B10 - Reproduction Flashcards
Asexual reproduction is the process of reproduction that forms genetically identical offspring from only
one parent
What is the process of reproduction that forms genetically identical offsprings from one parent
Asexual reproduction
What are the four key features in Asexual reproduction
Cells divide via mitosis
Offsprings are cloned
There is no gamete fusion
Only one parent is involved
What are the Advantages and Disadvantages of Asexual reproduction
Advantages: Only one parent is needed so no need for a second one
Large number of offsprings can be produced quickly
All offsprings are produced identically
Disadvantages: Lack of variation in offspring means that a change in condition will affect all organisms equally
They are not suited for other environments and are not diverse. Can be prone to diseases easier.
What is the process of sexual reproduction
when the nuclei of two gametes (sex cells) fuse to form a zygote (fertilization), producing offspring that are genetically different to one another
what are the 4 key factors of sexual reproduction
Male and female gametes fuse
Offsprings are non-identical
Two parents are required for the process to occur
Cells divide via meiosis
What are the Advantages and Disadvantages of sexual reproduction
Advantages: Variation in off spring meaning a population is more likely to survive to environmental changes
Selective breeding can occur
Disadvantages: Requires a second parent
Mutations can be produced which will be harmful for a population
Zygote nuclei are
diploid meaning they contain two complete sets of chromosomes one from each parent
Gamete nuclei are
haploid meaning they contain half the number of chromosomes found in a normal cell
What is the male part of the flower called
the stamen
What is the female part of the flower called
the carpel
What makes up the stamen
the anther and filament
What makes up the carpel
the stigma, style, ovary and ovule
What does the sepal do
it protects the flower bud when it develops
Pollen grains develop inside the
anther
What is the function of the filament
to hold the anther
The stigma is part of the carpel where
the pollen lands during pollination
The style is the tube which
the pollen travels down
The ovary is responsible for
protecting the female gamete from the outside
Ovary contains one or more
ovules
Each ovule contains an
egg sac
What is the function of the petals
to attract insects for pollination
What is the process in transferring pollen from the stigma to the carpel called
pollination
What are the 2 ways in which pollination can happen
wind and insect pollination
What is self pollination
the occurrence when pollen from an anther is transferred to the stigma of the same flower. The offsprings produced are identical to the parent
Advantages and disadvantages of self pollination
Advantages: If plants cannot reproduce by cross pollination than they can self pollinate
Disadvantages: Lack of variation meaning less chance of survival in a change in condition or environment
What is cross pollination
the transfer of pollen from anther of one flower to the stigma of another flower
Advantages and disadvantages of cross pollination
Advantages: More genetic variation meaning higher change of survival if change of condition or environment
Disadvantages: There can be no pollinators and may take a long time
What is the process of fertilisation
when a female and male gamete fuse
What are some features of wind pollinated plants
Small or even no petals No scent Many anthers that hang out the plant Stigmas are large and feathery Pollen grains are smooth Pollen is lightweight
What are some features of insect pollinated plants
Large petals for insects to land on Bright colored to attract insects Scent to attract insects Few small anthers inside the flower Pollen grains are sticky and spiky pollen is heavy
What is germination
when a seed coat breaks open and the embryo starts to grow and develop in a new plant
What are the conditions required for germination
temperature, moisture and oxygen
What do the testes produce
male hormones (testosterone) and sperm
The testes are protected by the
scrotum which regulates sperm temperature
Sperm duct function
moves sperm from testes to urethra
The prostate gland produces substances
that are added to the sperm to make semen
Eggs are stored in the
ovaries and travel down the oviducts to the uterus
what is the cervix
the opening at the bottom of the uterus leading to the vagina
vagina is where
sperm is deposited
Fertilization takes place in
oviducts
After fertilization the egg travels toward the
uterus and takes 3 days
what is the development of the embryo after 3 months
a fetus
the fetus develops inside a bag of
amniotic fluid that protects the fetus
AIDS is a disease of the immune system caused by the virus
HIV
To prevent the transmission of HIV we use
contraceptives like condoms
What are the stages of the menstrual cycle
1 - 4 days: The uterus lining breaks down resulting in a period
4 - 14 days: The uterus lining starts to build up again into a thick, spongy layer full of blood vessels.
14 days: Ovulation happens. This is when an egg is released from one of the ovaries.
15 - 28 days: The uterus lining is maintained ready for a fertilized egg. If no fertilized egg is attached to the uterus lining, the lining breaks down and the cycle begins again.
What are the stages of pregnancy
Zygote forms and starts to divide to form a ball of cells
Once the ball forms its called an embryo and implants itself to the wall of the uterus
Placenta forms between the embryo and the wall of the uterus
Umbilical cord provides nutrients to the baby
Foetus is called after 6 weeks of fertilization
