Reproduction in vertebrates

Question 1

Define reproduction

Answer 1

the process of producing a new generation of organisms from an existing generation

Question 2

How do all vertebrates reproduce?

Answer 2

sexually

Question 3

What does sexual reproduction involve?

Answer 3

The production of gametes in male and female parents

Question 4

What forms when a gamete from each parent fuses?

Answer 4

A zygote

Question 5

In order for two gametes to produce a single organism what needs to happen?

Answer 5

the gametes must be brought into contact with each other
developing embryo must be fed and protected
the young must survive young enough to reach sexual maturity

Question 6

What do different organisms use various strategies to do?

Answer 6

To bring gametes into contact
To feed developing embryo
To protect developing embryo
To ensure the young survive long enough to reach sexual maturity

Question 7

What do vertebrate groups carry out in different ways to ensure that it will be successful?

Answer 7

sexual reproduction

Question 8

What are the different stages of sexual reproduction?

Answer 8

fertilisation
development of zygote
development of young after birth/hatching
level (or absence of) parental care

Question 9

What are the possible names of an unborn baby/egg?

Answer 9

zygote
blastocyst
embryo
foetus

Question 10

Define reproductive strategies

Answer 10

the way in which each animal species ensures that each stage is completed successfully

Question 11

What are different adaptations that different reproductive strategies can come about from?

Answer 11

structural adaptations
functional adaptations
behavioural adaptations

Question 12

What can improve the chances of fertilisation (or survival of the offspring)?

Answer 12

adaptations which ensure that reproductive strategies are completed successfully.

Question 13

What happens during fertilisation?

Answer 13

the nucleus of a sperm cells enters the egg cell and fuses with the nucleus of the ovum

Question 14

Which part of the sperm cell enters the egg cell?

Answer 14

the nucleus of a sperm cell enters the egg cell

Question 15

What does motile mean?

Answer 15

able to actively move

Sperm are motile; ova are non-motile

Question 16

What two things are essential for a sperm cell to successfully fertilise an egg cell?

Answer 16

the sperm must be protected from drying out

the sperm must be guided to the ova

Question 17

Is fertilisation external or internal?

Answer 17

It can be both

Question 18

Where does external fertilisation occur most frequently?

Answer 18

In most animals that breed in water

Question 19

How do animals in water undergo external fertilisation?

Answer 19

Fish and amphibians release eggs and sperm into the water and fertilisation occurs outside the body of the female

Question 20

What are some disadvantages of external fertilisation?

Answer 20

animals are dependent on water
large amounts of sperm and eggs required
many gametes will be eaten by predators
unstable environmental factors (temp, PH, currents)

Question 21

What are some advantages of external fertilisation?

Answer 21

no need for parental care (reduces energy input from parents)
young are widely dispersed by currents (reduces competition)

Question 22

Where do offspring that undergo external fertilisation obtain food from?

Answer 22

They obtain food from the environment.

This reduces energy input from parents to offspring

Question 23

Where does internal fertilisation occur mainly?

Answer 23

in terrestrial organisms (mammals, birds, reptiles and some invertebrates)

Question 24

What is an adaptation to living on land?

Answer 24

internal fertilisation

Question 25

Where is the ovum fertilised in internal fertilisation?

Answer 25

inside the body of the female

Question 26

Do animals that lay eggs that hatch undergo internal or external fertilisation?

Answer 26

internal fertilisation (the actual process of fertilisation takes place inside the female's body)

Question 27

What are some disadvantages of internal fertilisation?

Answer 27

there must be co-operation between the male and female so that the sperm can be placed inside the body of the female

Question 28

What are some advantages of internal fertilisation?

Answer 28

not dependent on water fewer gametes are produced protection inside the body (drying out & predators) gametes meet in a contained environment (greater chance of fertilisation)

Question 29

Must organisms that have internal fertilisation be fed as they develops and grows?

Answer 29

yes

Question 30

What are three strategies of internal fertilisation?

Answer 30

ovipary - animals lay eggs ovovivipary - hatch in the body (or not long after being layed) vivipary - give birth to live young

Question 31

Do oviparous animals undergo internal or external fertilisation?

Answer 31

oviparous undergo internal and external fertilisation

Question 32

What does oviparous mean?

Answer 32

eggs are laid outside a female's body

Question 33

What are eggs protected by in frogs?

Answer 33

a gelatinous mass

Question 34

What are eggs protected by in reptiles?

Answer 34

a leathery shell

Question 35

What are eggs protected by in birds?

Answer 35

hard, brittle calcareous shell

Question 36

Are protective membranes present in eggs?

Answer 36

Yes

Question 37

In oviparous animals, does the development of the embryo occur inside or outside the female's body?

Answer 37

outside the females body

Question 38

Where does an embryo get its food from in a oviparous animal?

Answer 38

from the egg yolk

Question 39

What does ovoviviparous mean?

Answer 39

the eggs are kept inside the female's body

Question 40

How is the embryo protected in ovoviviparous animals?

Answer 40

By a soft shell inside the female's body | Protective membranes are present

Question 41

Where does the development of the embryo take place in ovoviviparous animals, inside of or outside of the female's body?

Answer 41

Inside the females body

Question 42

Where does the development of the embryo take place in viviparous animals, inside of or outside of the female's body?

Answer 42

in the uterus (obviously inside the body)

Question 43

Where does the embryo get its food from in ovoviviparous animals?

Answer 43

From the egg yolk and not from the mother

Question 44

What kind of fertilisation takes place with viviparous animals?

Answer 44

internal fertilisation

Question 45

How is the ova protected inside the females body (in a viviparous situation)?

Answer 45

protected by being inside body follicle cells membranes uterus

Question 46

How does the embryo of a viviparous animal get its food? Explain in as much detail as possible.

Answer 46

The embryo embeds in the uterine wall | gets food from mother via placenta and umbilical cord

Question 47

What temperature is required for the young of an oviparous animal?

Answer 47

environmental temperature

Question 48

Do offspring have much parental care with oviparous animals?

Answer 48

No | Birds are the only exception

Question 49

What are some examples of oviparous animals?

Answer 49

``` fish amphibians reptiles birds a few mammals ```

Question 50

What temperature are eggs/embryos kept at in the development of young ovoviviparous animals?

Answer 50

at a constant ideal temperature

Question 51

Do ovoviviparous animals require parental care?

Answer 51

Sometimes

Question 52

What are some examples of ovoviviparous animals?

Answer 52

some amphibians some reptiles some fish

Question 53

What does gestation mean?

Answer 53

pregnancy

Question 54

What temperature does the foetus of a viviparous animal need to be kept at?

Answer 54

At incubation temperature regulated by the mother

Question 55

Do the offspring of viviparous animals require parental care?

Answer 55

Yes | suckle from mother for food

Question 56

What are some examples of viviparous animals?

Answer 56

mammals only

Question 57

What is an egg that can survive and develop on land called?

Answer 57

An amniotic egg

Question 58

In what part of the amniotic egg does the embryo develop?

Answer 58

the amnion

Question 59

What kind of shell does an amniotic egg have?

Answer 59

A calcium based shell OR A leathery shell

Question 60

What is the advantage to amniotic egg?

Answer 60

They are resistant to drying out

Question 61

What enables the embryo to survive out of water, in an amniotic egg?

Answer 61

The strong outer shell

Question 62

What is an important factor to allowing reptiles to live and reproduce on land?

Answer 62

The amniotic egg

Question 63

The amniotic egg contains a number of ___ that perform functions that are vital to the development and survival of the embryo

Answer 63

membranes

Question 64

What provides the embryo with food in the amniotic egg?

Answer 64

The yolk sac

Question 65

What does the amnion do?

Answer 65

contains amniotic fluid: protects developing embryo supports developing embryo

Question 66

What is another name for the amnion?

Answer 66

The amniotic sac

Question 67

What is the allantois?

Answer 67

A bag that collects the waste products from the embryo

Question 68

Where does the chorion grow?

Answer 68

around the amnion, yolk and allantois

Question 69

What does the chorion allow?

Answer 69

gaseous exchange

Question 70

What do blood vessels connect in the amniotic egg?

Answer 70

embryo, yolk and allantois

Question 71

What do blood vessels in the amniotic egg form?

Answer 71

a structure called the umbilical

Question 72

What acts as a shock absorber in the amniotic egg?

Answer 72

The air space

Question 73

What gives the amniotic egg protection?

Answer 73

The shell

Question 74

What two things allow gaseous exchange in an amniotic egg?

Answer 74

shell and chorion

Question 75

What is albumin?

Answer 75

The main protein that occurs in the white of an egg

Question 76

What two things in an amniotic egg provide the embryo with food?

Answer 76

the yolk and albumin

Question 77

When does an egg hatch or when is a foetus born?

Answer 77

Once is has reached a specific level of development

Question 78

What are some examples of animals that can move around and feed themselves soon after hatching?

Answer 78

fish amphibians reptiles

Question 79

What are some examples of animals that vary in the level of development in the newly-born/hatched young

Answer 79

birds | mammals

Question 80

What two levels of development are there for newborn birds and mammals?

Answer 80

precocial and altricial

Question 81

What does precocial mea?

Answer 81

The pattern of growth and development of species in which the young are relatively mature and mobile from shortly after birth or hatching

Question 82

What does altricial mean?

Answer 82

The pattern of growth and development of species in which the young are born or hatched helpless. They cannot move around independently shortly after hatching or being born.

Question 83

What are are three characteristics of precocial animals immediately once they are born/hatched?

Answer 83

open their eyes hair/down present run from predators

Question 84

What are more vulnerable to predators - precocial or altricial animals?

Answer 84

altricial animals