Brainscape's Knowledge GenomeTM

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


See full index

BIOSCI 107 > Cell Cycle and Development > Flashcards

Cell Cycle and Development Flashcards

1
Q

What are the 2 main phases of the cell cycle?

A

1/ Interphase

2/ Mitotic phase

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

What are the sub-phases of Interphase?

A

1) G1 phase
2) S (synthesis of DNA) phase
3) G2 phase

G is Growth of GAP phase

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

What are the sub-phases of Mitotic phase?

A

Mitosis

Cytokenisis

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

What happens in G1? (3)

A
  1. Cell is metabolically active
  2. Cell replicates all of its cellular organelles and components EXCEPT DNA AND NUCLEUS
  3. Replication of centrosomes begun
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What happens in S? (2)

A
  1. In nucleus, DNA strands separate at H bonds which held the nucleotides together
  2. New strand of DNA is synthesized opposite the old strands
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens in G2? (3)

A
  1. Cell makes sure DNA synthesis has been completed (correctly)
  2. Prepares fro Mitotic phase (synthesis of proteins and enzymes, gathering of reactants)
  3. Replication of centrosomes complete
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why do you have replication of things (organelles) in the cell?

A

Because the cell has been divided into 2 and you only have half the number of things like organelles in each half of the cytoplasm. Cytoplasm grows in the G1 phase.

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

What are the sub - phases of mitosis (as mitosis is a phase of the MITOTIC PHASE)?

A 
Prophase 
Prometaphase
Metaphase
Anaphase
Telophase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens in Mitosis? Summary

A

It is a continuous process
1. the nuclear membrane is dismantled,
2. two copies of DNA are separated from each other
3. two nuclei are reformed each containing 1 copy of DNA
4 PHASES IN TOTAL

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

What happens in Prophase? (2)

A
  1. Chromatin condenses into chromosomes, 2 copies held at centromere
  2. Mitotic spindles start to form (extension of microtubules from centromere)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What happens in Prometaphase? (3)

A
  1. Nuceloulus disappears and nuclear envelope breaks down
  2. Spindle fibres attach to sister chrmotid at kinetochores located at centomeres
  3. Kinetochore microtubles now start moving chromosomes toward middle of cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens in metaphase?

A
  1. Microtubles of mitotic spindle align centromeres at centre of mitotic spindle (metaphase plate)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What happens in anaphase?

A

Centromeres split so one copy of each chromosome (chromatid) is sent towards each chromosome dragged by microtubules of mitotic spindle.

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

What happens in telophase?

A
  1. Chromosomes revert to chromatin
  2. nuclear envelop reform
  3. each nucleolus reappears
  4. mitotic spindle breaks down
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why does DNA have to be spread out during the S phase (prior to mitosis)?

A

Machinery needs to get there to replicate DNA and has to be spread as all machinery needs to access genome to provide RNA transcript, contentiously re orientate itself.

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

What are microtubles structures as?

A

Alpha Beta Alpha Beta sub-units stuck together to elongate the cylindrical structure.

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

Which organelles are essential for cell division?

A

Centrioles and centrosomes where spindle will be anchored, specialized proteins will attach to build microtubules

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

What are kinetochores?

A

Series of proteins attach to centromeres and microtubles look for them

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

How does cytokenisis occur

A

Actin and myosin ring causes the plasma membrane to begin pinching in

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

How can you get abnormal non identical daughter cells?

A

Anaphase chromosome are lost or 2 set at wrong pole at the end aniploidy. If you add or miss a chromosomes it will be dysfunctional.

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

In rapid dividing cells, which phase in Interphase is deleted?

A

G1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

If not replicating cells, which phase are they stuck in and what else is it called?

A

G1 and then its called G0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What determines the rate of cell division?

A

Respond to changes in conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Which cells do not divide And what how many years does it take to be a complete new person?

A

Eye cells and 7 years. `

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How is the Cell Cycle regulated?

A

With checkpoints. There are three checkpoints.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

When is the first checkpoint?

A

G1 to S checkpoint

  1. Cell is fit
  2. Enough growth
  3. Has replaced the missing organelles
  4. the cytosolic synthesized all the material needed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

When do you exit and not continue the rest of the other checkpoints from the first one?

A

If in contact to other cells around you or ran out of nutrients, you do not go through G1 to S checkpoint, you exit to G0.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

When is the second checkpoint?

And when will the cell stop growth here?

A

G2 to M

  1. DNA is synthesized is taken placed and repaired everything

If not repaired and not sufficient nutrients available

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

The last checkpoint is…

A

SAC spindle assembly checkpoint

triggered by all kinetochores being attached to microtubules lining up and metaphase plate. If not, it will stopthe cell cycle at this point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is regulating the cell cycle?

A

MPF (mitosis promoting factor) and many protein complexes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What d the MPF protein complexes do to regulate cell cycle?

A
  1. Hold cells in a particular stage

2. Stimulate their passage to the next stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

In general what does the MPF do>?

A

induces mtosis in all eukaryotes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What are the two sub units of MPF?

A
  1. CDK1 (cyclin dependent kinase)

2. Cylclin B1 major player

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the concentration of cyclin during interphase and phase?

A

Conc increase during interphase, then peaks at M phase and decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is MPF?

A

Regulatory molecule which is mitosis promoting factor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What does CDK do?

A

Cyclin dependent kinase catalyses phosphorylation of other proteins to start mitosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What rae he concentration of CDK lilke in CC?

A

Doesnt change much during CC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is so different of turning on a MPF ?

A

MPF is activated by PHOSPHORYLATION of MPF CDK

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

MPF protein kinase is a cyclin dependent kinase (CDK) ture or false?

A

TRUE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

When is MPF active?

A

When bound to cyclin subunit. thus when conc of cyclin is high, more MPF is active and target proteins are phosprylated, causes the initiaition of mitosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Cyclin conc reg MPF conc

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Which phase in interphase do enzymes dephophorylate cyclin to activate MPF for phosphorylation of many diff protein types?

A

G2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What are the 4 effects of activated MPF (unphosphorluayted cyclin subunit)

A
  1. initiate M phase
  2. Phosphorylate lamins initiate nucleaur envelope breakdown
  3. Phosphorylate icrotubule assocuated proteins
  4. Phosphorylate enzymes that degrades cyclin, thus conc of cylin declines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

How are tumors made?

A

Non effective CC checkpoints keep growing and form tumor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Why do Docs check other tumor places when they find one in liver?

A

Liver is in contact with many other systematic organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What is cancer?

A

Complex fam of dis-eases caused buy cells grow in uncontroallable fashion that invade nearby tissues and that spread to othersites in the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Cancer is derived from….

A

cells in which cell cycle checkpoint have failed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Cancer onset involves 2 aspects of DNA change/mutation:

A
  1. Genes that ordinarily promote growth proto oncogense become oncogenes
  2. genes that stop pf inhibit growth tumor supressor genes become inactive
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Which oconegnes type is good and which is bad?

A

Protooncongene is good

Ocogene is bad

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What 3 ways can cancer develop?

A
  1. Mutation within gene (oncogene growth stimulatin protein) an oncongene
  2. Multiple copies of the gene excess of stimulating growth proteins
  3. Gene moved to new DNA position and under new control excess of stimulating growth proteins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

RAS signalling describe

A

Growth factor ligand attaches to (RTK) triosine receptor kinase signals molecule until RAS g protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What is an example of a mutation which can develop into cancer?

A

Defective or missing transcription factor like p53 cannot activate transcription

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Human fertilization compared to animals is that….

A

Highly selective process

Not synchronised insemination and ovulation not many signals. Thus, sperm has developed (some stay in the lower reproductive, sperm stay behind in case there is no egg)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What is the path of the sperm cell?

A

Corona radiata
Zona pellucida
Plasma membrane of secondary oocyte
Cytoplasm of secondary oocyte

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What is the first polar body?

A

egg has already undergone first miotic division containing unwanted chromosomes.

Large cell containing all nutrients and proteins for few days of life and can tomake new transcripts on the first few days of life. Invest in one

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Which layer does the sperm penetrate?

A

Zona pellucida

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What happens when a sperm penetrates the zona pellucida?

A

The egg fuses and engulfs the sperm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What happens in fertilisation?

A

Acrosome reaction allowing sperm to penetrate zona pellucida then plasma membrane binding (oolemma) and sperm egg fusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Sperm penetration differs in humans as the…..

A

Sperm tail is not cut off when its is penetrated into the zona pellucida

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What is cortical granule release?

A

Block polyspermy, releases enzymes which harden zona pellucida to prevent more sperm from coming in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

When do eggs undergo cleavage?

A

AS the fertilised egg is being wafted down the fallopian tubes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What are stages/names of pre implantation development of the zygote?

A
  1. cleavage of zygote two cell (made up of two blastomeres polar bodies, and the zona pellucida)
  2. Cleavage of zygote 4 cell
  3. Morula
  4. Blastocyst
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Blastocyst is made out of 2 things which are:

A
  1. Trophoblast (food and precursor)

2. Inner cell mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What is the trophoblast role?

A

outer layer of the blastocyst will later be part of placenta provides nutrients to developing embryo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

ICM role?

A

Insulated from contact with intraterine evironment

Will form embryo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Blastocyst needs much energy to grow, where does the energy come from/

A

gLYCOLOSIS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What is the blastocoele?

A

Space inside the blastocyst where ICM resides to one side surrounded by the TROPHOLBLAST

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

What happens in day 7?

A

Blastocyst needs to burrow into the uterine endometrium and becomes enclosed within endometrium by day 10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Trophoblast develops into 2 different kinds of extraembroyonnic tissue:

A

Cytotrophoblast

Synctiotrophoblast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Cytotrophoblast

A

Protective membrane outside the embryo itself

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

Synctiotrophoblast

A

Multinucleate layer of cytoplasm very invasive release enzymes make hole for blastocyst to migrate into

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

Two tissue types in embryo development of day 8

A

Hypoblast primitive endoderm

Epiblast primitive ectoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

OUtgrowth of hypoblast is…

A

mesoderm like tissue beginning of yolk sac

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

What is the first stage of the maternal fetal interface?

A

formation of amniotic cavity, lacunae where mothers blood fill syncotiotophoblast absorb nutrients and give to ICM

Fluid filled amniotic cavity develops as ICM separates from trophoblast
Provides shock absorbance, prevent adhesion and drying out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

Role of yolk sac?

A
  1. provides blood cells
  2. supplies nutrients
  3. shock absorber
  4. prevent drying out
  5. gives rise to GI tract
  6. primoridal germ cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

What is the role of chorion?

A

Prtects embryo and fetus from maternal immune system. Also gives rise to the placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

What happens in week 3?

A

Gasturalation
Three primary germ cells layer established
Organ development begins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

By week 5 the embryo is where?

A

Hanging out of the endometrium, in the uterine cavity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

What is gasturaltion?

A

Formation of primitive streak

Inavigation (push cells out strat process of embryo proper)
Endoderm Mesoderm Ectoderm

Where they can feel pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

Cloacal membrane is the…

A

tail end anus rectum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

Orpharngeal membrane is the ….

A

head end form mouth connect to oral cavities.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

What is role of notochordial process?

A

drives the action release morphagens cells close to morphogens change rapidly the far you are the less change differently DEGRADATION

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

What does notochord give rise to?

A

Vertical bodies like neural plate spinal cord, give rise to vertebrae discs and rarely a tumor called chrodoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

Spina bifida women prevent by eating?

A

Bread with folate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

Which end is the primitive streak at?

A

The tail end

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

Notochord induces what cells?…

A

induction of ectodermal cells above it (as the notochord is in the mesoderm layer) to form the neural plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

Why do humans not reproduce asexually?

A

We want genetic variation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

Meiosis makes

A

half the number of chromosomes of sperms and egg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

What is meiosis

A

a type of nuclear division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

What two cell divisions make up meiosis?

A

Meiosis I and meiosis II

91
Q

What happens before meiosis?

A

Each chromosome in the diploid 2n parent cell is replicated

92
Q

What results when replication is complete?

A

Each chromosome consists of 2 identical sister chromatids attached at centromere

93
Q

What happens in meisois I

A

homolougous chromosomes of each pair separate and go to different daughter cells.

Although each daughter cell is hapoloid, each chromosome has two identical sister chromatids still attached at the centromere

94
Q

What happens in meiosis II ?

A

Sister chromatids of each chromosome separate and go to each of two daughter cells

95
Q

What happens at the end of meiosis II?

A

There are 4 haploid gametes each containing one copy of each chromosome.

96
Q

What are the 5 phases of Meiosis I?

A 
Early prophase
Late prophase
Metaphase
Anaphase
Telophase
97
Q

What happens in early prophase ?

A

Homologous chromosome pairs come together in a process called synapsis.

Structure resulting is tetrad, 2 homologs. Non sister chromatids

98
Q

What happens in prophase II?

A

chromosomes condense, nuclear membrane dissolves, mitotic spindle begins to form

99
Q

What happens in metaphase I?

A

Tetrads migrate to metaphase plate.

Spindle form and attach to centromeres on chromosomes, homologous pairs of chromosomes align along the middle of the cell (random assortment??)

100
Q

What happens in anaphase I?

A

Homologs separate and begin moving top opposite sides of cell

Spindle fibres shorten and pull homologous chromosomes apart to opposite poles of the cell (paired chromatids remain attached)

101
Q

What happens in telophase I and cytokinesis?

A

Chromosomes move to opp sides of cell then cell divides

Chromosomes decondense, nuclear membrane (may) reform, cleavage furrow forms

division into 2 haploid daughter cells. Haploid as only one copy of each chromosome

102
Q

What are the phases of Meiosis II?

A

Prophase II
Metaphase II
Anaphase II
Telophase II and cytokenisis

103
Q

What is the key difference between meiosis and mitosis?

A

Homologs pair in meiosis (in prophase of meiosis I) they migrate together to metaphse plate and separate at anaphase result in REDUCTION DIVISION but not in mitosis

Meiosis produces 4 daughter cells with half genetic material while mitosis produce 2 genetically identical daughter cells to the parent cells

104
Q

How many cell divisions in Mitosis and Meiosis?

A

Mitosis - 1

Meiosis - 2

105
Q

What is the number of chromosomes in daughter cells compared to the parent cell is mitosis and meiosis?

A

Mitosis - Same

Meiosis - Half

106
Q

Synapsis of homologs in mitosis and meiosis?

A

Mitosis - no

Meiosis - yes

107
Q

Number of crossing over events in mitosis and meiosis?

A

Mitosis - none

Meiosis - one or more per pair of homologous chromosomes

108
Q

Makeup of chromosomes in daughter cells? Mitosis vs Meiosis

A

Mitosis - identical

Meiosis - different only one of each chromosome type present, paternal and maternal segments mixed within chromosome

109
Q

Role in life cycle? Mitosis vs Meiosis?

A

Mitosis - asexual repro in eukaryotes; cell division for growth of multi cellular organisms
Meiosis - precedes production of gametes in sexually reproducing animals

110
Q

what are the three ways of genetic variation?

A
  1. Independent assortment (metphaseI)
  2. Crossing over (prophase I)
  3. Fertilisation (random union of gametes)
111
Q

What is the role of crossing over?

A

Genetic recombo produces new combo of alleles on the same chromosome

112
Q

What is the role of independent assortment?

A

Random segregation of homologous chromosomes in anaphase I generating genetic diversity.

113
Q

What happens in polycystic ovaries?

A

Eggs stop growing and get arrested in immature state. S

114
Q

What does polycystic ovaries look like in ultrasound?

A

Ring of follicles around the outside of ovary

115
Q

How does chlamydia affect fallopian tube damage or blockage?

A

Chlamydia gets into cells and replicates which damages the cell, thus no mechanism to waft through the fallopian tube

116
Q

What can blockage of fallopian tube lead to?

A

Ectopic pregnancy

117
Q

Early menopause causes? (3)

A

Turner syndrome ( exhaust eggs in their teens) genetic

Radiation therapy or chemo

Cigarette smoking

118
Q

Male infertility

A

Low numbers of sperm which don’t swim very well

Undescended testicles

Genetic defects

Infections like chlamydia

Overexposure of chemicals

119
Q

Undescended testicles?

A

Sperm damaged cos it is heated in the body

120
Q

What is a way to help with infertility for conception?

A

In vitro fertilisation

121
Q

What are the steps of in vitro fertilisation?

A
  1. Super ovulation
  2. oocyte ovulation
  3. insemination
  4. zygote culture
  5. embryo transfer
122
Q

How can people tackle the sperm issue of not being able to fertilise the egg?

A

Intra cytoplasmic sperm injection during the insemination stage (ICSI)

123
Q

What is teratogen?

A

Agent or chemical that can disturb the development of an embryo or fetus

124
Q

What can teratogens o?

A
  1. Birth defect in child

2. Halt the pregnancy outright

125
Q

What are the classes of teratogens?

A
  1. radiation
  2. maternal infections (zika virus, rubella)
  3. drugs
  4. chemicals
126
Q

How do women check prenatal?

A

Fetal ultrasound
Amniocentesis invasive
Chronic villus sampling invasive
Maternal alpha feto protein testing QUAD AFP plus

127
Q

What is the chorion made out of?

A

It is formed by extraembryonic mesoderm and the two layers of trophoblast that surround the embryo and other membranes.

128
Q

What emerges from the chorion and what does it do?

A

The chorionic villi emerge from the chorion, invade the endometrium, and allow the transfer of nutrients from the maternal blood to fetal blood.

129
Q

What is the zona pellucida made out of?

A

Glycoprotein coat

130
Q

What is cleavage? Why it happens in zygote?

A

Splitting without growth, it is rapid splitting a number of times.

131
Q

How many times do you undergo cleavage? Do you keep in the zona pellucida?

A

Until Morula stage (16 cell mass) and yes, still within zona pellucida.

2, 4, 8, 32 cells

132
Q

What happens after the formation of the morula?

A

Compaction

133
Q

What is compaction?

A

Cell are in the middle and physically get more compacted, and cells get different.

134
Q

How are the cells different from compaction process?

A

Trophoblasts and embryoblast

135
Q

What happens when the embryoblast clump even more in the middle?

A

They are now called inner cell mass (ICM)

136
Q

What is the process called AFTER cleavage?

A

Blastulation

137
Q

What happens to the zona pelucida in the first step of blastulation?

A

It starts disintegrating

138
Q

What is the first step of blastulation?

A

The embroyblast clumps to become ICM

Zona pellucida starts to disintegrate

Morula is now Blastocyst

139
Q

When do you lose zona pellucida?

A

Second step of blastulation

140
Q

What happens in the second step of blastulation?

A

Zona pellucida is GONE

Inner cell mass starts to differ:

  • There is a cavity within the ICM called AMNIOTIC CAVITY
  • Differentiate even more, the bottom of the ICM clump is HYPOBLAST and above it is EPIBLAST
141
Q

What makes up the bilaminar disk?

A

Epiblast

Hypoblast

142
Q

What does the primitive streak formation mark?

A

The next stage of embryonic development, GASTURLATION

143
Q

What is the primitive streak?

A

The site where the cells in the epiblast layer of bilaminar disc start to migrate

144
Q

Where do the epiblast migrate to?

A

They heap themselves up at the primitive streak and start burrowing their way down into the bilaminar disk into the hypoblast and everywhere

145
Q

What do the migrating epiblast cells consequent to?

A

More differentiation, not 2 layers of different cells but now a TRILAMINAR DISK of 3 germ layers

146
Q

What is the order of the new trilaminar disk germ layers? From top to bottom

A

Ectoderm
Mesoderm
Endoderm

147
Q

What is the step after gasturalation?

A

Neurolation

148
Q

In the first step of neurulation?

A

A core called notochord is formed in mesoderm layer (2nd layer) which induces change in the above layer (ectoderm) to make a neural plate

149
Q

What happens in the second step of neuraltion?

A

The neural plate cells start diving into the mesoderm layer creating a ring/tube structure called a NEURAL TUBE

Neural crest cells are also broken off

150
Q

What are neural crest cells?

A

As the cells from the neural plate move up and down into the mesoderm layer, cells break off from the ectoderm going into the mesoderm.

151
Q

What is the neural crest function?

A

Cells which had broken off called neural crest differentiate into their own special tissues

152
Q

What is happening in the first step of implantation?

A

The zona pelucida is disintegrating and the endometrium is anticipating arrival of blastocyst and creates a crypt (valleys) until the blastocyst touches the valley called APPOSITION

153
Q

Are you inside the endometrium in the first step?

A

No you are resting, can be be easily dislodged. You want to be stuck in their for nutrient transfer

154
Q

How does adhesion happen into the endometrium?

A

The trophoblast cells start multiplying and migrate/invade into the uterine endometrium

But the endometrium cells also get larger and surround the blastocyst so you embedded now

155
Q

What happens to the trophoblast when it is doing the process of adhesion?

A

It is differentiating into different sub types, syncitiotrophoblast (invasive into the crypt, and the ones that did not change is the cytoblast

156
Q

What do the syncitiotrophoblast develop?

A

As they grow into the endometrium, they develop finger like projections called villi. Cytotrophoblast also line the villi through time

157
Q

What develops in the blood vessels? What are they real close to?

A

Fetal blood vessels close to the uterine blood vessels in the endometrium but to mixed together because of the cytotrophroblast but so close nutrients can diffuse into and out (waste) fetal blood.

158
Q

Endoderm derive into?

A

GI tract and Pulmanary, lungs, liver, pancreas,

159
Q

Mesoderm derive into?

A

Muscles, Skeletal, Genitourinary - some inner layers of skin, muscles, bone, caridac musce, kidneys ,bladder, ovaries and testes

160
Q

Ectoderm derive into?

A

Skin, Nervous system - Outer layer of skin. skin related items like hair and glands, and NERVOUS SYSTEM.

161
Q

The testes function?

A

Sperm production

Testosterone (hormone) production

162
Q

What do we see inside the testes?

A

Convoluted set of tubes called semineferous tubules

163
Q

Where inside the testes are sperm made?

A

Seminiferous tubules

164
Q

Where are testosterone made in the testes?

A

Laid egg cells hang outside of the semninferous tubules

165
Q

Sperm travel from…

A

Seminiferous tubules,
(drain out to) Rate testis
(drain out to) Epididymis, (to mature),
Get out via ejaculation

166
Q

Movement of sperm from this tubes are?

A

Peristalsis

167
Q

What is the male germ cell called?

A

Spermatogonium (2n diploid cell)

168
Q

Male germ cell going through meiosis is called…

A

primary spermatocyte (2n diploid)

169
Q

What happens in meiosis I?

A

Secondary haploid spermocytes are made.

DNA replication of Primary spermatocyte
SYNAPSIS AND TETRAD FORMATION
Split into 2 secondary spermatocytes (haploid)

170
Q

What happens in meiosis II?

A

Sister chromatids separated

End up with 4 unique daughter cells, spermatids

171
Q

What are mature spermatids?

A

Sperm

172
Q

Why are spermatids not ready?

A

They need to mature, lose cytoplasm, add a tail, add a cap

173
Q

Where do spermatids mature to become sperm

A

In the epididymus

174
Q

How can these sperm be unique??

A

Crossing over and independent assortment

175
Q

Oogensis occurs?

A

In the ovaries

176
Q

The starting female germ cell is called?

A

Oogonium (diploid)

177
Q

When does oogensis occur in a female?

A

Begins in the fetal stage, in female fetus.

178
Q

When does oogenesis stop?

A

Stop in prophase I of mitosis I in fetal development

179
Q

First division in meiosis I creates?

A

A polar body `

Secondary oocyte

180
Q

What is the size of polar body in relation to secondary oocyte?

A

Smaller

181
Q

What does the secondary oocyte do now?

A

Waits to be ovulated every month. If it does, it will travel through the fallopian tube for fertilisation

182
Q

What happens if fertilisation doesn’t occur?

A

Shed in monthly period

183
Q

If fertilised?

A

Meiosis II will complete,

sister chromatids separate
one of the daughter cells which come out of the cytoplasmic division will be big and the other one will be small polar body (stuck to it but not part of the egg)

The egg will have the cytoplasm and the egg while the polar body gets nothing.

184
Q

When does fertilisation occur?

A

12-24 hours after ovulation (day 0)

185
Q

When does first cleavage happen?

A

30 hours (a day and a bit) after fertilisation

186
Q

When does the morula form?

A

3-4 days after fertilisation

187
Q

When does a blastocyst form?

A

4.5-5 days after fertilisation

188
Q

When does implantation (apposition) occur?

A

6-7 days after fertilisation

189
Q

What is happening around 8 days?

A

Trophoblast differentiates into syncytiotrophoblast and cytotrophoblast.

Embryoblast cells also differentiate into two layers; hypoblast and epiblast

Soon a small cavity forms within epiblast becoming amniotic cavity.

190
Q

What happens as the amniotic cavity enlarges?

A

Layer of squamous cells line the roof above epiblast to form amnion. The floor is the epiblast. Amnion overlies (lies on) the bilaminar disc

191
Q

What fills the amniotic sac, (amniotic fluid) ?

A

maternal blood initially then the fetus urine. This acts as a shock absorber, body temp, prevent drying out, and adhesions between skin and other surrounding tissues.

192
Q

How does amniocentesis test work?

A

Embryonic cells normally go to amniotic fluid. As they examine fetal cells and dissolved substances.

193
Q

How does the exocoelomic membrane form on the 8th day?

A

Cells at the edge of the hypoblast migrate and cover inner surface of blastocyst wall from columnar to squamous and then a form of thin membrane called exocoelomic membrane.

194
Q

What do the exocoelomic membrane and hypoblast form?

A

Wall of yolk sac. The bilaminar disc is now between yolk sac and amniontic cavity

195
Q

Fully embedded in endometrium is in what day and what else is happening?

A

Blastocyst fully embedded in endometrium. Syncytiotrophoblast expands, small spaces called lacunae develop within it.

196
Q

What is happening on the 12th day?

A

extraembryonic mesoderm forms which are derived from yolk sac and mesenchymal tissue around amnion and yolk sac.

More cavities form in the extraembryonic mesoderm and the larger one called extraembryonic coelom.

197
Q

How does the chorion protect embryo/fetus from mother immune response?

A
  1. secretes proteins that block antibody production in mum

2. promote T lymphocyte prod. suppressing immune reponse in uterus

198
Q

By the end of the 2nd week?

A

bilaminar disc connect to trophoblast by a band of extraembryonic mesoderm called connecting stalk. Connecting stalk is the future umbilical cord.

199
Q

What are 2 neural tube defects? and what is their prevalence?

A

Spina bifida
Anencephaly
1:1000 live births

200
Q

Week 3 is…

A

Gastrulation, around 15 days after fertilisation

201
Q

What is primitive node?

A

small group of epiblastic cells form round structure called primitive node.

202
Q

Which out of the three germ layers are loose?

A

Mesoderm

the other two are dense

203
Q

16 days…

A

notochoridal process

204
Q

what is allantois and when it forms?

A

When cloacal membrane forms ( during 3rd week) wall of yolk sac forms vascularised outpouching called allantois.

205
Q

allantois function

A

early formation of blood and blood vessels and associated with the development of urinary bladder

206
Q

17th day?

A

mesoderm adj to neural tube forms paraxial mesoderm.

Paraxial meso and lateral mesoderm form intermediate meso.

207
Q

End of 5th week how many somites pairs made?

A

42-44 pairs present

208
Q

by the end of 2nd week. what develops?

A

chorionic villi

209
Q

What forms placenta?

A

chorionic villi and decidua basalis of endometrium of mother

210
Q

what happening in 4th week?

A

embryo undergoes
very dramatic changes in shape and size, nearly tripling its size. It
is essentially converted from a flat, two-dimensional trilaminar embryonic
disc to a three-dimensional cylinder, a process called embryonic
folding

211
Q

What is cylinder composed of?

A

The cylinder consists of endoderm
in the center (gut), ectoderm on the outside (epidermis), and
mesoderm in between.

212
Q

Go through foldings to get a C shape

A

Folding in the median plane produces a head
fold and a tail fold; folding in the horizontal plane results in the two
lateral folds. Overall, due to the foldings, the embryo curves into a
C-shape

213
Q

what else develops as it undergoes folding?

A

Five pairs of pharyngeal arches form

somite and neural tube develop

214
Q

What do the five pairs of pharyngeal pouches consist of?

A

ectoderm
mesoderm
endoderm (contain blood, cranial nerves, cartilage. and muscular tissue)

215
Q

Incomplete or codominance

A

Heterozygous have an intermediate phenotype

Think cows, either brown (mix of black and white) or white with brown spots

216
Q

Environmental effects

A

Degree of allele expression may depend on the environment

217
Q

Epistasis

A

One gene interferes with the expression of another gene

218
Q

Multiple alleles

A

When different combo of alleles produce more than two distinct phenotypes, trait is polymorphic

219
Q

Pleiotropism

A

A gene than influence many traits rather than just one

Marfan syndrome

220
Q

autosomal dom

A

unusual (largely fetal don’t survive)

not common, too sick to reproduce except huntigtons

221
Q

autosomal recessive

A

normally 2 siblings get it but the previous generations do not (the parents are carriers like cystic fibrosis)

222
Q

Sex linked

A

Only affected are all male

The transmitters are female. Daughter are carrier because son is affected. TRACE BACK MATERNAL.

223
Q

Why the garden pea?

A

Many hybrids previously produced (expect segregation of traits)

Large number of true breeding varieties

Small and easy to grow (short generation time)

Secual organs enclosed in flower (self fertilisation and cross fertislisation)

BIOSCI 107 (8 decks)

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