Transcript üreme 2 - benanbiology

Reproduction in
higher organisms
Plants
Angiosperms
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Are Flowering plants
like rose, magnolia
Have covered
seeds.They protect the
seed.
Gymnosperms
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Are seed plants like
pine(conifers)
Have naked or
uncovered seeds.
Plants
Angiosperms
Gymnosperms
Reproduction in flowering plants
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Gametes are formed in reproductive organs.
Anther and ovary
The gametes which are formed by meiosis,
undergo mitosis. Meiosis
mitosis
Plant embryos are protected and fed in seeds.
Pollen transport is specialized. Wind, water,
insects.
Diploid (2n)stage is developed.
Pollination and Fertilization events are different.
Flower structure
The female part is the pistil. The pistil usually is located in the center of the
flower and is made up of of three parts: the stigma, style, and ovary. The
stigma is the sticky knob at the top of the pistil. It is attached to the long,
tubelike structure called the style. The style leads to the ovary which contains
the female egg cells called ovules.
The male parts are called stamens and usually surround the pistil. The stamen
is made up of two parts: the anther and filament. The anther produces pollen
(male reproductive cells). The filament holds the anther up.
Flower structure
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If a flower holds male and female reproductive organs it is
a full flower(perfect). Tomato, apple, cherry
If a flower has only one of the reproductive organs, it is
imperfect(unisexual) flower.
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If an individual plant is either male or female the species is
regarded as dioecious. Poplar(Kavak), salix(söğüt), fig (incir)
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However, where unisexual male and female flowers appear on
the same plant, the species is considered monoecious. Pine(Çam),
corn (mısır), walnut(ceviz), hazelnut(fındık)
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Self pollination
Fertilization
Pollination
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is the landing of
pollens on stigma.
Self pollination
 Cross pollination
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After pollination a tube grows
down the style and enters the
ovary The generative nucleus
divides into 2 by mitosis and
form 2 sperm cells.
 One of the sperm cells
unites with egg to form
zygote(2n) or embryo.
 The other sperm cell unites
with polar nuclei(2n) and
form endosperm(3n)
Double fertilization in
angiosperms.
Formation of
female gamete
Formation of
male gamete
Anther
4 Pollen sac
Ovary
Ovule (tohumtaslağı)
Polen mother cell (2n)
Megaspore mother cell (2n)
Meiosis
Meiosis
Microspore(n) (4 Cells)
4 Megaspores (n)
Mitosis vv gg vv gg
3 disappear, 1 stays alive
Pollen(çiçek tozu) (n)(4 cells)
(vegetative nucleus(tüp), generative nucleus)
1 Megaspore(n)
Mitosis
3 Mitosis
2 Sperm cells (n)(8 sperms)
Embryo sac ( 8 nucleus n)
Egg
2 synergits
2 polars
3 antipods
Formation of male gamete in
Angiosperms
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Pollen mother cells(microspore mother cell) (2n)
undergoes meiosis in pollen sac and forms 4
microspores(n).
Microspres undergo mitosis and forme pollen
with 2 nuclei. (vegetative and generative nucleus)
Vegetative nucleus forms pollen tube when it
lands on stigma during pollination.
Generative nucleus divides by mitosis and form
3 sperm cells.
Formation of female gametes
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Megaspore mother cell(2n) in the ovule undergo
meiosis and form 4 megaspores.(macrospres)
3 of the megaspores die and one lives.
1 megaspore undergo 3 mitosis and forms
embryo sac with 8 nuclei.
1 is egg cell, 2 synergid cells support egg, 3
antipod cells and 2 polar nuclei.
Double Fertilization in Angiosperms:
1 (n) of the two sperm cells fertilizes egg (n) and form the zygote(2n) than the
embryo.
The other sperm cell fertilizes polar nuclei(2n) and form a triploid (3n) structure.
Fertilization and pollination in
Angiosperms(protected seed plants)
Gymnosperms- Pine
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Seed is not covered. So seed is naked.
Usually male and female organs are on the
same plant but in different parts.
There is only one fertilization. Embryo is 2n,
endosperm is n
They pollinate by wind.
Pollination and fertilization in
gymnosperms(naked seed plant)
Seed and fruit
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Zygote
3n(triploid)cell
Ovule
Ovary
Embryo 2n
Endosperm- food supply(3n)
Seed and seed coat(testa)(2n)
Fruit (2n)
A fruit is a ripened ovary
*exocarp: outer skin
*mesocarp: fleshy to fibrous middle
*endocarp: stony or bony "pit"
*coconut, olive, peach, cherry,
apricot, almond, avocado, etc..
aggregate fruit
A fruit that develops from a single flower with several to many pistils (ie.
carpels are not fused into a single pistil)
*tissue not associated with ovary (such as the
receptacle) contributes to accessory fruit
formation
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Meyve sadece dişi organın yumurtalık dokuları
tarafından meydana getirilirse bunlara gerçek meyve
denir. Örneğin; şeftali, kayısı, üzüm.
Yumurtalıkla birlikte çiçek tablası, taç ve çenek
yapraklar beraberce gelişerek meyve oluşturuluyorsa
bunlara yalancı meyve denir. Örneğin; Çilek, elma,
armut.
Bir tane dişi organdan meydana gelen meyvelere
basit meyve denir. Örneğin; Kiraz, erik, elma.
Birkaç tane dişi organdan meydana gelen meyvelere
ise bileşik meyve denir. Örneğin; Ahududu, böğürtlen.
Ceviz, fındık, kestane gibi bitkilerin meyveleri
zamanla sertleşip kurur. Tohumları yenilen bu
meyvelere kuru meyve denir.
REPRODUCTION IN ANIMALS
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In animals gametes are formed only by meiosis.
Gametes fertilizes and form the zygote or embryo.
Fertil,ization can be inside or outside of the body.
External fertilization is seen in fishes, molluscs, frogs.
SSperm and egg unites in water and zygote develops in
water.
Internal fertilization occurs inside of the female animal.
This process enables easy fertilization . Male animal
transfers the gametes/sperms) to the genital tract of the
female. Sperms are in a liquid inwhich they can move
easily and find female gamete (egg) and fertilizes it.
Unfertilized aggs are thrown out of the body and
useless. Sharks, dolphin, whale, humans
Internal and external fertilization
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It is difficult to find and fertilize the egg in
external fertilization.
The development of the zygote and embryo
is very difficult in external fertilization.
The gamete number should be large to
maintain the fertilization.
Which of them is common in all internal
fertilization types?
I. The egg number is reduced than the external
fertilization
II. Development of the Reproductive organs
encourage fertilization.
III. The possibility of the fertilization of the egg is
very low.
a. Only I
b. Only II
d. I and II
c. Only III
e. I, II and III
Internal fertilization in birds
Egg types and properties
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Eggs are different according to their vitellus
amount. According to the egg type the
developmental type is diffrent in animals.
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The vitellus amount is more in animals with external
fertizitaion and external development than the animals
with internal fertilization and internal development.
The animals with external fertilization and external
development don’t have protective layers of amnion,
chorion and waste storing allantois.
The vitellus amount is more in animals with internal
fertilization and external development. These animals
have protective layers of amnion, chorion . Their waste
storing part allantois also gets bigger during the
development of the embryo.
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The animals with internal fertilization and internal
development don’t have so much vitellus. Because the
exchange food with placenta. Amnion and chorion is
well developed. Allantois is very small and doesn’t grow.
Because they also exchange waste material by placenta
with mother.
Reproduction in humans
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The fertilization occurs inside of the body
and embryo develops inside of the mother.
Formation of egg in humans
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Meiosis occurs in ovaries. But the meiosis in humans is
unequal division. Ony one oocyte is big and can live
and be fertilized. Oocyte develops with follicle cells
aroud it. Follicle cells protects and nourishes the egg.
Only one follicle with one egg gets mature in one
month. Every month one egg is thrown out(ovulated)
from the ovary.
The ovulated oocyte enters fallopian tube. The
fertilization happens in the fallopian tube.
After fertilization zygote forms and begins mitotic
divisions.
The fertilized egg travels down the fallopian tube and
reaches uterus where it binds and develops.
Formation of Sperms in humans
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Spermatogenesis
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Spermiogenesis
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Sperm formation occurs in seminiferous tubules
of testis.
Spern mother cells(spermatogonia) undergoes
meiosis. But these cells have cytoplasmic
bridges. These cytoplasmic bridges enables
simultaneous maturation of sperm cells.
Sperms taht are formed at the end of the
meiosis don’t have the mobility, they undergo
some changes. They lose their excess cytoplasm
and produce flagella to move. Most of the
mobility is gained in epididymis. The entire
process takes 100 days.
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Anterior pituitary
FSH- Growth of follicle,
secretion of estrogen
LH- Ovulation
Ovary secretes:
Estrogen- thickening of
uterus
Progesteron- thickening of uterus
Corpus luteum: The follicle
cells stayeing in ovary after
ovulation forms corpus
luteum. Secretes estrogen and
progesteron.
Main stages in female menstrual
cycle
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Follicle stage: Follicle with egg cell develops in the ovary
(during 5-14 days) (FSH, estrogen)
Ovulation stage: Egg is thrown out to fallopian
tube.(during 14-15 days)(LH, estrogen)
Corpus Luteum stage: the cells in the ovary produces
hormones. These hormones prepare uterus for a possible
fertilization. (15-28 days) (progesteron,estrogen)
Menstruation stage: If there is no fertilization, hormones
decrease and endometrium is thrown out from the body.
(0-5 days) (FSH)
Ovulation stage
Follicle stage
Corpus Luteum
stage
Menstruation
stage
Hormonal control of female
reproductive system
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Hypothalamus
Releasing Factor
Ant. Pit.
Follicle stimulating
hormone
FSH
 Ovary
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Development of follicle
Luteinizing hormone LH
Ovulation
Folikül
Corpus
luteum
Estrogen
Progesteron
Thickening of
endometrium
Development of
repr. organs
Preparation to
pregnancy
Feedback
LTH- Luteotropic
hormone acts on
mammary gland
Hormonal control of male
reproductive system
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Hypothalamus
Releasing factor
RF
Ant. Hypophysis
FSH
LH
Spermatogenesis
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Testis
Seminiferous
tubules
Testosteron
Hormone
production
Androgen
Spermatogenesis
Male properties
Fertilization
Fertilization
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Fertilization happens after ovulation in
fallopian tubes.
Sperm cells penetrate to the cell
membrane of the egg and acrosome
vesicle help penetration. It has hydrolytic
enzymes. Only sperm nucleus enters egg.
When it enters nuclei of gametes unite
and form 2n zygote. Embryo forms from
zygote with mitotic divisions.
Zygote undergo mitosis during its
journey to the uterus. There it binds to
the endometrium (implantation).
SPECIES
African elephant
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ADULT
MASS/kg
GESTATION
PERIOD/weeks
6000,0
88,0
Horse
400,0
48,0
Grizzly Bear
400,0
30,0
Lion
200,0
17,0
Wolf
34,0
9,0
Badger
12,0
8,0
Rabbit
2,0
4,5
Squirrel
0,5
3,5
http://www.saburchill.com/chapters/chap0038.html
Development in plants
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Dicotyledones
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Monocotyledones
Germination
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Seeds have very low water content. They have to take in
water to facilitate reactions(enzyme activity).
Seeds take in water and swell. Testa(seed coat) bursts.
Enzymes become active. Amylase breaks down starch
into glucose and use them in cellular respiration.
Proteases breakdown proteins in the endosperm.
Molecules are used in the growth of the embryo until
photosynthesis.
Wet weight
a-b : seed is inactive
e
B-c: germination begins, absorbs
water
f
C-d: seed uses food stores
abc d
time
D-e: plant starts photosynthesis and
produces new cells
E-f : plant flowers, and dies
Seed structure
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Seeds contain an embryo plant.
Radicle: will form root
Plumule: will form shoot
Cotyledones: store food.
Testa: protects embryo.
Monocotyledones(tek çenekli)
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The first leaf is single.
Seed is whole (one part)
Leaves are double
veined
Petals are 3 or multiples
of 3
Vascular bundles are not
regularly arranged.
Dicotyledones(çift çenekli)
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The first leaf is double.
Seed has 2 parts.
Leaves are net veined
Petals are 4 or 5
Vascular bundles are
regularly arranged in
circle.
Factors affecting plant development
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Environmental conditions:
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temperature
light
Soil
Water
Gases
Gravity
Nitrogen and carbohydrates
Biotic factors
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Hormones
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Encouraging
development
Auxin
 Gibberellin
 Cytokinin
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Stopping development
Abscisic acid
 Ethylene
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Development in animals
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An organism starts its journey as 1 cell(zygote)
and become an ornism with millons of different
cells. The processes which make them many and
different are as follows:
Cell division(segmentation): Zygote divides by
mitosis.
Growth: The increase in mass by feeding and
division.
Differentiation: Cells differentiate to form
different kinds of cells by gene activation.
Nature or nurture
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http://history1900s.about.com/od/auschwitz/a/mengeletwins_
2.htm
http://www.wordwiseweb.com/AUSCHWITZ/AUSCHWITZ/
twins.html
http://www.dusunenadam.com/2004/2004_06_07.html
http://www.ists.qimr.edu.au/
* http://www.washingtonpost.com/wpdyn/content/article/2005/07/04/AR2005070400845.html
http://www.sciencenews.org/articles/20050709/fob1.asp
http://www.niehs.nih.gov/research/clinical/program/groups/g
eigroup.cfm
http://www.libraryindex.com/pages/2233/GeneticsEnvironment-TWIN-STUDIES.html
Extraembryonic Membranes
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Extraembryonic membranes functions in
protection, feeding and development of the
organism.Birds, mammals, reptiles have
extraembryonic membranes.
Amnion memb:It is filled with amnion fluid.
Protects embryo and prevents drying.
Vitellus memb: It is attached to the digestive
system. It has egg yolk to feed the developing
embryo
Allantois memb: It is attached to the digestive
system(last part). It stores wastes.
Chorion: Protects embryo and other
membranes(structures). It also helps for gas
exchange with allantois.
Development of a bird embryo
General rules for embryonic
development
1.
2.
3.
Division: The number of the cells increase.
But the volume of the cells decrease. The total
volume equals to the zygote.
Gastrulation: Cell diffrentiation starts. 3
embryonic layers are formed. Endoderm,
ectoderm, mesoderm.
Organogenesis: Development of organs
Developmental stages
1. Division
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The cells formed by mitotic divisions are called
as blastomeres. When they look like berry they
are called as morula. The cells push each other
and form a space inside and this space is known
as blastocoel. This stage is called as blastula.
Each cell in blastula have the capacity to form a
new indiviual.
During division
number of the cells
increases but their
volume decreases.
2. Gastrulation
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After blastula cells begin to differentiate and
move. Embryonic layers are formed. These
layers will form the systems of the body. In
gastrula cells form a permanent space inside.
This space later will form the digestive tract of
the organism.
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During gastrulation cell layers effect each other. In that way
differentiation speeds up.
This differention with the effect of other cell layers is called
as induction(uyarılma). If the tissues from a layer is
transplanted to anoy-ther place, they can develop into a
different organ. Spemann is the scientist who investigated this
phenomena .
Embryonic Induction
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Cell differentiation and formation of the organs
are the results of the gene activation.
The interactions between cells effect the gene
activation.
The interaction between Mesoderm and
ectoderm, will cause the development of
vertebrae from mesoderm and neural tube from
ectoderm.
During the formation of eye, neural ectoderm
and head ectoderm interact.
The relative position of particular cell layers helps determine the organs
that develop.
• Inducer cells produce a protein factor that binds to the cells of the target
tissue, initiating changes in gene expression.
• Development is a process of progressive restriction of gene expression.
• At the stage called commitment, every cell's fate becomes fixed.
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1. He took out the upper ectoderm of the embryo and
put the dissected part into the tissue culture. Embryo
without upper ectoderm developed into a full embryo
without neural tube but the ectoderm didn’t developed
into neural tube.
He thought that ectoderm needs another cell layer
to differentiate into neural cord.
He cut the upper ectoderm open and took out
the mesoderm below it. Then he closed the
ectoderm again. He observed that neural cord
didn’t form from the ectoderm.
He thought that mesoderm has a role on ectoderm
for neural tube differentiation.
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Spemann used 2 embryos in this experiment. He took out
the mesoderm below the ectoderm from one of the embryos
and transplanted it to the mesoderm of the second
embryo(to a different part). First embryo didn’t form a
neural tube, but second embryo formed 2 neural tubes (one
is normal one, the other is the transplanted one)
He thought that mesoderm should effect the ectoderm of
the embryo fort he formation of the neural tube.
Eye
development
Eye is formed with the
induction of neural and
head ectoderm. Neural
ectoderm form the eye
cup(retina) and the head
ectoderm will form the lens
and cornea of the eye.
Neural
tube
formation
3. Organogenesis
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The development of
organs and tissues from
the embryonic layers is
known as organogenesis.
Gene activation,
movement of cells,
embryonic induction are
the reasons for
organogenesis. DNA is
same in each cell but
different genes are active,
so they differentiate into
different cells and organs.
Ectoderm
Mesoderm
Endoderm
Skin
ectoderm
Neural
ectoderm
muscle
digestion
skin
brain
blood
Pancreas
Nail, hair
Spinal cord
skeleton
Liver
Nerves,
sense
organs
urinary
Lung
reproductiv
e
Throid
mucosa,
bladder
http://www.visembryo.com/baby/in
dex.html
Development of a human embryo
Protection and
feeding of
embryo
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Placenta develops after the implantation of the
embryo. The blood vessels of mother and child
are very close to each other. Embryo feeds from
the maternal blood. Umblical cord has 2 arteries
and 1 vein. Placenta also functions as an
endocrine organ, secretes estrogen and
progesteron.
Birth
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http://www.me
d.upenn.edu/m
eded/public/be
rp/overview.mo
v
http://www.ms
nbc.com/modul
es/fetal_stages/
FETUS.swf
Multiple birth
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There are two common types of multiple births, fraternal
(dizygotic) and identical (monozygotic).
Identical siblings arise where one egg is fertilized and the
resulting zygote splits into more than one embryo. Identical
siblings therefore have the same genetic material.
Fraternal siblings result from the fertilisation and implantation
of more than one egg.
Yandaki şemada omurgalı bir canlı türüne ait bazı
hücreler numaralandırılmıştır. Buna göre şemada
numaralandırılmış hücrelerle ilgili olarak hangi ifade
doğru değildir?
A.
I ve II hücreler farklı genetik
yapıdadır.
B.
III ve IV hücreler mayoz ile
oluşmuştur
C.
I ve II hücrelerindeki genlerin tümü
V hücreye aktarılır
D. V. hücre mitoz geçirir
E.
V hücredeki homolog
kromozomların yarısı III, yarısı IV
den gelmiştir.
Aşağıdaki olaylardan hangisi sonucunda oluşan
hücre ana hücreden farklıdır?
a.
b.
c.
d.
e.
Kayısı bitkisinde makrospordan oluşan megaspor
hücresi
Kertenkelenin I. Oositinden oluşan II. Oosit hücresi
Papatyada generatif çekirdekten oluşan sperm
çekirdekleri
Eğrelti otunun gametofitinden oluşan yumurta
hücresi
İnsan zigotundan oluşan 2 blastomer hücresi
Aşağıda verilenlerden hangisi çevresel değişmenin
etkisi ile oluşan modifikasyona örnektir?
a.
b.
c.
d.
e.
Bazı deniz canlılarının korunmak amacı ile
deniz kumunun renginde olması
Göçmen kuşların kışı sıcak bölgelerde
geçirmesi
Paramesyumun bölünerek çoğalması sonucu
oluşan hücrelerin farklı büyüklükte olması
Kokarcanın düşmanına karşı koku salgılaması
Hayvan türlerinin uygun mevsimlerde
yavrulaması
Tüp bebek


http://www.abc.net.au/science/lcs/ivf.htm
http://biotechadventure.okstate.edu/low/teacher/basics