpus luteum
Stops development
How is menstruation initiated
FSH
How long does the menstrual cycle last
28 days
Describe the stages of the follicular phase
Levels of FSH is increased
High levels of oestrogen causes LH to surge causes proliferation of the endometrium
Briefly list some of the causes of infertility in males
Mobility/motility (can the sperm swim?)
Age (as the male increases in age their sperm count will lower)
Defects (abnormally large/small sperm heads,double heads)
Describe the cycle of fertility in females
Women are only fertile for a few days during each menstrual cycle
This means that women show cyclical fertility, leading to a fertile period
What happens during a fertile period
Increase in body temperature
Mucus thin and watery
What happens during a infertile period
Mucus thick
Normal body temperature
Describe fertility in males
New show continuous fertility as they continually produce sperm in their testes from puberty onwards
What are some causes of infertility in men
Mobility/motility
Age
Defects
(MAD)
What are some genetic reasons for infertility in men
Low sperm count
Xxy chromosome
What are some diseases that cause infertility in men
Mumps
Chlamydia
Gonorrhea
Testicular cancer
What are some lifestyle reasons for infertility in males
Smoking
Stress
Obesity
Drug use
Alcohol
Describe intracytoplasmic sperm injection (icsi)
ICSI can be used i f mature sperm are defective or are very low in number
The head of the sperm is drown into a needle and injected directly into the egg
Sperm and egg will then incubated and observed for a sign of fertilisation
Describe calendar based methods of contraception
Women can only conceive for a few days each cycle
Describe barrier methods
Condom or diaphragm/cervical cap
These prevent sperm entering the uterus and reaching an ovum. These cam br made more effective with the use of spermicidal cream
Can also prevent stds
Describe sterilisation in females
The oviducts are cut and tied so that eggs cannot reach sperm ad be fertilised
Describe sterilisation in males
The spremducts (specifically vas deferents) are cut and tied so that the sperm cannot be released
Describe the pill
Oral contraceptive contains a combination of synthetic oestrogen and progesterone that mimics negative feedback and prevents the release of FSH AND LH from the pituitary gland
Describe the mini-pill
This contains synthetic progesterone and causes thickening of the cervical mucus
This prevents sperm from entering the uterus and reaching out the ovum
Describe the morning after pill
This contains a stronger dose of oestrogen and progesterone which prevents ovulation or implantation
Describe the main purpose of antenatal care
Techniques to monitor the health of the mother developing the foetus and baby
What is the role of height and wheigt measurements
Often taken to calculate te BMI of the women showing under/overwieght
What is the role of blood pressure
Up to 149/190 is normal in pregnancy
Describe the role in blood tests
Used to determine blood group also to check cholesterol and glucose levels
What is the role of urine tests
Over 100 for a wide variety of reasons usually looking for hormones or chemicals
What is the role of medical history’s
Any issues which could affect pregnancy or be inherited by a baby
What is the two ultrasound imaging scans called
Dating scans and an anomaly scan
At what stage is a dating scan preformed and what can it tell us
8 weeks and 14 weeks
Determines stage of pregnancy and the due date
At what stage is an anomaly scan preformed and what it can tell us
Between 18 and 20 weeks
Detect serious physical abnormalities in the foetus
What chemical markers are used to detect problems with either the foetus or the mother
Routine blood and urine tests are carried out throughout pregnancy to monitor the concentration of marker chemicals
Measuring a marker chemical of the wrong time could lead to a false positive result
An atypical chemical concentration can lead to diagnostic testing to determine if the fetid had a medical condition
Why is it important that the recorded levels be matched to the age of the foetus if tests are taken
Lead to a false positive
What is the difference between screening and diagnostic tests
Routine screening for those of a high risk category further tests may be carried out
Can confirm the presence of specific conditions
What is a karyotype
A picture of all the chromosome found in a cell
Describe the process of aminocentesis
Carried out later in pregnancy (15-18 weeks)
Small sample of amniotic fluid removed by a needle(small risk of a miscarriage)
DNA extracted from the sample (cultured to make more copies) then biochemically tested and karyotyped
What advantage and disadvantage does chorionic villus sampling over amniocentesis
It is more dangerous than amniocentesis it can be preformed quicker as the cells are actually dividing
What is one of the many functions of progesterone during pregnancy
Suppress the mothers immune response to the fetus
Why would a mothers immune system react to cells from the fetus if they were to enter the mothers blood circulation
The WBC will find them and respond rapidly as the immune system views these cells as forgine and dangerous
What is the Guthrie test screening for
Is a diagnostic tool to test infants for phenylketonuria (pku) a few days after birth
What what is an inborn error of metabolism
Inherited or spontaneous, leads to issues in the substitution mutation
What is phenylketonuria
Post natal tests aimed at detecting disorders inability to breakdown phenylalanine
How is phenylketonuria treated
People w/ high levels of phenylanine are put on a restricted diet that lacks the amino acids phenylalanine
What is incomplete dominance
The dominant and allele may not fully express itself
What is codominance
A Hetrozygous organum will actually express both alleles
It doesn’t have a blend of traits but shows both
When a condition has more than two alleles it is called multiple alleled. Described the inheritance of the ABO blood groups
There are more possible genotypes and phenotypes for this characteristic.
What is a pedigree analysis
Illustrating inheritance patterns and is a good way to follow the inheritance of genetic disorders through generations.
Describe an autosomal recessive trait
Autosomal recessive gene disorder can skip generations as people can be carriers
Describe an ausomal dominant trait
, you only need one copy of the dominant allele
Homo+ Hetro will be affected
Describe the incomplete dominant trait
Both incomplete dominance alleles are shown with uppercase letters in genetic diagram, but diff letters used
Describe the features of inheritance for a recessive trait controlled by a gene on the X chromosome
Alleles present on the X chromosome but not on the y are referred to as sex linked alleles
Describe some facts about recessive disorders
Males are affected more than females
Fathers cannot pass the condition to their sons because it is not present in the Y chromosome
Carrier females do not show the trait but can pass it onto sons
Some facts about dominant disorders
All daughters of affected males
All Hetrozygous individual traits
Will be affected
With a sex linked recessive condition why are men more likely to get the condition
Because the only need one coy of the recessive gene to be affected
I’m next what circumstances would he offered preimplantation genetic diagnosis (PGD)
Family history of genetic disorders or a previous child has been born with one, they may opt for IVF
What condition can be detected by pre-implantation genetic diagnosis
Chromosomal abnormalities
Cystic fibrosis
Sickle cell disease
Huntingtons disease
Duchenne muscular dystrophy
What is the part of menstruation up to the ovulation called
Follicular phase
What is the part of menstrual cycle after ovulation called?
The luteal phase
Describe artificial insemination
This involves collecting and inserting semen into the female reproductive tract without intercourse taking place
Describe stimulating ovulation
Stimulated by drugs to prevent the negative feedback effect of oestrogen on fsh secretion
It mimics the action of fsh and lh cause super ovulation and result on multiple births
What does FSH and LH control
The production of gametes throughout the reproductive life
What is an iud
Flexible plastic fitted into the uterus to prevent an embryo implanting
Could release a low dose of progesterone so it will work like a contraceptive
What is chronic villus sampling (cvs)
Carried out earlier in pregnancy 11-14 weeks
A sample of placental tissue is taken. This contains some genetical materials. High risk of miscarriage. Small sample of cells are taken from placental using ultrasound guided needle. Then It is biochemically tested and karyotyped quicker as cells are dividing
Describe Pgd
Remove 2 cells from 8 call stage of embryo. Chromosomes are examined and DNA analysed
Transfer to uterus is delayed until 5th day after fertilisation allowing time for the analysis to be completed before choice of embryos is made
