PPT: The Invisible Living World: Beyond Our Naked Eye | Science Curiosity Class 8 - New NCERT PDF Download

 Page 1


The Invisible Living
World: Beyond Our
Naked Eye
Page 2


The Invisible Living
World: Beyond Our
Naked Eye
What Is a Cell?
Cells are the tiny building blocks of all living
things—plants, animals, and microbes!
Key Parts
Cell Membrane
Controls what enters and exits the cell, like a
security guard at the door.
Cytoplasm
Jelly-like area where life processes happen,
like a busy shopping mall.
Nucleus
Directs all cell activities, like a control center
or brain of the cell.
Did You Know? Cells are too small to see without a
microscope!
Page 3


The Invisible Living
World: Beyond Our
Naked Eye
What Is a Cell?
Cells are the tiny building blocks of all living
things—plants, animals, and microbes!
Key Parts
Cell Membrane
Controls what enters and exits the cell, like a
security guard at the door.
Cytoplasm
Jelly-like area where life processes happen,
like a busy shopping mall.
Nucleus
Directs all cell activities, like a control center
or brain of the cell.
Did You Know? Cells are too small to see without a
microscope!
1
1 6 6 5
Robert Hooke observed "cells" in cork using a
microscope. He named them after the
honeycomb-like appearance that reminded him
of monastery cells.
2
1 6 7 0 s
Antonie van Leeuwenhoek, now
known as the Father of
Microbiology, used better lenses
to see living cells like bacteria for
the first time.
Page 4


The Invisible Living
World: Beyond Our
Naked Eye
What Is a Cell?
Cells are the tiny building blocks of all living
things—plants, animals, and microbes!
Key Parts
Cell Membrane
Controls what enters and exits the cell, like a
security guard at the door.
Cytoplasm
Jelly-like area where life processes happen,
like a busy shopping mall.
Nucleus
Directs all cell activities, like a control center
or brain of the cell.
Did You Know? Cells are too small to see without a
microscope!
1
1 6 6 5
Robert Hooke observed "cells" in cork using a
microscope. He named them after the
honeycomb-like appearance that reminded him
of monastery cells.
2
1 6 7 0 s
Antonie van Leeuwenhoek, now
known as the Father of
Microbiology, used better lenses
to see living cells like bacteria for
the first time.
Plant vs. Animal Cells
Plant Cells
Rigid cell wall for protection and support
Large central vacuole for storage
Chloroplasts for photosynthesis
Rectangular or box-like shape
Nucleus often pushed to one side
Animal Cells
No cell wall, only flexible membrane
Small or no vacuoles
No chloroplasts
Irregular or rounded shape
Nucleus usually in the center
Page 5


The Invisible Living
World: Beyond Our
Naked Eye
What Is a Cell?
Cells are the tiny building blocks of all living
things—plants, animals, and microbes!
Key Parts
Cell Membrane
Controls what enters and exits the cell, like a
security guard at the door.
Cytoplasm
Jelly-like area where life processes happen,
like a busy shopping mall.
Nucleus
Directs all cell activities, like a control center
or brain of the cell.
Did You Know? Cells are too small to see without a
microscope!
1
1 6 6 5
Robert Hooke observed "cells" in cork using a
microscope. He named them after the
honeycomb-like appearance that reminded him
of monastery cells.
2
1 6 7 0 s
Antonie van Leeuwenhoek, now
known as the Father of
Microbiology, used better lenses
to see living cells like bacteria for
the first time.
Plant vs. Animal Cells
Plant Cells
Rigid cell wall for protection and support
Large central vacuole for storage
Chloroplasts for photosynthesis
Rectangular or box-like shape
Nucleus often pushed to one side
Animal Cells
No cell wall, only flexible membrane
Small or no vacuoles
No chloroplasts
Irregular or rounded shape
Nucleus usually in the center
Variation in shape and structure of cells
Cell shapes are perfectly matched to their jobs in the organism—just like tools are designed for specific tasks!
Nerve Cells
Long and branched like tree roots to
carry messages quickly across long
distances in your body.
Muscle Cells
Spindle-shaped and stretchy for
movement and contraction when you
walk, run, or move.
Plant Transport Cells
Tube-like to efficiently move water and
nutrients up from roots to leaves and
throughout the plant.