UNIT 1 1.1 Plant and animal cells
Preparation of a Microscopic Slide
Viewing under a light Microscope
Cell Recording observation
Structure of Light microscope
Different types of cells observed under an
Structure ordinary Microscope
Animal cells:
Difference between Animals and Plant
and cells
Similarity between Animal and Plant cells
Components of Cell
Organization 1.2 Specialized cells, tissues and organs
R.B.C
Lymphocytes
Phagocytes
Root hairs
Xylem vessels
,1.1 Plant and animal cells
It is a basic unit of structure and function of all living things (Except Viruses). New cells come from
division of old cells.
Preparation of a Microscopic Slide:
Preparation of an onion epidermal slide:
Cut a piece of onion with the help of a razor.
Remove the epidermis with the help of forceps.
Place the epidermis in the canter of a slide.
Pour few drops of Dye / Stain on it.
Place a cover glass on the mounted material in such a way that the cover glass is held on the
pointed tip of a needle and gradually lower it down. So the air bubbles are not trapped.
Remove the extra stain using blotting paper.
Viewing under a light Microscope:
Place the slide on the stage.
Turn on the lamp.
Adjust the power of the objective
Looking through the eye piece focus the image by moving adjustment knobs.
Recording observation:
Take a photomicrograph.
Draw the outline of the image seen.
Structure of Light microscope
Label different parts
Difference between Animals and Plant cells:
Cell wall is absent in animal cell whereas plant cells have cell wall.
Sap vacuole is absent in animal cell whereas sap vacuole is present in plant cell.
Chloroplast is absent in an animal cell where as it is present in a plant cell.
Nucleus is present in the center in an animal cell where as it is in plant cells slightly on its side.
Size of plant cell is big whereas the size of cell is small in animals.
Starch is reserve food in a plant cell whereas glycogen in an animal cell.
Similarity between Animal and Plant cells:
They both contain cell membrane.
They both have cytoplasm.
They both have nucleus in them.
Components of Cell
Cell wall:
It is found in plant cells. It is composed of cellulose (A carbohydrate). It is rigid dead layer. It is fully
permeable layer which protects a plant cell from bursting and maintains its shape.
Cell Membrane:
It is a partially permeable membrane. Outer most boundary in animal cells. It is beneath the cell wall in
, a plant cell. Prevents mixing up of the contents of various cells together. Controls the inward and
outward movement of substances.
Cytoplasm:
It is a jelly like substance which covers the space between cell membrane and the nuclear membrane.
It is a site for chemical reactions e.g. Respiration.
Nucleus:
It is densely stain region in the center of an animal cell and slightly away from the center in a plant cell.
It consists of a nuclear membrane which is partially permeable. It also contains chromosomes.
Chromosomes carry the hereditary materials. Nucleus controls the division of cells.
Chloroplast:
It is found in mesophyll and guard cells in a plant cell. It is double membrane bound cell organelle. Non
Living components in the cytoplasm are called inclusions e.g. Starch. Living components in the
cytoplasm are called organelles. Chloroplast contains green pigment called chlorophyll embedded in it.
Chlorophyll traps the light energy and converted into chemical energy. This chemical energy is used in
formation of carbohydrates from CO2& H2O by photosynthesis
Magnification
The following figure is a photomicrograph of a white blood cell.
X 900
Draw and label the white blood cell shown in figure 1.1
Measure the Width of the cell in the figure = mm
Measure the Width of the cell in the diagram = mm
Magnification =
Magnification = X
1.2 Specialized cells, tissues and organs:
Cells that have specific shape and perform some specific function are called specialized cells.
R.B.C:
Structural features
They are tiny.
They are flat.
They are biconcave.
They lack nucleus.
They contain hemoglobin.
Adaptation of structure to function:
The advantage of being tiny is that it has large surface so more
efficient exchange of oxygen. Being flat they have more surface area
and exchange of gases is easy. Being flat they can pass through
narrow capillaries. Lack of nucleus provides more room for
hemoglobin. Hemoglobin combines reversibly with oxygen to form oxy-
hemoglobin.
Lymphocytes:
Structural features
Spherical cell.
Large central nucleus.
To release anti bodies (proteins) to fight against pathogens.
Adaptation of structure to function
, The antibodies are specific in their function. They are produced in wide range against variety of
pathogens. Many copies of genes are needed for the formation of wide range of antibodies. The
lymphocytes have large nucleus to contain many copies of genes.
Phagocytes
Structural features
Irregular shape
Lobed nucleus
Adaptation of structure to function
Phagocytes can squeeze out of the blood capillaries through narrow pores.
Root hairs
Structural features
Elongated
Contain cell membrane
Cell wall present
Cytoplasm present
Adaptation of structure to function
Being elongated increases surface area to volume ratio for absorption of water and mineral ions. Cell
membrane controls the movement of substances into and out of cell. It maintains concentration
gradient between inside and outside. As water moves into the cells it exerts hydrostatic pressure on
the cell. Cell wall prevents cell from bursting. Respiration in cell cytoplasm releases energy from sugars
which is used for active uptake of mineral ions.
Xylem vessels
, Surface View Cross Sectional View
Structural features
Cylindrical cells
Hollow
No cross walls
Lack cytoplasm and lack nucleus
Lignified cell walls
Adaptation of structure to function
Being cylindrical they are joined end to end to extend from roots to leaves. Lack of nucleus and
cytoplasm reduces resistance offered to flow of water and minerals. Lignified walls provide strength
which provides mechanical support to the plant.
, UNIT 2 2.1 Diffusion
Diffusion gradient
Importance of diffusion
Diffusion and 2.2 Osmosis
Osmosis
Osmosis
Water potential
Behavior of animal cells in solution of
different concentration
Behavior of plant cells in solutions of
different concentrations
2.3 Active Transport
Surface area to volume ratio
Volume:
Preparation of a Microscopic Slide
Viewing under a light Microscope
Cell Recording observation
Structure of Light microscope
Different types of cells observed under an
Structure ordinary Microscope
Animal cells:
Difference between Animals and Plant
and cells
Similarity between Animal and Plant cells
Components of Cell
Organization 1.2 Specialized cells, tissues and organs
R.B.C
Lymphocytes
Phagocytes
Root hairs
Xylem vessels
,1.1 Plant and animal cells
It is a basic unit of structure and function of all living things (Except Viruses). New cells come from
division of old cells.
Preparation of a Microscopic Slide:
Preparation of an onion epidermal slide:
Cut a piece of onion with the help of a razor.
Remove the epidermis with the help of forceps.
Place the epidermis in the canter of a slide.
Pour few drops of Dye / Stain on it.
Place a cover glass on the mounted material in such a way that the cover glass is held on the
pointed tip of a needle and gradually lower it down. So the air bubbles are not trapped.
Remove the extra stain using blotting paper.
Viewing under a light Microscope:
Place the slide on the stage.
Turn on the lamp.
Adjust the power of the objective
Looking through the eye piece focus the image by moving adjustment knobs.
Recording observation:
Take a photomicrograph.
Draw the outline of the image seen.
Structure of Light microscope
Label different parts
Difference between Animals and Plant cells:
Cell wall is absent in animal cell whereas plant cells have cell wall.
Sap vacuole is absent in animal cell whereas sap vacuole is present in plant cell.
Chloroplast is absent in an animal cell where as it is present in a plant cell.
Nucleus is present in the center in an animal cell where as it is in plant cells slightly on its side.
Size of plant cell is big whereas the size of cell is small in animals.
Starch is reserve food in a plant cell whereas glycogen in an animal cell.
Similarity between Animal and Plant cells:
They both contain cell membrane.
They both have cytoplasm.
They both have nucleus in them.
Components of Cell
Cell wall:
It is found in plant cells. It is composed of cellulose (A carbohydrate). It is rigid dead layer. It is fully
permeable layer which protects a plant cell from bursting and maintains its shape.
Cell Membrane:
It is a partially permeable membrane. Outer most boundary in animal cells. It is beneath the cell wall in
, a plant cell. Prevents mixing up of the contents of various cells together. Controls the inward and
outward movement of substances.
Cytoplasm:
It is a jelly like substance which covers the space between cell membrane and the nuclear membrane.
It is a site for chemical reactions e.g. Respiration.
Nucleus:
It is densely stain region in the center of an animal cell and slightly away from the center in a plant cell.
It consists of a nuclear membrane which is partially permeable. It also contains chromosomes.
Chromosomes carry the hereditary materials. Nucleus controls the division of cells.
Chloroplast:
It is found in mesophyll and guard cells in a plant cell. It is double membrane bound cell organelle. Non
Living components in the cytoplasm are called inclusions e.g. Starch. Living components in the
cytoplasm are called organelles. Chloroplast contains green pigment called chlorophyll embedded in it.
Chlorophyll traps the light energy and converted into chemical energy. This chemical energy is used in
formation of carbohydrates from CO2& H2O by photosynthesis
Magnification
The following figure is a photomicrograph of a white blood cell.
X 900
Draw and label the white blood cell shown in figure 1.1
Measure the Width of the cell in the figure = mm
Measure the Width of the cell in the diagram = mm
Magnification =
Magnification = X
1.2 Specialized cells, tissues and organs:
Cells that have specific shape and perform some specific function are called specialized cells.
R.B.C:
Structural features
They are tiny.
They are flat.
They are biconcave.
They lack nucleus.
They contain hemoglobin.
Adaptation of structure to function:
The advantage of being tiny is that it has large surface so more
efficient exchange of oxygen. Being flat they have more surface area
and exchange of gases is easy. Being flat they can pass through
narrow capillaries. Lack of nucleus provides more room for
hemoglobin. Hemoglobin combines reversibly with oxygen to form oxy-
hemoglobin.
Lymphocytes:
Structural features
Spherical cell.
Large central nucleus.
To release anti bodies (proteins) to fight against pathogens.
Adaptation of structure to function
, The antibodies are specific in their function. They are produced in wide range against variety of
pathogens. Many copies of genes are needed for the formation of wide range of antibodies. The
lymphocytes have large nucleus to contain many copies of genes.
Phagocytes
Structural features
Irregular shape
Lobed nucleus
Adaptation of structure to function
Phagocytes can squeeze out of the blood capillaries through narrow pores.
Root hairs
Structural features
Elongated
Contain cell membrane
Cell wall present
Cytoplasm present
Adaptation of structure to function
Being elongated increases surface area to volume ratio for absorption of water and mineral ions. Cell
membrane controls the movement of substances into and out of cell. It maintains concentration
gradient between inside and outside. As water moves into the cells it exerts hydrostatic pressure on
the cell. Cell wall prevents cell from bursting. Respiration in cell cytoplasm releases energy from sugars
which is used for active uptake of mineral ions.
Xylem vessels
, Surface View Cross Sectional View
Structural features
Cylindrical cells
Hollow
No cross walls
Lack cytoplasm and lack nucleus
Lignified cell walls
Adaptation of structure to function
Being cylindrical they are joined end to end to extend from roots to leaves. Lack of nucleus and
cytoplasm reduces resistance offered to flow of water and minerals. Lignified walls provide strength
which provides mechanical support to the plant.
, UNIT 2 2.1 Diffusion
Diffusion gradient
Importance of diffusion
Diffusion and 2.2 Osmosis
Osmosis
Osmosis
Water potential
Behavior of animal cells in solution of
different concentration
Behavior of plant cells in solutions of
different concentrations
2.3 Active Transport
Surface area to volume ratio
Volume:
