Exact location of important structures and their function
Structure Location Function
Chapter 2: Structure of Chromosomes, Cell Cycle and Cell Division
Centromere Point of attachment of Helps in the attachment of
two sister chromatids. chromosomes to spindle fibres.
Chapter 5: Transpiration
Lenticels On the surfaces of woody Diffusion of gases for
stems/old stems. photosynthesis and respiration.
Hydathode On the margins of leaves Tips Water loss through guttation or
of veins in a leaf. exudation.
Chapter 6: Photosynthesis
Chloroplasts In the cytoplasm of plant Traps solar energy for
cells/mesophyll cells located photosynthesis.
between the upper and lower
epidermis of leaves/guard cells of
stomata.
Chlorophyll In the wall of the thylakoids Absorbs light energy and helps
present in the chloroplast. in photolysis during the light-
dependent phase of
photosynthesis.
Cuticle Waxy layer on the surfaces Being transparent, it allows
of leaves. sunlight to reach the mesophyll
of leaves. Prevents evaporation
of water from the leaf
surface.
Thylakoids Flattened sacs are arranged Site of the light-dependent
like piles in the stroma of the phase/light reaction of
chloroplast. photosynthesis.
Stroma Matrix/Ground substance of Site of light-independent
chloroplast. phase/biosynthetic phase
of photosynthesis.
Stomata In all green plants, stomata are Stomatal opening and closure
found in the epidermis of leaves, help the gaseous exchange
stems, and other parts. between the plant and its
surroundings.
, It helps transpire and remove
excess water in the form of
water vapour.
Stomatal closure at night
prevents water from escaping
through pores.
Chapter 8: The Circulatory System
Tricuspid valve At the aperture between the Maintains unidirectional flow of
(Right right auricle and right ventricle. deoxygenated blood from the
atrioventricular right auricle to the right
valve) ventricle.
Bicuspid valve At the aperture between the Maintains unidirectional flow of
(Mitral valve) left auricle and left ventricle. oxygenated blood from the left
atrium to the left ventricle.
Pulmonary semilunar At the opening of the right Maintains unidirectional flow of
valves ventricle into the pulmonary deoxygenated blood from the
artery. right ventricle into the
pulmonary artery.
Aortic semilunar valves At the point of origin of the Prevents backflow of
aorta from the left ventricle. oxygenated blood from
the aorta into the left
ventricle.
Coronary artery Arises from base of the Supplies oxygenated blood
aorta. to the heart
muscles/walls of the
heart.
Spleen In the abdomen, behind the Acts as a blood reservoir,
stomach, and above the left produces lymphocytes, and
kidney. destroys worn-out red blood
cells.
In an embryo, it produces RBCs.
Pacemaker In the walls of the right auricle The impulse or command that
near the opening of the starts the heartbeat arises in
superior vena cava. the pacemaker.
Chapter 9: The Excretory System
Kidneys In the abdominal region, one is Primary excretory organs/
on either side of the produces urine/removal of
Structure Location Function
Chapter 2: Structure of Chromosomes, Cell Cycle and Cell Division
Centromere Point of attachment of Helps in the attachment of
two sister chromatids. chromosomes to spindle fibres.
Chapter 5: Transpiration
Lenticels On the surfaces of woody Diffusion of gases for
stems/old stems. photosynthesis and respiration.
Hydathode On the margins of leaves Tips Water loss through guttation or
of veins in a leaf. exudation.
Chapter 6: Photosynthesis
Chloroplasts In the cytoplasm of plant Traps solar energy for
cells/mesophyll cells located photosynthesis.
between the upper and lower
epidermis of leaves/guard cells of
stomata.
Chlorophyll In the wall of the thylakoids Absorbs light energy and helps
present in the chloroplast. in photolysis during the light-
dependent phase of
photosynthesis.
Cuticle Waxy layer on the surfaces Being transparent, it allows
of leaves. sunlight to reach the mesophyll
of leaves. Prevents evaporation
of water from the leaf
surface.
Thylakoids Flattened sacs are arranged Site of the light-dependent
like piles in the stroma of the phase/light reaction of
chloroplast. photosynthesis.
Stroma Matrix/Ground substance of Site of light-independent
chloroplast. phase/biosynthetic phase
of photosynthesis.
Stomata In all green plants, stomata are Stomatal opening and closure
found in the epidermis of leaves, help the gaseous exchange
stems, and other parts. between the plant and its
surroundings.
, It helps transpire and remove
excess water in the form of
water vapour.
Stomatal closure at night
prevents water from escaping
through pores.
Chapter 8: The Circulatory System
Tricuspid valve At the aperture between the Maintains unidirectional flow of
(Right right auricle and right ventricle. deoxygenated blood from the
atrioventricular right auricle to the right
valve) ventricle.
Bicuspid valve At the aperture between the Maintains unidirectional flow of
(Mitral valve) left auricle and left ventricle. oxygenated blood from the left
atrium to the left ventricle.
Pulmonary semilunar At the opening of the right Maintains unidirectional flow of
valves ventricle into the pulmonary deoxygenated blood from the
artery. right ventricle into the
pulmonary artery.
Aortic semilunar valves At the point of origin of the Prevents backflow of
aorta from the left ventricle. oxygenated blood from
the aorta into the left
ventricle.
Coronary artery Arises from base of the Supplies oxygenated blood
aorta. to the heart
muscles/walls of the
heart.
Spleen In the abdomen, behind the Acts as a blood reservoir,
stomach, and above the left produces lymphocytes, and
kidney. destroys worn-out red blood
cells.
In an embryo, it produces RBCs.
Pacemaker In the walls of the right auricle The impulse or command that
near the opening of the starts the heartbeat arises in
superior vena cava. the pacemaker.
Chapter 9: The Excretory System
Kidneys In the abdominal region, one is Primary excretory organs/
on either side of the produces urine/removal of
