B2: Reproduction in Animals Flashcards
Define reproduction
the process by which living organisms generate new individuals of the same kind as themselves
What structure is this and identify the lables
A- Fallopian tubes (oviducts),
B- Ovaries
C- Uterus
D- cervix
E - Vagina
F - Vulva
G- anus
H - ureter
I - bladder
J- urethra
K- lips(labia)
label the parts shown
A. seminal vesicle
B. prostate gland
C. sperm duct
D. urethra
E. penis
F. testis
G. bladder
H. ureter
I. scrotum
Functions of the listed parts
A: implantation and develpment of the embryo
B: site of fertilization. Moves ova from ovary to uterus
C: formation of the female gametes(ova). Secretes oestrogen and progesterone
D: retains the contents of the uterus during pregancy. Secretes different forms of mucous during the menstrual cycle
E: receives the penis and sperm, and is also the birth canal
F: opening of the vagina
Functions of the listed parts
A. secretes seminal fluid that mixes with sperm
B. secretes prostate fluid that mixes with seminal fliud
C. transfers sperm fron the testes to the urethra
D. carries semen to the outside of the body. Also carries urine to the outside af the body but not at the same time.
E. becomes erect during intercourse and deposits sperm in he vagina.
F. produces sperm and secretes testosterone
G. stores urine
H. transfers urine from the kidneys to the bladder
I. hold the testes at lower temperature than the body temperature
How are gametes produced ?
When cells divide by meiosis
Where is sperm produced ?
Testes
Where are eggs produced ?
Ovaries
What produces cells that are NOT genetically identical?
Meiosis
What is the tail on a sperm cell called ?
Flagellum
What is external fertilisation?
Fertilisation that occurs outside the body
What is internal fertilisation?
Fertilisation that occurs inside the body
What happens when the sperm reaches the ovum ?
the nucleus of the sperm enters the ovum and fuse with the ovums nucleus, thus restoring the diploid number of chromosome
How many chromosomes does each human gamete have ?
Half the normal number • 23
What is fertilisation ?
Fertilisation is the fusion of haploid male and female gametes, restoring diploid number of chromosomes in the zygote
How many chromosome does the zygote (adult cell) have ?
46
where are sperms stored?
the epididymis
What hormone does the placenta secrete and what does it do ?
Progesterone which prevents the embryo from aborting
When do we call the embryo a foetus ?
When it looks human
What is the membrane called that encloses the developing embryo ?
Amnion
What does the amnion secrete and what does it do ?
Amniotic fluid and it protects the developing embryo from bumps and jolts
What does the placenta do
• anchors the embryo • allows the embryo to obtain glucose and oxygen • gets rid of waste products such as carbon dioxide
How is the placenta attached to the embryo ?
By the umbilical cord
How do the materials move between the maternal and the fetal blood ?
Diffusion
Why do the blood supplies not mix ?
The pressure would be too great for the baby
How is the placenta adapted for efficient exchange of substances ?
- it has lots of capillaries
- short distance for diffusion
- large surface area
- high concentration gradient between the mother and the fetus
What is a period ?
when the lining of the uterus sheds from the woman’s body
What is a follicle ?
A fluid filled sack that contains an egg 🍳
What does oestrogen bring about ?
- The repairing and thickening of the uterus lining
- development of the secondary sexual characteristics
What happens to the follicle after it releases an egg ?
It forms a structure in the ovary called a corpus luteum.
Does a corpus luteum do ?
It makes a hormone called progesterone
What does progesterone do ?
Maintains the uterus lining
What takes over the corpus luteum later on in the pregnancy and secretes progesterone ?
The placenta
What is puberty ?
The time that secondary sexual characteristics occur
What controls the development of secondary sexual characteristics ?
Hormones
two types of reproduction
sexual and asexual
What is the male hormone involved in the development of secondary sexual characteristics ?
Testosterone
What is the female hormone involved in the development of secondary sexual characteristics ?
Oestrogen
Secondary sexual characteristics in boys
- Voice deepens
- sperm production begins
- shoulders broaden
- body and pubic hair develops
- genitalia growth
- possible mood swings and acne
Secondary sexual characteristics in girls
- menstrual cycle begins
- pelvis broadens in preparation for pregnancy
- body and pubic hair develop
- breasts, hips and thighs become larger
Describe what happens at the time of puberty
At the time of puberty, the reproductive organs become active and the body takes on its adult form
Sex cell are also known as (1)____________ and are produced by the process of (2)__________. When fertilization occurs, a single cell is formed called a (3)_______. This single cell then divides by (4)________ to become an (5)__________. Offspring of sexual reproduction have genes from both parents and this results in (6) __________.
- gametes
- meiosis
- zygote
- mitosis
- embryo
- variation
which type of reproduction involves only one parent?
asexual reproduction
Compare sexual and asexual reproduction
- sexual reproduction causes variation. Asexual reproduction produces clones, therefore no variation
- one parent needed in asexual reproduction. two parents are needed in sexual reproduction
- asexual reproduction is a rapid process. Sexual reproduction is slow as it involves many more stages.
- sexual reproduction results in a slow increase in populations. Asexual reproduction results in rapid increase in populations
- Offspring from sexual reproduction are dispersed over wide areas while those of asexual reproduction remain close to the parent.
The primary sexual characteristics in girls are (1)________ovaries and the primary sexual characteristics in boys are (2)__________.
- ovaries
- testes
Describe the timing of puberty and the order and rate of the changes
The timing of puberty and the order and rate of the changes varies, but the basic changes are the same for everyone
functions of the sperm duct
The sperm duct carries sperm to the urethra
function of the testes
The testes make sperm
functions of the scrotum
The scrotum keeps the testes outside the body for maximum sperm production
Function of the penis
The penis places sperm into the vagina
The male reproductive organs
The male reproductive organs are:
- The testes
- The scrotum
- The sperm duct
- The seminal vesicle
- The prostate gland
- The urethra
- The penis
function of the fallopian tube (oviduct)
The fallopian tube (oviduct) is where the egg travels to the uterus and may be fertilised
function of the ovary
The ovary is where eggs mature
function of the cervix
The cervix is the entrance to the uterus
functions the uterus (womb)
The uterus (womb) is where the foetus develops
Female reproductive organs: Describe the vagina
The vagina receives sperm during sexual intercourse
The female reproductive organs
The female reproductive organs are:
- The fallopian tube (oviduct)
- The ovary
- The uterus
- The cervix
- The vagina
The main female reproductive hormone
The main female reproductive hormone is oestrogen
What do rising oestrogen levels do?
Rising oestrogen levels trigger the development of the female secondary sexual characteristics
Rising oestrogen levels trigger the development of :
- A growth spurt
- The growth of hair under the arms and pubic hair
- The breasts develop
- The external genitals grow and the skin darkens
- A female pattern of fat is deposited on the hips, buttocks and thighs
Once a girl has gone through puberty, what will she have?
Once a girl has gone through puberty, she will have a monthly menstrual cycle
Once a girl has gone through puberty, she will have a monthly menstrual cycle. Each month, eggs begin to mature in the ovary. What happens at the same time?
At the same time, the uterus produces a thickened lining ready for a pregnancy
Ovulation
Ovulation is the release of a mature egg (ovum) from the ovary
Every 28 days, a mature egg is released. What happens if the egg is not fertilised?
If the egg is not fertilised, around 14 days later, the lining of the uterus is shed along with the egg This is the monthly period and this also takes place at approximately 28-day intervals
What are involved in controlling the menstrual cycle?
Several hormones are involved in controlling the menstrual cycle:
- FSH
- LH
- Oestrogen and progesterone
What does FSH stand for?
FSH stands for follicle stimulating hormone
What does LH stand for?
LH stands for luteinising hormone
The main male reproductive hormone
The main male reproductive hormone is testosterone, produced by the testes
Testosterone
Testosterone is the main male sex hormone that controls the male secondary sexual characteristics at puberty and the production of sperm
When do boys usually go into the first stages of puberty?
Boys usually go into the first stages of puberty slightly later than girls, between the ages of 9 and 15
the 4 hormones that constrol the menstrual cycle are: (1)________
(2) __________
(3) ___________
(4) ____________
- FSH
- LH
- Oestrogen
- Progesterone
Functions of the following hormones:
(1) FSH
(2) LH
(3) Oestrogen
(4) Progesterone
- FSH
- stimulates the development of the the follicle and ova
- Stimulates the follicle to produce oestrogen
- Oestrogen
- stimulates the the uteus lining to thicken and its blood supply to thicken after menstration
- stops the secretion of FSH from the pituitary gland and causes it to secrete LH
- LH
- causes ovulation
- stimulates the corpus luteum to produce progesterone
- Progesterone
* causes thickening and maintenace of the uterus lining
what are the 4 phases of the menstrual cycle
Identify the days corresponding to the phases of the menstrual cycle below
- Day 1-5
- Day 1-13
- Day 14
- Day 15-28
what are the points to consider when discussing the advantages and disadvantages of the different birth control methods?
- failure rate
- prevention of STIs
- cost
- side effects
- permanent or temporary
- need for surgical procedures or not
Birth control Methods
- Barrier: condom and diaphram
- Hormonal: the pill
- Surgical sterilization: vasectomy and tubal ligation
- Natural: rhythm method, withdrawal. abstinence
- Spermicides: creams, jellies and foams
- Intrauterine Devices (IUD)
importance of birth control
- prevents unwanted pregnancy and teenage pregnancy
- decreases maternal deaths
- decreases infant deaths
- controls the number of children per family so each child can be better cared for.
- helps reduce population growth, thus causing less strain on the worlds resources
What hormone represents each graph colour in the diagram below?
yellow - oestrogen
blue - progesterone
green - FSH(follicle stimulating hormone)
red - LH (luteinising Hormone)
what are the labeled structures in the diagram?
A- Placenta
B - Thickened lining of the uterus
C- capillary network in the placenta
D - Villi
E- Amnion
F- Amniotic fluid
G - mucus plug
H - Vagina
I - muscular wall of the uterus
J - umbilical cord
K- embryo or foetus
L - Umbilical vein
M - Umbilical artery
what is the function of the umbilical cord?
- carries deoxygenated blood and waste away from the foetus to the placenta via the umbilical artery
- carries ogygenated blood and nutrients to the foetus via the umbilical vein
Identify the labeled parts
A - Lining of uterus
B - oviduct (fallopian tube)
C- Amnion
D - Amniotic fluid
E - Mucus plug in cerix
F - Umbilical Cord
G - muscular wal of uterus
H - Vagina
I - Embryo or Foetus
J - Placenta
what is a zygote?
A diploid cell resulting form the fusion of 2 haploid cells.
How long is the gestation period in humans?
- about 40 week or 280 days
After fertilization a diploid cell is formed call a (1) ____________. This diplod cell then divides by (2)_________ to form a ball of cells called the (3)_________. This ball of cells then travels down the oviduct to the (4)________, where (5)_________ occurs. This occurs about (6) ____________ days after fertilization. When the embyro looks human it is called a (7)___________. The human features are evident from about (8)__________ weeks.
- zygote
- mitosis
- embryo
- uerus lining
- implantation
- 7-10
- foetus
- 10 weeks
