Jones - reading

Question 1

What is fitness?

Answer 1

Survivors selected by ability to reproduce

Question 2

What is the gene pool constantly doing?

Answer 2

Adapting

Question 3

What is the purpose of reproduction?

Answer 3

Pass genes to next generation

Question 4

How do most organisms reproduce?

Answer 4

asexually

Question 5

How do unicellular organisms reproduce?

Answer 5

mitotically - produce two identical offspring

Question 6

how do complex vertebrates reproduce?

Answer 6

Partenogenesis - egg cell doesn’t need sperm to become an embryo

Question 7

How do mammals reproduce?

Answer 7

sexually

Question 8

what is produced at fertilisation?

Answer 8

zygote

Question 9

what is the function of meiosis?

Answer 9

halves genetic material

produces germ cells

Question 10

How do mammals increase genetic diversity?

Answer 10

exchanging pieces of homologous chromosomes

Question 11

What is a mechanism of recognising fitness in mammals?

Answer 11

sexual selection

Question 12

Negatives of sexual selection

Answer 12

Energy expenditure in finding, attracting and keeping a partner
exposure of both partners to death

Question 13

Why do mammals reproduce by internal fertilisation?

Answer 13

Reduced number of eggs - energy expenditure

women undergo egg loss but mainly before egg growth

Question 14

What is viviparity?

Answer 14

production of smaller eggs
development in vivo
birthing live young

Question 15

Positives of viiparity?

Answer 15

reduces pressure to develop quickly

Question 16

negatives of viviparity?

Answer 16

long gestation is demanding on females

there is a selective pressure on birthing as it can go wrong

Question 17

How long do mammals display parental care for?

Answer 17

An extended period

Question 18

What is fercundity?

Answer 18

reproductive capacity

Question 19

How does fercundity differ in males and females?

Answer 19

Males - persists throughout life, slowly declines

Females - declines steeply at 35, ends at 50, due to loss of egg quality

Question 20

Male contraception using testosterone levels

Answer 20

High testosterone leads to FSH stimulating spermatogenesis
could suppress endogenous testosterone production and therefore spermatogenesis
Shown as effective in some people - less in others
took a long time to get a low sperm count in some people

Question 21

Male contraception using small molecule inhibitors of BRDT

Answer 21

BRDT= testes specific epigenetic reader protein
JQ1 = BRDT inhibitor - targets bromodomain and prevents recognition of acetylated H4
reduces sperm number and motility without altering hormones
reversible withing 1 month

Question 22

Male contraception PLC3

Answer 22

Potential to inhibit PLC3 and prevent oocyte activation

no specific molecules found yet

Question 23

female contraception Target the zona pellucida

Answer 23

immuniation of zona pellucida

this may cause abnormal cycles

Question 24

Male contraception

Binding to the androgen and progesterone receptors

Answer 24

reduces testosterone conc in blood
effective and reversible
no serious side effects
weight gain

Question 25

Male contraception

Adjudin

Answer 25

disrupts spermatid adhesion to sertoli cells

premature spermiation - not mature enough to fertilise

Question 26

Male contraception

Retinoic acid receptor antagonists

Answer 26

Aldehyde dehydrogenase in setoli cells synthesises retanoic acid
this is required for spermatageneis

Question 27

Male contraception

Synthetic androgens

Answer 27

Supress gonadorophins and sperm production
reversible
may be incomplete suppression

Question 28

Male contraception

Nestorone and testosterone gel

Answer 28

Progestin compound
blocks testosterone production and reduces sperm production
targets sertoli germ cell adhesion or sperm motility

Question 29

Male contraception

Vasalgel

Answer 29

Reversibly blocks vas deferens
prevents passage of sperm
impairs sperm function
reversible

Question 30

Male contraception

Block to sperm delivery

Answer 30

100% efficacy after 15 days
attaches to cells in vas deferens and blocks sperm passage
leads to morpholically different sperm

Question 31

Female contraception

Combined pill

Answer 31

Supresses secretion of progestogen and estrogen
prevents ovulation as no LH surge
inhibition of follicle maturation

Question 32

Female contraception

Mini pill

Answer 32

progesterone only
estetrol - produced during pregnancy
less side effects

Question 33

Femal contraception

Vaginal rings

Answer 33

Release haormones to prevent follicle development and ovuation
does not need an trained proffessional but is longer lasting

Question 34

female contraception

emergancy contraception

Answer 34

same hormones as normal pill
delays ovulation
needs to be 1 day befor LH surge - sometimes too late
needs to be taken within 24 hours

Question 35

IUDs

Answer 35

Copper or hormonal

Question 36

Implants

Answer 36

Long lasting

hormonal

Question 37

Injections

Answer 37

hormonal

Question 38

new female contraception

Answer 38

COX2 inhibitors: less prostaglandin production and failure to ovulate
Rofecoxib: delayed follicle rupture
Meloxicam: interfers with ovulation

Question 39

Are developmental abnormalities

more likely in babies generated via ART?

Answer 39

Different types of ART: do they all have the same level
of risk?
 Cancer risk?
 Vitrification
 ICSI vs IVF?
 Imprinting disorders
 Cardiometabolic problems
 Low birth weight
 Urogenital issues

Question 40

Why are the results from different studies at odds

with one another?

Answer 40

 Underlying infertility/subfertility
 Multiple births
 Confounding variables e.g. maternal age, follow-up (closer
scrutiny following ART), genetic origin, sample size
 Differences in procedures over time and in different places
(e.g. types of medication; day of transfer; oocyte/sperm
selection criteria/culture media)
 Risk behaviours (smoking, alcohol)
 Importance of long-term follow-up

Question 41

Are developmental abnormalities
more likely in babies generated via ART?
conclusion

Answer 41

The risks do seem to be slightly higher for
some conditions.
 BUT, don’t forget that these ART procedures
result in the birth of thousands/millions of
healthy (and desperately wanted) babies.
 Additionally, the techniques are constantly
being monitored, adapted and improved.

Question 42

What methods are used to create ‘three-parent babies’? How do they work?

Answer 42

Cytoplasmic (ooplasmic transfer)
 Mitochondrial replacement therapy (MRT) via Spindle transfer (ST) or Pronuclear
transfer (PNT or PT)
 Could also consider standard Nuclear Transfer

Question 43

Are the techniques safe and effective?

Answer 43

ST appears safe in monkeys
33% effective - better than current rate
no detectable heteroplasmy
later study on humans showed abnormal separation of the second polar body

Question 44

What are the benefits?

Answer 44

Couples able to conceive via CT despite poor-quality oocytes

 Couples able to conceive via ST and PNT despite maternal mtDNA disease

Question 45

What problems can arise in offspring/future generations?

Answer 45

MtDNA heteroplasmy/persistence of donor or mutant mtDNA
 Reversion of mtDNA population due to genetic drift
 Developmental abnormalities