Brainscape's Knowledge GenomeTM

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


See full index

Trinity Term 1 > Principles of animal development > Flashcards

Principles of animal development Flashcards

1
Q

Development is

A

self-organising

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

Describe animal fertilisation

A
  • meiosis forms haploid gametes
  • sperm provides the paternal genome
  • large variation in the amount of material supplied to the oocyte
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What can the oocyte provide?

A
  • ‘yolk’
  • organelles
  • RNAs and proteins
  • extra nutrition
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the yolk?

A

constituent molecules and energy supplies for synthesis and growth

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

Describe the early cell divisions - the basics

A
  • holoblastic cleavage
  • first three divisions perpendicular
  • radial cleavage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe radial cleavage

A
  • first division separates left and right sides of the body
  • occurs in many bilaterians
  • typical of deuterostomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Give a radially cleaving organism

A

Xenopus laevis (African clawed frog)

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

Describe protostome cleavage

A
  • spiral cleavage
  • third cell division may be twisted clockwise or anticlockwise
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

dextral spiral cleavage

A

clockwise twisting of third cell division

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

sinistral spiral cleavage

A

anti-clockwise twisting of third cell division

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

Describe the early cell divisions - the specifics

A
  • equal or unequal, depending on the taxon
  • blastomeres inherit different portions of the original oocyte cytoplasm
  • exaggerated in unequal cleavage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe equal early cell divisions

A

first 4 blastomeres of similar size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe unequal early cell divisions

A

blastomeres of very different sizes

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

Describe gastropod mollusc cleavage

A

direction of spiral cleavage determines which way the shell coils

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

Describe teloblastic cleavage

A
  • cleavage restricted to only part of the fertilised egg
  • occurs in embryos with a lot of yolk
  • as in teleost fish
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the blastula

A
  • hollow ball
  • blastocoel
  • blastoderm
  • varied across species
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe gastrulation

A
  • making layers
  • dorsal lip
  • blastopore
  • archenteron
  • yolk plug
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe the late blastula

A
  • animal pole and vegetal pole
  • marginal zone
  • blastocoel
  • yolky vegetal cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe organogenesis

A
  • ## making tissues and systems
20
Q

Describe the three germ layers

A
  • localised by gastrulation
  • go on to make the organ systems
21
Q

What does the ectoderm make?

A

nervous system and the epidermis

22
Q

What does the endoderm make?

A
  • gut and associated digestive and respiratory organs
23
Q

What does the mesoderm make?

A

muscles, skeleton, excretory system and gonad

24
Q

Describe development control

A
  • differentiation
  • pattern formation
  • morphogenesis
25
Q

Describe differentiation

A

process by which cells come to display a specific phenotype related to a specific set of functions

26
Q

Describe pattern formation

A

process of organizing cells in time and space

27
Q

Describe morphogenesis

A

movement of cells or groups of cells to form shapes and structures

28
Q

Give some examples of morphogenesis

A
  • gastrulation
  • neural crest migration
29
Q

Describe myogenesis

A
  • formation of muscle tissue from myoblast precursors
  • dividing myoblasts multiply using growth factors
  • cell multiplication ceases and cells align
  • cells fuse into myotubes that show muscle-specific proteins
  • spontaneous contraction of muscle fibre begins
30
Q

Describe the genetics of myogenesis

A
  • MyoD
  • homologous in most animals
31
Q

MyoD

A
  • encodes bHLH transcription factor
  • expression can be sufficient to convert cultured fibroblasts into myoblasts
32
Q

Describe patterning

A

spatiotemporal organisation of differentiated cells

33
Q

What are the two patterning mechanisms?

A
  • lineage-dependent mechanisms
  • organising fields of cells
34
Q

Describe patterning by asymmetric cell division

A
  • cells differentiate according to the axis of cell division
  • explains local patterns of differentiation when few cells are involved
35
Q

Describe assymetric cell division

A
  • asymmetric distribution of cytoplasmic determinants
  • cell division
  • different daughter cells
36
Q

Describe C. elegant development

A
  • adult hermaphrodite has 959 somatic cells
  • lineage of every cell is fully prescribed, always the same
  • every cell at every stage now has a name
37
Q

Describe patterning by signalling

A

cells differentiate according to their position relative to a signal, irrespective of their lineage

38
Q

Describe Wolpert’s ‘French Flag’ model of positional information relating to a morphogen gradient

A
  • position of each cell defined by morphogen concentration
  • positional value interpreted by cells at thresholds
  • pattern forms
39
Q

Describe patterning by morphogen gradient in Drosophila bicoid

A
  • maternal bicoid mRNA anchored at the anterior end of the oocyte
  • when it is translated the protein diffuses and forms a gradient
  • activates different genes at different concentrations, leading to stripes of gene expression
  • the first step to making a segmented body
40
Q

Describe patterning along embryo axes

A
  • patterning along the AP axis by bicoid
41
Q

Describe bicoid

A
  • encodes a transcription factor
  • this protein diffuses to form the gradient
  • only works because early Drosophila development is syncytial
  • zygote nucleus divides many times without cytokinesis
42
Q

Describe intercellular signalling

A
  • most animal embryos are fully cellular
43
Q

Describe the mediolateral axis

A

bilateral symmetry

44
Q

Describe development along the DV axis in zebrafish

A

Bmp signalling

45
Q

Describe development along the AP axis in zebrafish

A

Wnt

46
Q

Describe the Hox genes - the basics

A
  • intermediate transcriptional state
  • cells acquire a ‘positional identity’ relative to a signal without this immediately leading to differentiation

Trinity Term 1 (38 decks)

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