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Natural sciences

Grade 9

Life processes: healthy life

Module 7

Human reproduction

  • Reproduction is the process by which offspring are created.
  • During this process, GAMETES (generative sex cells) have to unite.
  • The male gametes are called SPERM CELLS and female gametes are OVA , or egg cells. Both gametes carry the genetic characteristics of the new individual.

Sperm cell and ovum

  • In both sexes, gametes only begin to be produced after PUBERTY . Hormones from the brain control maturation.
  • The cells are formed in the sexual organs, namely in the TESTES of the male and in the OVARIA of the female.

Male sexual organs:

    1. 2 TESTES in the external SCROTUM
  • SPERM TUBES that carry sperm cells from the testes to the PROSTATE GLAND and other glands.
  • The PENIS , which is responsible for transferring the SEMEN (sperm cells and nutrients) to the female system. The release of semen is called EJACULATION .

Female sexual organs:

    1. Two FALLOPIAN TUBES for guiding the ova from the ovaries. FERTILIZATION normally occurs here.
  • A UTERUS situated just behind the bladder and in which an infant will develop.
  • A VAGINA that receives the sperm cells from the penis and which also serves as birth canal.

Male and female sexual organs:

The menstrual cycle:

    1. A cycle that commences in girls once they have reached puberty (commencement varies between the ages of 10 and 15).
  • This cycle prepares the female body for possible pregnancy.
  • It involves the thickening of the ENDOMETRIUM inside the lower portion of the uterus in the area where an embryo will attach itself.
  • Various hormones such as progesterone and ESTROGEN are involved in preparing the body for possible pregnancy. The levels of these hormones rise and recede and cause a variety of changes that may be very uncomfortable for a girl, e.g. moodiness, tenderness of the breasts, water retention.
  • Halfway through the cycle, the egg cell (ovum) is released from the ovary. This is known as ovulation .
  • The normal duration of the cycle is 28 days. At the end of this period the endo­metrial layer loosens from the uterus and is discarded. This casting off of the endometrial tissue is known as MENSTRUATION and the process takes 3 to 7 days.
  • Girls use protective sanitary pads or tampons to absorb the flow of blood.

Fertilization: the combination of a male sperm cell with a female ovum to form a zygote

    1. This occurs in the Fallopian tube
  • A special chemical membrane develops immediately to prevent other sperm from penetrating the ovum.

Pregnancy:

    1. The zygote immediately begins to divide repeatedly to form an embryo .
  • A chemical message that travels through the woman’s body stimulates further changes.
  • The developing EMBRYO attaches itself to the ENDOMETRIUM , the lining of the wall of the UTERUS . This process is known as IMPLANTATION .
  • A PLACENTA develops where the embryo is attached and this nourishes the embryo while it is developing into a foetus. The foetus is attached to the placenta by means of the UMBILICAL CHORD .
  • The developing foetus is supplied with nutrients and oxygen through the UMBILICAL CHORD and waste materials from the foetus, like carbon dioxide, are also removed through this chord.
  • When the embryo is nine weeks old, it is called a FOETUS.
  • The development of the foetus is completed in approximately 280 days or 9 months.

Class Activity: Discussion on reproduction

1. Explain what is meant by:

a) IMPLANTATION

b) OVULATION

c) FOETUS

d) PUBERTY

e) MENSTRUATION

2. What is the function of the following?

Testis

Ovaries

Penis

Scrotum

Uterus

Fallopian tubes

Placenta

Umbilical chord

3. What is an ECTOPIC PREGNANCY?

4. Explain how the following sets of twins develop:

a) identical or monozygotic (uniovular) twins;

b) non-identical or dizygotic (fraternal) twins

c) Siamese twins

5. What determines whether the baby will be male or female? Explain.

Assessment: CLASS DISCUSSION

Were you able to complete the table and answer the questions?

[LO 1.3]

Assessment

Learning Outcomes 1 : Scientific Investigation

The learner will be able to act confidently on curiosity about natural phenomena, and to investigate relationships and solve problems in scientific, technological and environmental contexts.

We know this when the learner:

  • evaluates data and communicates findings.

Memorandum

CLASS ACTIVITY: GROUP DISCUSSION- REPRODUCTION

1. a) implantation of embryo into the wall of the uterus

b) release of ovum from ovary

c) developing embryo after two months

d) sexually mature phase in boys and girls

e) shedding of preparatory layer in the monthly cycle

2. Complete:

Umbilical cord Tube connecting foetus and placenta

3. a pregnancy in which the embryo is implanted in the wall of the Fallopian tube instead of the uterus

4. a) a single zygote that divides early in its development – identical information; always of the same sex

b) two zygotes and two different sperm cells; two different individuals

c) uncompleted identical division

5. father donating X or Y chromosome

Questions & Answers

How is everyone doing
Lotegeluaki Reply
good.
Cathleen
good
Flora
I didn't know it had this feature. Good, thanks for asking.
Cheriyan
getting better thanks ... how are you ?
Jim
Oh hey
Nikki
Hmm
Nikki
Doing well, thank you!
Amanda
could someone talk about the 4th level of maslow's hierarchy of needs pyramid. thanks
Neelkanth
@Neelkanth , The fourth level depicts self worth. It basically means pride enters one's life later on. Honestly, I don't confirm to the hierarchy much.
Zoya
An example, this a drastic example, : Making an 11 year old kid that has gone through basic conditioning beg for his/her life may be easy when you put a gun to their head.
Zoya
However, when you do so to a man in his late 30's to 40's who has also gone through the same conditioning in his childhood, it may be more difficult to make him beg. This is because he has earned a reputation. Went up the hierarchy
Zoya
when young children speak in short phrases using verbs and nouns,what it is referred to
Simran Reply
how old? generally that's how kids talk isn't it?
Ezra
especially shy ones
Ezra
slang
Emma
what are the social psychology concepts
MICOT Reply
their are about seven main theories... hope someone could help out with main one and their characteristic
Neelkanth
the self concept, social cognition, attribution theory, social influence, group processes, prejudice and discrimination, interpersonal processes, aggression, attitudes and stereotypes.
Deepa
what is different between psychoanalysis, psychopathology?
salma
when do children form oppions
Tasha Reply
they sit in home and play home toys
muhammad
oppions?
Grace
How to know other person
RAGHAV Reply
what is the nature and scope of biopsychology?
Pratibha Reply
working along with neurologists and doctors closely on the field related to brain and nerves
devesh
How can one over come a sleep debt
Andy Reply
how does an algorithm save you time and energy when solving a problem
john Reply
by directing your attention or misdirecting your attention to a particular topic
frederick
can an obsession with blood and Gore be caused by psychological trauma
Dalton Reply
psychological trauma is a bit of a wild card in the case of long term effects. everyone has their own unique experience and I dont see why the example in your question couldn't be a possible manifestation.
Elle
it would be a bigger possibility of this resulting from trauma if this began after you witnessed a violent or gory event. however this often comes from the amount of violence and gore we are exposed to through social media, the news, and fictional material like books, movies and video games.
andrina
how can the bipolar and mood disorder can prevent?
Shana Reply
Control stress. Stress is a major bipolar trigger. ... If you would control stress you will simply feel good ....if you want to know more about this DM @shana mae
KhaLid
That brings us to the next question.. How do we actually control stress in an effective way?
Looney
well for me mindfulness meditation techniques are very much effective for coping with stress ....
KhaLid
please what are the major things I need to know now in psychology,because I'm a new student of psychology.
Godwin
Godwin if it is your begining in this field you should first clear some concepts like what is psychology it's etymology , structuralism,functionalism , behaviourism and many other perspectives .....
KhaLid
first of all are you studying in psychology or working as a psychologist
muhammad
studying Sir
Godwin
Thank you Sir Khalid.
Godwin
Muhammad Akram Both ☺️
KhaLid
Far too often, you can't control stress just like that on your own . And it will affect you On subconscious level . When it comes to meditation it's something to take seriously and best to be taught by professional.
Kira
I know there are many other ways but I found this one at my own Kira Emerala!
KhaLid
Hi friends
RAJABU
it can't be extracted I'll tell u that much
Shawnte
someone who study psychology here need help ? anyone ?
khawla
Can I ask for tips when you have no motivation and can't focus with your studies?
Jhea
For Shana, I'm sorry, I can't answer your concern at the moment, because I'm still studying about the basics of psychology 😬
Daydreaming
do meditation, start learning few pages initially n understand before moving to another topic
mini
play a sport of your choice for half an hour or listen to your fav music, develop your positive outlook towards life
mini
learn to balance work play study
mini
n health
mini
I'm struggling with BPD cptsd major anxiety disorders and going to college for a psychology degree. trying to maintain motivation is difficult. what can I do?
Sarah
I already meditate take my meds use biofeedback and several other things
Sarah
As a student, it is normal to lose motivation during college life but look at the long term goal. What do you want to achieve at the end? Divide it into small achieveable goals. Once you achieve it, focus on 2nd small goal. Last thing, it's okay to ask for help when needed. We are all in a journey.
mehdi
what's your friend's circle
muhammad
khawla saadouni yes how can I help you ?
KhaLid
Sarah you need CBT it will be effective on that what you are experiencing !!
KhaLid
implicit memory are those type of memories which can be written without any unconsciousness
Aayu Reply
m interested in this research...
Arnav
me too plz I am suffering from depression so v forgetful which has ruined my life
Sins
yes plank youth
Shawnte
0rayers poracles a d majik
Shawnte
cuffed truthfullcreatibeclarity
Shawnte
sins saintly do you need any help regarding how to cope up ?
KhaLid
nebieiluvrue
Shawnte
yes
Shawnte
what do you mean by sensory memory
Aayu Reply
sensory memory simply is an automatic response, not under conscious control. It deals with the input from the senses. 
KhaLid
what is the name of a person who introduction the techniques of factors analysis in intelligence
JobJoy Reply
what is associated with the developmental
JobJoy
lifelong spiritual advice
Zach Reply
Can you define spiritual Zach?
Emely
Are teeth part of our minds?
Kamil
who introduced the technique of factor analysis in intelligence
JobJoy Reply
Spearman's (1904)
Stephen
apart from Spearmans 1904 who again
JobJoy
Howard Garner
Komal
Got questions? Join the online conversation and get instant answers!
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Source:  OpenStax, Natural sciences grade 9. OpenStax CNX. Sep 15, 2009 Download for free at http://cnx.org/content/col11069/1.1
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