Functions: Ovary: (l) Production of female hormone/oestrogen and progesterone. (ii) Production of female gamete,/egg/germ cell. Oviduct: (l) Transfer of female gamete from the ovary. (ii) Site of fertilization. Uterus: (l) Implantation of Zygote/embryo. (ii) Nourishment of developing embryo. . PlaceRead more
Functions:
Ovary: (l) Production of female hormone/oestrogen and progesterone.
(ii) Production of female gamete,/egg/germ cell.
Oviduct: (l) Transfer of female gamete from the ovary.
(ii) Site of fertilization.
Uterus: (l) Implantation of Zygote/embryo.
(ii) Nourishment of developing embryo.
. Placenta is a special disc like tissue embedded in the mother’s uterine wall and connected to the foetus/embryo.
.Placenta provides a large surface area for glucose and oxygen/nutrients to pass from the mother’s blood to the embryo/foetus.
. Carbon has 4 electrons in its outermost shell, and needs to gain or lose 4 electrons to attain noble gas configuration. . Losing or gaining 4 electrons is not possible due to energy considerations; hence it shares electrons to form covalent bonds. .Two reasons {or large number of carbon compounds:Read more
. Carbon has 4 electrons in its outermost shell, and needs to gain or lose 4 electrons to attain noble gas configuration.
. Losing or gaining 4 electrons is not possible due to energy considerations; hence it shares electrons to form covalent bonds.
.Two reasons {or large number of carbon compounds:
Catenation: The unique ability of carbon to form bonds with other atoms of carbon giving rise to long chains of different types of compounds.
. Tetravalency: Since carbon has a valency of 4, it is capable of bonding with four other atoms of carbon or atoms of elements like oxygen, hydrogen, nitrogen, sulphur, chlorine, etc.
The reason for the formation of strong bonds by carbon is its small size which enables the nucleus to hold on to the shared pairs of electrons strongly.
The candidate may choose any two of the following rays: (i) A ray parallel to the principal axis, after reflection, will pass through the principal focus of a concave mirror. (ii) A ray passing through the principal focus of a concave mirror after reflection will emerge parallel to the principal axiRead more
The candidate may choose any two of the following rays:
(i) A ray parallel to the principal axis, after reflection, will pass through the principal focus
of a concave mirror.
(ii) A ray passing through the principal focus of a concave mirror after reflection will emerge
parallel to the principal axis.
(iii) A ray passing through the center of curvature of a concave mirror after reflection is
reflected back along the same path.
(iv) A ray incident obliquely to the principal axis towards the pole of a concave mirror is reflected obliquely; making equal angles with the principal axis
Using the ray number (iii) and (iv) we can draw the required ray diagram.
Acquired Traits:- (l) Does not bring about change in the DNA of the germ cell. (ii) Cannot be passed on to the progeny. (iii) Cannot direct evolution Examples: Acquiring knowledge, loss of weight or any other example. Inherited Traits:- (l) Brings about change in the DNA of the germ cell. (ii) Can bRead more
Acquired Traits:- (l) Does not bring about change in the
DNA of the germ cell.
(ii) Cannot be passed on to the progeny.
(iii) Cannot direct evolution
Examples: Acquiring knowledge, loss of weight or any other example.
Inherited Traits:- (l) Brings about change in the DNA of the germ cell.
(ii) Can be passed on to the progeny.
(iii) Can direct evolution.
List two observations which you make when you add a pinch of sodium hydrogen carbonate to acetic acid in a test tube. Write chemical equation for the reaction that occurs.
(l) Brisk effervescence (ii) Evolution of a colourless gas NaHCO3 + CH3COOH ------- CH3COONa + H2O + CO2
(l) Brisk effervescence
See less(ii) Evolution of a colourless gas
NaHCO3 + CH3COOH ——- CH3COONa + H2O + CO2
Write the functions of the following in human female reproductive system: Ovary, Oviduct, Uterus How does the embryo get nourishment inside the mother’s body? Explain in brief.
Functions: Ovary: (l) Production of female hormone/oestrogen and progesterone. (ii) Production of female gamete,/egg/germ cell. Oviduct: (l) Transfer of female gamete from the ovary. (ii) Site of fertilization. Uterus: (l) Implantation of Zygote/embryo. (ii) Nourishment of developing embryo. . PlaceRead more
Functions:
Ovary: (l) Production of female hormone/oestrogen and progesterone.
(ii) Production of female gamete,/egg/germ cell.
Oviduct: (l) Transfer of female gamete from the ovary.
(ii) Site of fertilization.
Uterus: (l) Implantation of Zygote/embryo.
(ii) Nourishment of developing embryo.
. Placenta is a special disc like tissue embedded in the mother’s uterine wall and connected to the foetus/embryo.
.Placenta provides a large surface area for glucose and oxygen/nutrients to pass from the mother’s blood to the embryo/foetus.
See lessExplain why carbon forms compounds mainly by covalent bond. Explain in brief two main reasons for carbon forming a large number of compounds. Why does carbon form strong bonds with most other elements?
. Carbon has 4 electrons in its outermost shell, and needs to gain or lose 4 electrons to attain noble gas configuration. . Losing or gaining 4 electrons is not possible due to energy considerations; hence it shares electrons to form covalent bonds. .Two reasons {or large number of carbon compounds:Read more
. Carbon has 4 electrons in its outermost shell, and needs to gain or lose 4 electrons to attain noble gas configuration.
See less. Losing or gaining 4 electrons is not possible due to energy considerations; hence it shares electrons to form covalent bonds.
.Two reasons {or large number of carbon compounds:
Catenation: The unique ability of carbon to form bonds with other atoms of carbon giving rise to long chains of different types of compounds.
. Tetravalency: Since carbon has a valency of 4, it is capable of bonding with four other atoms of carbon or atoms of elements like oxygen, hydrogen, nitrogen, sulphur, chlorine, etc.
The reason for the formation of strong bonds by carbon is its small size which enables the nucleus to hold on to the shared pairs of electrons strongly.
To construct ray diagrams, two rays of light are generally so chosen that it is easy to determine their directions after reflection from a mirror. Choose two such rays and state the path/direction of these rays after reflection from a concave mirror. Use these two rays to find the position and nature of the image of an object placed at a distance of 8 cm from a concave mirror of focal length 12 cm.
The candidate may choose any two of the following rays: (i) A ray parallel to the principal axis, after reflection, will pass through the principal focus of a concave mirror. (ii) A ray passing through the principal focus of a concave mirror after reflection will emerge parallel to the principal axiRead more
The candidate may choose any two of the following rays:
(i) A ray parallel to the principal axis, after reflection, will pass through the principal focus
of a concave mirror.
(ii) A ray passing through the principal focus of a concave mirror after reflection will emerge
parallel to the principal axis.
(iii) A ray passing through the center of curvature of a concave mirror after reflection is
reflected back along the same path.
(iv) A ray incident obliquely to the principal axis towards the pole of a concave mirror is reflected obliquely; making equal angles with the principal axis
Using the ray number (iii) and (iv) we can draw the required ray diagram.
See lessList in tabular form, two distinguishing features between the acquired traits and the inherited traits with one example of each.
Acquired Traits:- (l) Does not bring about change in the DNA of the germ cell. (ii) Cannot be passed on to the progeny. (iii) Cannot direct evolution Examples: Acquiring knowledge, loss of weight or any other example. Inherited Traits:- (l) Brings about change in the DNA of the germ cell. (ii) Can bRead more
Acquired Traits:- (l) Does not bring about change in the
DNA of the germ cell.
(ii) Cannot be passed on to the progeny.
(iii) Cannot direct evolution
Examples: Acquiring knowledge, loss of weight or any other example.
Inherited Traits:- (l) Brings about change in the DNA of the germ cell.
(ii) Can be passed on to the progeny.
(iii) Can direct evolution.
Examples: Skin colour, colour of the eyes.
See less