Wk 12- Meiosis Fertilisation Development

Question 1

Gametes = – individual chromosomes
= h? Cell

Fertilisation = 1 paternal gamete (– cells) + 1 maternal gamete (– cells)
These form a z? = D ? Cell made of – PAIRS of chromosomes (– chromosomes)

Answer 1

23 , haploid cell
23 cells , 23 cells
Zygote = diploid cell
23 pairs , 46 chromosomes

Question 2

Meiosis:

Produces H? Cells
Undergoes 2 rounds of cell division
Meiosis 1 and meiosis 2

Meiosis 1 = 1 cell > ? genetically different cells sister chromatids/cells attached to one another
Meiosis 2 = 1 cell > ? (t?) all genetically different cells

Answer 2

Haploid cells
1>2
1>4 tetrad

Question 3

Mitosis:

1 cell > ? Identical daughter cells
Meiosis = ? Genetically different cells

Answer 3

2 identical cells

4 different cells

Question 4

Fertilisation

The fusion of s? and o? membrane
Combination of 46 chromosomes forms a ?

Sperm have 23 chromosomes only
Oocytes have 23 chromosomes + ?

Answer 4

Sperm , oocyte
Zygote

Organelles

Question 5

Zygote > m? in - days
M? > b? in - days
B? > imp? in ? Days

B? secretes enzymes that burrow/ burn into endometrium

Answer 5

Morula , 3
Morula , blastocyst 4 days
Blastocyst, implantation 5-7 days
Blastocyst

Question 6

Embryonic development takes place in week ?-?

Fetal development takes place in week ?-? birth

Answer 6

2-8

9- 38 , 9th month

Question 7

Early embryonic development

Heart cells start beating 
Early gut and limb buds 
E? / e? Start develop 
T? Forms 
Blood and b? Vessels form

Answer 7

Eye / ear
Tail
Brain

Question 8

Embryonic 5-8 weeks

Heart has - chambers 
Increase brain development 
Limbs more distinct 
D? Visible 
T? Disappears 
O? Develop

Answer 8

4 chambers
Digits
Tail
Organs

Question 9

Fetal 3 months

Heart beat detectable 
Head - whole body 
Brain increase size 
External e? Develop 
O? Begins 
G? Visible

Answer 9

Half
Ear
Ossification
Gender

Question 10

Fetal 5 months

Body size increases proportionate to h? 
E? Open 
Limbs lengthen 
Increase development of body s? 
N? Visible 
Red bone marrow produces increase b? Cells

Answer 10

Head 
Eyes 
Systems 
Nails 
Blood cells

Question 11

Maternal nutrition

Fetus receives nutrition from m? 
Fetal development can change to a? to available nutrients 
Decreased nutrition in utero = increase risk of 
C? Disease 
Hyper?
O? 
Type 2 diabetes 
R? Failure 
Reduced life span

Answer 11

Mother 
Adapt 
Cardiovascular disease 
Hypertension 
Obesity 
Renal failure