Reproductive Strategies in Vertebrates

Question 1

reproductive
strategy

Answer 1

structural, functional and behavioural adaptations that improve
the chances of fertilisation and the survival of offspring

Question 2

external
fertilisation

Answer 2

fertilisation that takes place outside the female’s body, usually in
water

Question 3

internal
fertilisation

Answer 3

fertilisation that occurs inside the female’s body where the male
has deposited its sperm

Question 4

ovipary

Answer 4

eggs are laid; the embryo develops outside the mother’s body

Question 5

ovovivipary

Answer 5

young develop from eggs fertilised internally and retained within
the mother’s body after fertilisation until they hatch

Question 6

vivipary

Answer 6

the young develop inside the uterus of mother after eggs are
fertilised internally; young are nourished through the placenta

Question 7

amniotic egg

Answer 7

the embryo inside the egg is protected by a hard shell; the egg
consists of many extra-embryonic membranes that serve
different functions

Question 8

extraembryonic
membranes

Answer 8

membranes that surround the developing embryo inside the
amniotic egg or uterus.

Question 9

amnion

Answer 9

produces amniotic fluid which cushions embryo and protects it
from mechanical injury, temperature changes, dehydration

Question 10

allantois

Answer 10

collects the embryo’s nitrogenous waste and assists in the
exchange of gases

Question 11

chorion

Answer 11

allows for gaseous exchange in the amniotic egg and forms the
placenta in mammals

Question 12

yolk sac

Answer 12

contains the food reserves for the developing embryo

Question 13

precocial
development

Answer 13

when hatchlings are well developed as they hatch, able to move
and feed themselves, with eyes open – limited parental care

Question 14

altricial
development

Answer 14

when hatchlings are underdeveloped as they hatch, unable to
move or feed or fend for themselves – young require more
parental care

(AL-tricial: A Lot of parental care )

Question 15

parental care

Answer 15

includes the building of nests, protection, teaching of young and
feeding – the care, or lack thereof, directly influences the
survival of the young

Question 16

what are the 2 main types of reproductive strategies

Answer 16

1- r- strategy (little parental care)
2- k - strategy (lots parental care)

Question 17

describe r- strategy (3)

Answer 17

1- expend more energy in producing many offsprings
2- less time + energy spent on parental care
3- most offsprings die before adulthood

hint: “r” for reproducing, more energy spent spent on reproducing

Question 18

descr k- strategy (3)

Answer 18

1- expend less energy in producing many offsprings
2- more time + energy spent on parental care
3- most offsprings survive to adulthood

Question 19

name the 5 reproductive strategies

Answer 19

1- ext vs int fertilisation
2- ovipary, ovovivpary and vivipary
3- amniotic egg
4- precocial and altricial dev
5- parental care

Question 20

fertilisation

Answer 20

when a sperm cell + egg cell fuses to form a zygote

Question 21

name 4 characteristics of ext fertilisation

Answer 21

1- req water (prev desiccation)
2- gametes (sperm + egg cells) released into water
3- many gametes released
4- high mortality rates among young due to lack of protection. Ova (egg) easily dedicated and predated on

Question 22

name 2 species that are externally fertilised

Answer 22

1- fish
2- amphibia

Question 23

name 4 characteristics of internal fertilisation

Answer 23

1- dont require water
2- sperm cells released into females body
3- fewer gametes released
4- lower mortality rates among young = protection provided by the mothers body or leathery shell

Question 24

name 3 species that are internally fertilized

Answer 24

1- reptiles
2- birds
3- mammals

Question 25

name 4 characteristics of ovipary

Answer 25

ovi = egg

FeDeNT (fertilisation, dev of embryo, nutrition, type of egg)

1- fertilisation: ext (aquatic) or int (terrestrial)

2- dev of embryo (where): ext females body

3- nutrition: yolk
- little produced (aquatic) = less energy
- lots produced (terrestrial) = more energy

4- type of egg: jelly - like

Question 26

name 4 characteristics of ovovivpary

Answer 26

ovi: egg
vivi: live

FeDeNT (fertilisation, dev of embryo, nutrition, type of egg)

1- fertilisation : int

2- dev of embryo: inside females body

3- nutrition: yolk present in egg
- young independent

4- type of egg: calcareous or leathery

Question 27

name 4 characteristics of vivipary

Answer 27

vivi: live

FeDeNT (fertilisation, dev of embryo, nutrition, type of egg)

1- fertilisation: int

2- dev of embryo: inside females body

3- nutrition: young recieve nutrition from mothers body via placenta

4- type of egg: none

Question 28

name 7 things found inside and amniotic egg

Answer 28

1- amnion (membrane)
2- allantois (membrane)
3- chorion (membrane)
4- yolk sac
5- hardened calcareous/ leathery shell
6- albumen (food reserve)
7- dev embryo