The document discusses reproduction and growth in humans. It describes the processes of meiosis, mitosis, gamete formation, fertilization, and the development of the zygote. It explains sexual and asexual reproduction, comparing their key differences. The document also details male and female gamete formation, the structure of sperm cells, the menstrual cycle, hormones involved and their effects, and pregnancy.
Female reproductive functions can be divided into two major phases:
preparation of the female body for conception and pregnancy and
(2) the period of pregnancy itself.
This lecture is concerned with preparation of the female body for pregnancy, and presents the physiology of pregnancy and childbirth
Female reproductive functions can be divided into two major phases:
preparation of the female body for conception and pregnancy and
(2) the period of pregnancy itself.
This lecture is concerned with preparation of the female body for pregnancy, and presents the physiology of pregnancy and childbirth
Disassembling Of the old working pc
In this Instruction, I will give a full documentation of how to disassemble a desktop PC, for parts. The specific computer that I will demonstrate with is an HP Media Center PC m7640n with a dead motherboard. Every computer is different, but this is a general guide.
If you don't fully grasp what I mean when I am describing something, please refer to the pictures!
Step 1.
Selection the required tools and equipment:
1. Screw Driver.
2. Multimeter.
3. Soldering iron.
4. Contract cleaner.
5. Brush.
Step 2.
To turn off the power:
If the PC being running, must shut down the pc before disassembling.
There are many ways to shut down your PC—you can turn the PC off completely.
Turn your PC off completely
To shut down:
For Windows 10 Select the Start button and then select Power > Shut down.
For Windows 8.1 / Windows RT 8.1
Move your mouse to the lower left-hand corner of the screen and right-click the Start button or press Windows logo key + X on your keyboard. Tap or click Shut down or sign out and choose Shut down.
For Windows 7 Click the Start button and then click the Shut down button. Click the Start button and then click the Shut down button.
Step 3: Unplugging
The first thing you do, is unplug every cable that's plugged in to your computer. That includes the following cables:
________________________________________
• Power
• USB
• Firewire
• Mouse
• Keyboard
• Internet
• Ethernet
• Modem
• AM\FM Antenna
• Cable TV
• etc...
So pretty much just unplug every cable from your computer.
Step 2: Outer Shell/Casing
Now that your computer is fully unplugged, move your PC to a clean work space, preferably a carpet. The carpet is better than tile, because screws and other small parts will roll around.
NOTICE:
If you are working on a carpet, about every five minutes touch something that is grounded (Sink faucet\pipe, wire coming from the ground part of a wall outlet). This is so you don't shock your motherboard or other parts.
First off, unscrew the four screws on the back of the computer. On most computer cases, there will be large knobs that you can unscrew by hand or by screw driver on the back-right side of the computer. The left side has small screws because on that side you can't access much on the inside.
Once the screws are removed, you can remove the side panels. On most computers, they just slide off. Start with the left side panel (the side that once had the knobs), slide it towards the back of the computer. Now you can remove the left panel. Just like the other one, slide it towards the back of the computer.
Please refer to the pictures if you are confused!
Step 3: Outer Shell/Casing (cont.)
In the last step I removed both side panels. In this step, I will be removing the front and top panels.
________________________________________
Wait For Next Part...
The topic discussed here is the Anatomy of Female Reproductive system in Human Female, Process of Oogenesis (Gametogenesis). Menstrual Cycle, hormones and its function in Oogenesis. Structure of Ovum, & Oestrous cycle in detail
REPORT ABSTRACT:
In dealing topics regarding gender and society, it is essential to discuss the anatomy and physiology of reproduction, the process of reproduction, sexual health and hygiene, adolescents, and risky behaviors. The male and female reproductive systems complement one another to produce new birth; thus, knowing about each parts of the system are fundamental in this subject. Regarding pregnancy and contraception, it is a knowledge that must be known to teens and adolescent for the future and decision-making of a teenager. Sexual healthcare and hygiene are also a primary need of every human body. It is very important to our daily routine, not just in teenage or adolescence but throughout our whole lives. Also, adolescence is when risky behaviors restrain us to become responsible adults; thus, it is important to know the different preventive interventions. Throughout this lesson, these important topics were elaborated to expound prior knowledge.
MEMBERS:
Ampig, Isidro
Arandela, Yvonne Grace
Francisco, Joseven
Labustro, Ian Harvey
Lor, Fritzie
Obejero, Maynard
Siva, Syramae
Human Reproduction System
Male reproductive system
Sperm
Female reproductive system
Hormonal Control of Human Reproduction
Male hormones
Female hormones
The Ovarian Cycle and the Menstrual Cycle
Menopause
LH and FSH are produced in the pituitary, and estradiol and progesterone are produced in the ovaries.
Dr. K. Rama Rao
Govt. Degree College
TEKKALI; Srikakulam Dt. A. P
Phone: 9010705687
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
3. Organisms reproduce to ensure the
continuation of the species and to pass
down their genes to the next generation.
There are two types of reproduction:
sexual reproduction and asexual
reproduction.
4. Sexual reproduction Asexual reproduction
New individual produced as New individual produced
a result of the fertilisation without involving the
between a male and female formation of gamete
gamete
Two individuals are involved Only one individual or parent
as parents is involved
The new individual The new individual is exactly
Inherits characteristics of like its parent
both parents
5.
6.
7. Inhuman beings, the male gamete is the
sperm while the female gamete is the
ovum.
Sperms are produced in the testes while
the ovum is produced in the ovary.
The formation of sperms is called
spermatogenesis.
Spermatogenesis occurs in the germinal
epithelium of the seminiferous tubules.
10. A spermatozoon or sperm cell consist of
head, the middle piece and the tail.
Figure 4.4 shows a spermatozoon. The
head contains enzymes to help it penetrate
the ovum. The middle piece contains a
large number of mitochondria to provide
energy for the movement of the tail.
11. The formation of ovum is called oogenesis.
Oogenesis is regulated by hormones and
occurs in the germinal epithelium of the
ovary of a female even before birth.
A cross section of the ovary is shown in
Figure 4.5.
16. The meaning of menstruation
The relationship between menstruation
and the menstrual cycle
The importance of the menstrual cycle
Hormones involved in the menstrual cycle
Premenstrual syndrome and menopause
17. Menstruation is the breakdown of the lining
of the uterus wall and its discharge through
the vagina with a small amount of blood
and some cells.
18. Menstrual cycle consisting of follicle
development, ovulation, thickening of the
endometrium and menstruation.
Thus, menstruation occurs during the
menstrual cycle
19. Firstlyprepares the inner lining of the
uterus to receive a fertilised ovum.
Secondly, it controls the development of
mature ova and ovulation, and ensures
that they occur simultaneously with the
thickening of the endometrium.
In enabling the production of the female
gamete, the ovum, the menstrual cycle
propagation of the species.
20. Two
groups of hormones involved in the
menstrual cycle
Hormones that control Hormones that control
changes in the ovaries changes in the uterus
• Gonadotrophin-releasing • Progesterone
hormone (GnRH) • Oestrogen
•Follicle-stimulating
hormone (FSH)
•Luteinising hormone (LH)
21. Hormone Site of secretion
Gonadotrophin-releasing hormone Hypothalamus
(GnRH)
Follicle-stimulating hormone (FSH) Anterior lobe of the pituitary gland
Luteinising hormone (LH) Anterior lobe of the pituitary gland
Oestrogen Follicle cells of the ovary
Progesterone Corpus luteum
22.
23. 1 day before menstruation begins, the
hypothalamus produces GnRH.
GnRH stimulates the anterior lobe of the
pituitary gland to secrete FSH and LH.
FSH stimulates the growth of a follicle in
the ovary.
The follicle produces the hormone,
oestrogen.
24. At the beginning of its development, the
follicle is small and produces a small amount
of oestrogen.
As the follicle grows, its oestrogen production
increases.
Although rising, the oestrogen level is still
relatively low.
The low oestrogen level exerts negative
feedback on the pituitary gland.
This feedback keeps FSH and LH low during
development of the follicle ( days 1-11).
25. As the time of ovulation draws near, the
maturing follicle increases its oestrogen
secretion and oestrogen levels begin to rise
steeply, and peak about day 12.
This exerts positive feedback on the
hypothalamus, resulting in increased GnRH
secretion.
High level of GnRH in turn cause FSH and LH
secterion to rise. Thus, the peak in oestrogen
level is followed by an FSH and LH peak that
occurs just prior to ovulation.
26. The high LH level has many effect:
• Stimulates the completion of meiosis I by changing the
primary oocyte in the follicle into secondary oocyte.
• It then stimulates ovulation at about the 14th day of a
28 day menstrual cycle.
• It does this by enabling enzymes to break down the
follicle so that ovulation can take place.
• After ovulation, it promotes the development of the
corpus luteum.
• LH also stimulates the corpus leteum to secrete
progesterone and oestrogen.
27. Oestrogen and progesterone are the two
female sex hormones that induce the
changes to the endometrium.
Between 1 – 5 of the menstrual cycle:
• Low level of oestrogen and progresterone
• Causes the endometrium to break down and its
blood vessels to burst.
• Menstruation occurs
28. Between days 5 – 13, higher oestrogen secretion by a
growing follicle in the ovary causes repair and growth of the
endometrium.
Increasing level of progesterone secretion by the corpus
luteum between days 15 – 21 causes the endometrium to
further vascularised and thicken to 2 – 3 mm.
The endometrium is now ready for implantation of the
embryo.
If no implantation occurs, the corpus luteum begins to
degenerate after day 21 and the resulting of low level of
progesterone causes breakdown of the endometrium and
menstruation.
If implantation occurs, the progesterone level continues to
rise and endometrium is further developed to support the
growing embryo.
29. The menstrual cycle refers to the changes in
the uterus wall of a woman that take place
every 28 days, beginning from puberty (11
years old) until menopause (45-50 years old).
The menstrual cycle is regulated by
hormones.
The hormones involved in the menstrual cycle
are Follicle stimulating hormone (FSH),
oestrogen, luteinising hormone (LH) and
progesterone.
30.
31. The menstrual cycle occurs every 28 days.
A girl starts to menstruate when she reaches
puberty.
Menstruation is the blood discharged from the
vagina when the uterine lining breaks down.
Menstruation occurs when there is no
fertilisation, and it lasts from 3 to 5 days. During
this period, FSH stimulates the development of the
follicle and the production of oestrogen to repair
the uterus lining.
From day 5 to 13, the FSH and oestrogen level
continue to increase and a Graafian follicle is
formed.
32. On day 13, the LH level increases rapidly
causing ovulation to take place on the day 14.
From day 15 to 25, the corpus luteum formed
secretes progesterone which stimulates the
endometrium of the uterus to become even
thicker and filled with blood vessels.
If the ovum is not fertilised, the uterus lining
breaks down and the corpus luteum
degenerates. This causes the progesterone level
to drop even further, followed by more
breakdown of the uterine lining, which is
discharged as menstrual flow.
33. If the ovum is fertilised, the zygote
develops into an embryo, which implants
itself into the endometrium of the uterus.
The corpus luteum continues to secrete
until the placenta is formed.
Progestrone inhibits the production of FSH
and LH causing the menstrual cycle to
stop during pregnancy.
34. Some woman suffer from PMS a few days
before menstruation, due to the imbalance
in the oestrogen and progesterone level.
During this period, they are often
depressed, irritable and tired.
Some suffer from headaches and
backaches while others gain weight easily.
35. Menopause occurs when the menstrual cycle
stops.
It occurs usually when a woman reaches 45
to 50 years of age.
During the time, very little FSH is
produced, resulting in lower levels of
oestrogen.
The follicles and the uterus walls do not
develop; there is no ovulation and the
menstrual cycle is disrupted. The
menstruation eventually stop.
36. Millions of sperms are ejaculated into the
vagina during sexual intercourse.
The sperms swim up pass the cervix into the
uterus towards the fallopian tubes.
Once a sperm penetrates the ovum, it
discards its tail, and its nucleus moves
towards the nucleus of the ovum, fertilisation
occurs.
Fertilisation is the fusion of the sperm nucleus
with the ovum nucleus to produce a zygote. It
occurs in the Fallopian tube.
37.
38. The development of the zygote begins after two
days, the zygote divides several times by mitosis
to form a solid mass of cells called the morula
followed by a blastula which is a fluid-filled sphere
with hundreds of cells around it.
One end of the blastula is made up of a mass of
cells which continue to develop into embryo, while
the remaining cells surrounding the fluid becomes
the trophoblast which later develop into the
placenta.
Once the blastula reaches the uterus, implantation
occurs.
39. Implantation is the attaching of the blastula
onto the endometrium of the uterus.
The embryo becomes the foetus after eight
weeks.
The foetus is enclosed in an amniotic sac
filled with amniotic fluid to protect it from
any physical shock.
40. There are three kinds of twins which are
identical twins, fraternal twins and
Siamese twins.
42. Formation of identical twins Formation of fraternal twins
Formed when a sperm fertilises an Formed when two ova are released at
ovum to produce a zygote. The zygote the same time, and fertilised by two
formed divides into two zygotes which different sperms
develop into two foetuses in the uterus
The foetuse are identical as they were The foetuses are not identical as they
from the same zygote are formed from different sperms and
ova
The two foetuses share the same The two foetuses do not share the
placenta but have their own umbilical same placenta. They each have their
cord own placenta and their own umbilical
cords
They are genetically identical. They are genetically not identical.
Therefore they are always the same Therefore they can be the same or
sex different sex
43. Siamese twins are formed when the mitotic
division that occurs during the formation of
identical twins is incomplete.
As a result, the twins are joined at the
parts of the body where the incomplete
division occurs.
44. During foetal development, the foetus
depends on the mother for food and
oxygen, and to get rid of its waste
products.
The placenta helps in the exchange of
substances between the foetus and the
mother.
The foetus is connected to the placenta by
the umbilical cord.
45.
46. The placenta arises from the chorion
(trophoblast at the embryo stage) which
extends fingerlike projection called villi, into
the endometrium to make contact with the
uterine blood.
The finger-like villi help to increase the
surface area for the exchange of nutrients.
The membrane of the chorionic villi separates
the foetal blood from the mother’s blood.
47. Diffusion of nutrients occur across the
membrane of the chorion.
The umbilical arteries carry deoxygenated
blood, carbon dioxide and waste products
from the foetus to the placenta while the
umbilical vein carries oxygenated
blood, nutrients, antibodies and hormones
from the mother’s artery to the placenta.
48. Newly married couples should start family
planning to prepare themselves for
parenthood. Family planning helps them
decide when to start a family and how
many children they want to have.
If they do not want to start a family yet,
they can prevent pregnancy by using the
various method of contraception available
today, made possible by the advancement
in science and technology.
49. Avoid sex during the fertile period
Insert an intrauterine device (IUD) into the uterus (by a
doctor)
Place diaphragm (domestic shaped structure that is
made of rubber) at the cervix
Use a condom
Take oral contraceptives pills (prescribed by a doctor)
Apply spermicides to the vagina to kill the sperms
Vasectomy for men where the vas deferens in a man’s
body are cut surgically.
Tubal ligation in woman, where the Fallopian tubes are
surgically cut off to pevent pregnancy.
50. Blocked Fallopian tubes
Difficulty in implantation of zygote
Inability to produce an ovum due to
hormonal imbalance
Low sperm count
51. Sperm bank
a sperm bank is a place where sperms are frozen and
stored in liquid nitrogen under -2000C.
Artificial insemination
sperms are collected and injected into the uterus of a
female during her fertile period.
In vitro fertilisation
This method is used for females with blocked Fallopian
tubes. The ovum is extracted from the ovary during
ovulation and placed in a Petri dish containing the
husband’s sperms. After fertilisation, the embryo is
implanted into the uterus where it continues its
development. The baby is called a test tube baby.
52. Surrogate mother
a surrogate mother is a woman who
gives birth to a baby for another woman
who is unable to conceive due to
abnormalities in the uterus. In vitro
fertilisation is carried out using the ovum
and sperms of the parents but the embryo
is implanted into the uterus of the
surrogate mother.
53. Sexually-transmitted diseases are
transmitted by sexual contact. They are
also known as venereal diseases.
Example of sexually transmitted diseases
are syphilis, gonorrhea and AIDS.
54.
55.
56.
57. Inflowering plants or angiosperms, both
male and female gametes are produced in
flowers.
58. The male reproductive structures in a
flower are the stamens.
Each stamen consists of two parts that is:
•The filament: a little stalk which holds the anther
•The anther: the place where the pollen grains are
produced
59. The female reproductive structures are the carpel
which consists of three parts, that is
• A stigma a sticky surface at the apex of the
style
• A style a stalk that join the stigma to the
ovary
• An ovary the structure that carries the ovule
60.
61. The anther has four pollen sacs
Each pollen sac contains hundred of cells
called pollen mother cell.
Pollen mother cell (2n)
meiosis
4 Microspores, (n)
mitosis
Tube nucleus and generative nucleus
develop
Pollen grains
* Microspores male gametophyte
62.
63. (a) Embryo sac mother cell in the ovule undergoes meiosis and forms
four haploid megaspores.
(b) Three of the four megaspores die, leaving one megaspore in the
ovule.
(c) The functional megaspores enlarges to many times its original size,
filling up most of the ovule.
(d) The nucleus of the megaspores then undergoes three mitotic
division and form eight haploid nuclei.
* Megaspores female gametophyte
64. Three of the eight nuclei migrate to one
end of the cell forming antipodal cells.
Another two move to the centre to form
polar nuclei.
The last three nuclei at the other end,
nearest the ovule opening, form an egg
cell clamped by two synergid cells.
The structure thus formed is known as the
embryo sac.
65.
66. Pollination: the process in which ripe
pollen from an anther are transferred into a
stigma.
The landing of a pollen grain on a stigma
starts the fertilisation process.
Sugar in the stigma stimulate the pollen
grain to germinate and form a tube known
as a pollen tube.
The pollen tube grows into the style
towards the ovule.
67. At the same time, the generative nucleus
divides by mitosis into two male gamete
nuclei.
Led by the nucleus tube, the male nuclei
move down the pollen tube.
When the pollen tube reaches the ovary, it
penetrate the ovule through the micropyle.
The nucleus tube disintegrates leaving a clear
passage for the male nuclei to enter the
embryo sac.
68. One of the male nuclei fuses with the egg cell to
form a diploid zygote (2n).
The other male nucleus moves further in to fuse
with the two polar nuclei forming a triploid nucleus
(3n).
The triploid nucleus then divides to form a special
nutritive tissue called the endosperm.
The zygote itself divides and grows into an
embryo.
The outer layer of the ovule loses moisture and
develops a hard seed coat.
The seed coat protects the embryo and its
endosperm.
69.
70. The process of fertilisation in the ovule
mostly happen twice in flowering plants.
The first time it happens, a diploid zygote
is formed.
The second time it happens, a triploid
nucleus is formed.
Thus, the process is known as double
fertilisation.
71. After
fertilisation, the ovary and its
constituents develops as shown below:
• Ovule seed
• Wall of ovule seed coat
• Zygote embryo
• Ovary wall fruit wall
• Ovary fruit
72. Double fertilisation helps flowering plants
to survive because each new generation
carries its own temporary food store in the
endosperm of the seed.
The endosperm provides the nutrition and
energy that is needed by the embryo for its
growth.
73. Learning outcomes:
• The parameter for measuring growth
• The sigmoid growth curve of an organism
• The growth curve of humans
• The growth curve of an insects
74. The meaning of growth:
• It can be described as the irreversible increase in
body size, mass and number of cells in an
organisms.
• The latter are quantitative changes that occurs
during growth.
• However, growth also involves qualitative changes
to cells.
75. Growth in multicellular organism can be estimated by
measuring some parameters of organism like
length, height, volume, fresh mass and dry mass over
a certain period of time
Height or length, is convenient but the problem is
inaccurate. A tree for example while not increasing in
height, may continue to grow in diameter by growing
sideways.
Volume: more accurate but is frequently not practical to
measure.
Fresh mass: the measurement is inaccurate because
involve temporary changes in water content.
Dry mass: mass of organism after all moisture has
been removed by heating.
76. When a growth parameter such as height
or mass of an organism is plotted against
time, a growth curve is obtained.
The pattern of growth is about the same
for most organisms.
The curve is S-shaped and known as a
sigmoid curve.
Link
77.
78. • When the length of insects is
plotted against the time, it
shows very unusual, intermittent
growth.
• The graph has a staircase shape.
• The horizontal part indicate zero
growth. It correspond to the time
when the insect stops growing.
• The five vertical lines of curve are
sudden growth spurts. This
correspond to the time when the
nymphs cast away their old
external skeleton and new, larger
ones. This process is called
moulting or ecdysis.
• Each young stage between moults
• is called an instar.
79. Learning outcomes:
• The meaning of growth
• The types of growth in plants
• Primary growth tissue
• Secondary growth tissue
• The importance of primary and secondary growth
• The economic importance of plants that undergo
secondary growth
80. Growth can be described as the irreversible
increase in body size, mass and number of cells in
an organism.
Quantitative changes : changes in the number of
cells.
Qualitative changes : changes in shape, function
and complexity specialized with specialisation.
The process of growth can be divided into three
stages:
• Cell division stage
• Cell enlargement stage
• Cell differentiation stage
81.
82. There are two types of growth in plants, namely
primary growth and secondary growth.
Primary growth : the growth that occurs after
germination
Secondary growth
the growth in diameter of the stem, root and
trunk of plants
the growth pattern is an annual series of
sigmoid curves
such plants show unlimited growth, that is, they
grow continuously throughout their lives, and thus,
their growth curves never flatten out.
83. Perennials plants that continue their
growth from year to year
Annuals plant that complete their whole
life cycle in a year
Biennials plants that have two-year life
cycle
84. There are some
plants that do not
show secondary
growth and live as
annuals and
biennials, for
example, the pea
plant, Pisum
sativum.
85. Primary growth begins by rapid cell division in
a group of cells at the extreme tip of the stem
and root.
This group of cells divides by mitosis and
forms the apical meristem.
Growth at apical meristem leads to the
formation of mature primary tissue of the
stem and root such as the cortex and primary
phloem and primary xilem in the vascular
bundle.
This results in an increase in length of the
stem and root.
86.
87. After primary growth complete, secondary
growth continues in woody plants like trees
and shrubs.
In non-woody plants like herbs, no
secondary growth occurs.
Secondary growth is the result of cell
divisions in the lateral meristems of both
stem and the root.
The lateral meristem are the vascular
cambium and cork cambium.
88. The vascular cambium located between
primary phloem and primary xilem in
vascular bundles
The cork cambium located immediately
below the epidermis.
89. Parenchyma cells divide actively
The vascular cambium join up to form ring
The cell of cambium ring divide
Outer cells become the secondary phloem
tissue and secondary xylem tissue
Smaller ring in the rings form medullary rays
connecting the cortex with the pith
90.
91.
92. Secondary xylem develops thick walls
with deposition lignin. It then becomes
wood.
Similarly, the cork cambium beneath the
epidermis divides actively to form the outer
cork and the inner secondary cortex.
The external cork layer forms a protective
bark at the surface of the woody stem.
93. In trees of temperate climates, the activity of
the vascular cambium is not uniform
throughout the year.
In spring the cambium is more active and
form larger and thinner-walled xylem vessels
(spring wood)
In autumn the cambium is less active and
forms narrower vessels and fibers (autumn
wood)
These two kind of wood are seen together in
transverse sections of the stems, as
concentric rings called annual growth rings.
94. Each annual ring
indicates one year’s
growth.
Hence, by counting the
total number of annual
rings, the age of the tree
can be determined.
Trees in tropical countries
like Malaysia, however,
do dot show clear annual
rings because the climate
is not distinctly seasonal.
95. Primary growth:
• Responsible for the increase in height of a plant
• It anchors the plant firmly to the soil
Secondary growth:
• Enables the plants to live longer and grow throughout
their life
• They are able to support their increasing weight
• The thickened cork and bark reduce the evaporation of
water from the surface of the stem
• Protect the plants attack by insects and parasitic fungi
• They also guard the plant body against variation in
external temperature.
96. The plant have commercial value and produce the
most valuable timber, eg: meranti, kapur, keriung
and cengal.
The timber may be used as beams for buildings,
for durable fencing and high-quality furniture.
The wood and bark of plants can be used to
produce useful resins and oils.
Hibiscus, yellow bells and bougainvillea are
valuable as ornamental plants in gardens and
parks.
Durian tree, mango tree and rambutan tree
produce a substantial quantity of fruits for local
consumption and for export.