Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology 1 > Lecture 22- Asexual and sexual reproduction > Flashcards

Lecture 22- Asexual and sexual reproduction Flashcards

1
Q

What are the three types of asexual reproduction?

A

Budding, regeneration, reparthenogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How does budding and regeneration produce new individuals?

A

Mitosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How does budding work?

A

A bud grows by mitosis, cells differentiate before the bud breaks away

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is regeneration?

A
  • Usually replacement of damaged tissues

- Sometimes pieces of an organism can regenerate complete organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

In what organisms can regeneration be seen?

A

Echinoderms- each piece including central disk can regenerate
Colonial cnidarians such as corals- pieces broken off in a storm start new colonies
Segmented marine worms break apart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is parthenogenesis?

A

The development of offspring from unfertilized eggs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

When is parthenogenesis common?

A

Arthropods, fish, amphibians and reptiles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What can parthenogenesis determine?

A

Sex- for example, bees:

  • Male are haploid
  • Females are diploid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens in some species where the parthenogentic reproduction requires sexual behavior?

A

Females may act as males depending on cyclical hormonal states (estrogen and progesterone)
The sexual activity stimulates the release of the egg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What process produces haploid gametes through meiotic cell division?

A

Gametogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the three fundamental steps of sexual reproduction in animals?

A

Gametogenesis (making gametes)
Mating (bringing gametes together)
Fertilization (fusing gametes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the disadvantages of sexual reproduction?

A
  • Time and energy
  • Exposes to predators/damage
  • Detracts from other behaviors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does sexual reproduction require?

A

Joining of two haploid cells to form a diploid individual

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where does gametogenesis occur?

A

In the gonads- the testes and ovaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the different gametes?

A
  • Small, motile sperm

- Nonmotile ova (eggs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are gametes produced from?

A

Germ cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where do germ cells come from?

A

They are produced early in the development of the embryo and remain distinct from the rest of the cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Other than germ cells, what are other embryonic cells called?

A

Somatic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What happens to the germ cells when gonads begin to form?

A

They migrate to the gonads

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Once germ cells are within male gonads, what happens?

A

They undergo mitosis to produce spermatogonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

After germ cells have migrated into female gonads, what happens?

A

They undergo mitosis to produce oogonia

22
Q

What happens to diploid spermatogonia and oogonia?

A

They multiply by mitosis to produce primary spermatocytes and primary oocytes

23
Q

What is the next step in gametogenesis after the formation of spermatocytes and oocytes?

A

Meiosis- reduces chromosomes (haploid cells)

These cells mature into sperm and ova

24
Q

During spermatogenesis, what does the first and second meiotic division produce?

A

Two secondary spermatocytes

Four haploid spermatids

25
Q

During division of primary spermatocytes, what are the offspring connected by?

A

Cytoplasmic bridges

26
Q

What happens to spermatids?

A

They differentiate into sperm

27
Q

What is the first step in oogensis?

A

The female germ cell divides by mitosis to form oogonia and then primary oocytes

28
Q

What happens to the primary oocyte?

A

It immediately begins prophase I of meiosis

29
Q

What happens after prophase I of meiosis?

A

Development stops in many species

30
Q

What happens after development of the primary oocyte stops?

A

It grows larger and acquires nutrients

31
Q

What happens when meiosis resumes?

A

The nucleus of the oocyte divides into two daughter cells of unequal size

32
Q

What is the name of the two unequal daughter cells produced by the meiotic division of the primary oocyte?

A 
Secondary oocyte (larger cytoplasm)
First polar body (smaller one)
33
Q

What happens to the secondary oocyte?

A

It continues with meiosis to form a haploid ootid which differentiates into a mature ovum
And a second polar body which degenerates

34
Q

What is fertilisation?

A

The union of a haploid sperm and a haploid egg to create a diploid zygote

35
Q

What are the 6 steps in fertilisation?

A
  • Recognition of sperm and egg
  • Activation of sperm
  • Plasma membranes fuse
  • Additional sperm entry blocked
  • Activation of egg
  • Egg and sperm nuclei fuse
36
Q

How are interactions between sperm and eggs mediated?

A

Specific recognition molecules

37
Q

What do specific recognition molecules ensure?

A

The sperm goes towards the egg

The egg isn’t fertilised by the wrong species

38
Q

Where is it particularly important eggs aren’t fertilised by the wrong species?

A

Aquatic organisms where sperm and eggs are released to surroundings

39
Q

What adaptation do sea urchins have to make sure fertilisation occurs correctly?

A

Chemical attractants to increase sperm mobility are species specific
Protective layers

40
Q

What two protective layers must sperm pass to get to the egg in marine animals such as sea Urchins?

A

A jelly coat

Vitelline envelope

41
Q

What is an the membrane enclosed structure on the sperm head?

A

The acrosome

42
Q

What happens when egg and sperm make contact?

A

Substances in the jelly coat trigger an acrosomal reaction

43
Q

What happens during the acrosomal reaction?

A

Membranes in the sperm head and acrosome break down, enzymes are released and digest the jelly coat

44
Q

After a hole has been digested in the jelly coat, what happens?

A

Actin is polymerized, the acrosomal process extends down from the head of the sperm

45
Q

What is the acrosomal process coated with?

A

Bindin

A specific recognition molecule

46
Q

Why is the acrosomal process coated with bindin?

A

Bindin reacts with bindin receptors in the vitelline envelope

47
Q

What happens after bindin binds to bindin receptors?

A

Sperm and egg membranes fuse to form a fertilisation cone.

48
Q

Internal fertilisation involves…

A

Specieis specific mating behaviors and egg sperm recognition molecules

49
Q

What is the mammalian egg surrounded by?

A

Cumulus- cells in a gelatinous matrix

50
Q

What is beneath the cumulus?

A

The zona pellucida- a glycoprotein envelope functionally similar to the vitilline envelope

51
Q

What happens once sperm has fused and entered an egg cell?

A

Polyspermy is blocked

Mechanisms prevent entry of more than one sperm to an egg

Biology 1 (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions