Sexual reproduction
🇬🇧
In English
In English
Practice Known Questions
Stay up to date with your due questions
Complete 5 questions to enable practice
Exams
Exam: Test your skills
Test your skills in exam mode
Learn New Questions
Manual Mode [BETA]
The course owner has not enabled manual mode
Specific modes
Learn with flashcards
Complete the sentence
Listening & SpellingSpelling: Type what you hear
multiple choiceMultiple choice mode
SpeakingAnswer with voice
Speaking & ListeningPractice pronunciation
TypingTyping only mode
Sexual reproduction - Leaderboard
Sexual reproduction - Details
Levels:
Questions:
95 questions
| 🇬🇧 | 🇬🇧 |
| Fertilized egg | Zygote |
| By what means, do substances pass between mother and fetus? | Diffusion and active transport |
| How does a placenta form? | Partly from an embryo's tissue and partly from uterus |
| Stages of implantation | 1. Ovulation- A mature follicle bursts and releases an egg into the oviduct 2. Fertilization- A sperm haploid nucleus fuses with an egg haploid nucleus forming a diploid zygote. 3.Zygote divides 4. A ball of cells is formed. 5. The cells in the ball keep dividing as it moves down the oviduct. It is now called an embryo. 6. Implantation- The embryo sinks into the soft lining of the uterus and placenta forms |
| How does embryo obtain food? | From yolk of an egg |
| How does a zygote divide? | By means of mitosis |
| Implantation | After about six days, embryo implants itself in the uterus wall. As the embryo grows, a placenta develops. |
| Piece of info | If fertilization occurs then corpus luteum does not disintegrate- it continues to divide producing progesterone to maintain and thicken uterus wall. |
| Piece of info | Blood from the baby flows continuously to and from placenta through umbilical cord. In the placenta, baby's blood comes very close to mother's blood so substances pass between mother and baby by diffusion and active transport. |
| Describe what happens when identical twins are formed. | A single zygote splits into two separate embryos. Both embryos have identical DNA. |
| Describe what happens when twins are formed(non-identical). | Two eggs released from the ovary at the same time. Each egg is fertilized by a different sperm. |
| Where does fertilization take place? | Fallopian tubes |
| Fertilization process | Haploid nucleus from a sperm fuses with haploid nucleus of an egg cell. Only one sperm fertilizes the egg. As the head of the sperm enters the egg, it triggers off the formation of an extra cell membrane around the egg. This stops any sperm entering the egg. The sperm's tail is left outside the egg. The head contains a nucleus and this fuses with the egg's nucleus. Both are haploid(23 chromosomes). After fertilization, a diploid zygote is formed(46 chromosomes). |
| Copulation | Sexual intercourse |
| What is fructose used for? | The sperm use fructose in the semen to provide energy. |
| What does the fluid from prostate glands do? | Enables sperm to be active |
| What does the fluid from seminal vesicles do | Provide food/nutrients for sperm |
| Describe process of sexual intercourse | Man's penis becomes hard and erect to penetrate woman's vagina. Ejaculation(release of sperm) occurs due to contractions of the sperm ducts and other muscles. As the sperm pass along the sperm duct and urethra, they are mixed with a fluid from seminal vesicles and prostate gland to make a sticky fluid called semen. Semen is ejaculated from penis into vagina. |
| Release of sperm | Ejaculation |
| Describe ovulation process | First, a follicle develops inside an ovary. The development of follicle is stimulated by FSH. The developing follicle secretes oestrogen. Levels of oestrogen steadily increase in blood. The oestrogen makes the uterus lining thick and spongy. LH and FSH are secreted by the pituitary gland throughout this whole time. These two hormones stimulate follicle to keep secreting oestrogen. When the follicle is fully developed, there is a surge in the production of LH. This causes ovulation to take place. The now empty follicle stops secreting oestrogen. It becomes corpus luteum. The corpus luteum secretes progesterone. Levels of LH and FSH fall. Progesterone keeps the uterus lining thick, spongy and well supplied with blood in case the egg is fertilized. If not, corpus luteum disappears gradually and progesterone is no longer secreted so uterus lining breaks down and mensuration occurs. A new follicle develops and the cycle begins again. |
| How can AID be controlled as there's no cure? | 1. Educating the public and the precautions to be taken 2. Never sharing or exchanging needles 3. Staying with an STD- free partner 4. Using a condom or any other barrier of contraception which prevents direct contact between body fluids of the two partners 5. Treating all blood and blood products used in transfusion to destroy AIDS virus |
| Diaphragm advantages or disadvantages | Adv: effective if fitted correctly. Dis: Fitting must be done by doctor but after that a woman can put it in and out when needed. |
| Diaphragm or cap | Circular sheet of rubber placed over the cervix at the top of the vagina. Spermicidal(sperm-killing) cream is first applied around the edges. Sperm deposited in the vagina cannot pass through into uterus. |
| Condom (mechanical or chemical)? | Mechanical |
| Condom advantages and disadvantages | Adv: safe method of contraception and prevents infection transmission such as gonorrhea and HIV from one partner to another |
| Condom | Placed over an erect penis and traps semen as it is released, stopping it from entering vagina |
| Advantages of breast feeding | 1. Baby receives antibodies from mother and not by baby formula 2. No formula milk can exactly replicate human milk so the baby does not get the best mix of nutrients 3. Formula milk is often based on cow's milk to which some babies may be allergic to 4. Breast fed babies do not become over weight 5. Helps form a mother-baby bond 6. Breastmilk is FREE and does not need to be strerilised. |
| Postnatal care | For first few days, breasts secrete a yellow watery fluid called colostrum on which baby feeds. Colostrum is rich in protein and contains antibodies to protect baby from diseases. After about three days, the milk is produced. At first, the baby feeds 10 to 12 times a day. The more the baby feeds , the more milk is produced. |
| Afterbirth | Contractions of the uterus continue to push the placenta until it has been expelled through vagina. Labor is then complete! |
| Delivery | Contractions of the uterus push the baby through cervix. Baby is born head first. Once the baby is out, mucus is cleared from its nose and mouth and once the baby is breathing, the umbilical cord is tied in two places and cut. |
| Dilation | When birth starts, uterus begins to contract rhythmically. This is the beginning of labor. Contractions become stronger and more frequent. The opening of cervix gradually widens(dilates) sufficient to allow baby's head to pass through. The amniotic sac bursts and amniotic fluid is released breaking of the waters. Labor takes 4-12 hours on average. |
| Gestation period | From fertilization to birth. Piece of info: few weeks before birth, the fetus comes to lie with head downwards just above cervix. |
| What are the secretion of female sex hormones controlled by? | Two other hormones secreted by the pituitary gland in the brain called LH and FSH. |
| How is HIV transmitted? | 1. Host to host through intravenous drugs users sharing unsterilized needles. 2.Semen from one partner to the blood of another, if there is any tearing of tissues during sexual intercourse 3. From an infected mother's blood to her baby blood during birth process 4. In untreated blood during blood transfusion |
| Treatment of gonorrhoea | Antibiotics |
| Gonorrhoea | Cause by bacterium. Symptoms: severe pain on urination(especially in males) since the bacterium invades the tissue of the urethra. Discharge of pus from urethra in the end of the penis in males. This infection may spread to produce inflammation of the uterus in females and epididymis in males. The disease is not fatal but can lead to sterility. |
| Sexually transmissible diseases | Disease spread through sexual contact |
| What is the dangerous virus pregnant woman are under risk of? | Rubella producing rash and fever. If rubella crosses placenta, it can cause serious harm to fetus and born deaf with disabilities. In many countries, teenage girls are offered vaccinations. |
| Embryo also called as-------- | Foetus once recognized as human being |
| Amniotic sac(amnion) | Inside uterus, embryo becomes enclosed with a sac called amnion which is filled with or secretes amniotic fluid which protects embryo from damage and maintains a suitable temperature and shock absorber. |
| What does the placenta produce? | Oestrogen and progesterone(corpus luteum produces) to stimulate growth of uterus and mammary glands |
| What substances pass from mother to baby? | Food and oxygen antibodies other substances which may be in mother's blood like alcohol, chemicals from cigarettes, viruses... |
| What substances pass from baby to mother? | Carbon dioxide, urea and other wastes |
| Uterus | Implantation and development of foetus |
| Males puberty? | Testes start secreting testosterone |
| Puberty | Stage where sex organs mature |
| Female | Female reproductive system |
| Female | Female reproductive system |
| Male | Male reproductive system |
| Male | Male reproductive system |
| How does the uterus being muscular help? | Expands a lot during pregnancy |
| Funnel of oviduct | Catches egg/ovum |
| Oviducts/fallopian tube | Egg passes along here on its way to the uterus. Fertilization occurs here. |
| Vagina | Reception of penis/semen during sexual intercourse. For passage of baby during birth. |
| Cervix | Opening at base of uterus for passage of sperm.Baby emerges through uterus at birth |
| Female puberty? | Ovaries produce oestrogen |
| Ovaries | Produce eggs(ova) |
| Why do we need to produce so many sperm? | A lot are abnormal and cannot fertilize an egg , increase chances of sperm reaching an egg. Most die before they reach the oviduct. |
| Scrotum | Protection of testis |
| Urethra | Carries urine out of the body and semen out of the body( during sexual intercourse). Also valves stop both going down at the same time.. |
| Prostate gland | Make liquid semen- nutrition for sperm |
| Seminal vesicles | Make liquid semen- nutrition for sperm |
| Passage of sperm from testes to urethra by peristalsis | Sperm duct/vas defenses |
| Epididymis | Storage and activation(make them swim)of sperm |
| What happens after mensuration? | Uterus lining repairs due to oestrogen made by ovaries and egg starts to mature inside a follicle in the ovary. |
| How many male sex hormones are there? | One- testosterone |
| How many female sex hormones are there? | Two- oestrogen and progesterone |
| Adolescence | Time when a person approaches sexual maturity |
| When is the woman most likely to conceive? | After ovulation. Fertile period is time in the menstrual cycle a woman can become pregnant. |
| What happens if egg is fertilized/pregnancy occurs? | Progesterone continues to increase and the uterus thickens to receive embryo. Progesterone prevents mensuration, therefore, period stops during pregnancy and release of more eggs. |
| What happens if egg is not fertilized? | Level of progesterone decreases by day 28 and next period starts. Day 1 of a new menstrual cycle. |
| Progesterone | Hormone which continues maintaining the uterus wall(also slightly raises body temperature). |
| What does corpus luteum secrete? | Progesterone |
| Corpus luteum | Once the follicle releases the egg, it collapses, becomes hard and yellow and is now corpus luteum. |
| Describe ovulation | Fluid pressure inside follicle causes it to burst and a mature egg is released. The release of an egg is called ovulation. The funnel of the oviduct pulls in the egg and the egg moves along the oviduct with the help of cilia by peristalsis. |
| Ovulation | Release of an egg |
| Testis function | Make sperm and testosterone |
| When does bleeding occur in a menstrual cycle? | When no egg has been fertilized and the inner lining of the uterus breaks down. |
| Sperm description? | Tail for swimming, middle piece containing mitochondria to release energy for swimming from respiration, acrosome- vesicle containing enzymes to dissolve a way through jelly surrounding egg cell. |
| What does the nucleus contain? | Chromosomes |
| Egg description? | Egg larger than sperm, egg contains large food store for development of a ball of cells following fertilization, before implantation. |
| Male and female gametes? | Egg/ovum and sperm |
| Male and female gonad? | Testes and ovaries |
| How are gametes formed? | By gonads |
| Female secondary sexual characteristics? | Menstrual cycle begins, public and armpit hair, hips widen and more fat stored in this area, mammary glands(breasts) develop, growth of uterus, ovaries start to release eggs(ovulation) |
| Male secondary sexual characteristics? | Growth of facial& public hair, hair on armpits and chest, voice deepens, body more muscular, production of sperm begins, growth of penis and testes |