1). Write a brief note on mitochondria.
These are red shaped or spherical in shape. They provide energy to the cell for various activities.
Mitochondria is also called the powerhouse of cell.
2). Cell in the living organisms are
Simple structure /. Complex structure / not definite in structure / unorganised structure
They are complex structure as each component of them has a different function
3). An example of multicellular organism is
Amoeba / paramecium / euglena / Spirograph
Spirograph it is made up of many cells.
4 ) Name the living substances of the cell.
Protoplasm
5) the undefined nuclear region in bacteria is
Nucleoid / nucleus/ chromosome / nucleoli should
Nucleoid in prokaryotes the nucleoid is an irregularly shaped region within the cell where the
genetic material is localised. The nuclei acid is a circular , double stranded piece of DNA and
multiple copies may exist. This method of genetic storage can be contrasted against that of the
eukaryotes where DNA is packed into chromosomes and sequestered within a membrane bound
organelles called the nucleus
6. Largest cell which can be observed with an unaided eye is a/an
Ostrich egg/ nerve cell / green algae character /elephant egg
Ostrich it’s diameter is 170 mm
7. Smallest cell in size observed in bacteria is
Bacillus/ Cyanobacteria/ mycoplasma/acetobacter
Mycoplasma size 0.1 micron ( ten thousandth part of a millimetre)
8. The cells that receive and transfer messages in the body
Muscle cells / cheek cells/nerve cell/epithelial cells
Nerve cell these cells receive and transfer messages in the to control and coordinate the working
of different be parts
9. The largest vacuoles can be found in
Amoeba/ plants / plants and animals/ bacteria
Plant cells have larger and animal cells have fewer vacuoles
10. Differentiate between plant and animal cell.
Plant cell: 1 Larger in size 2 Plastids are present 3 Cell wall is present
4 Vacuoles are large in size and more in number 5 They have fixed and regular shape
6 Centrosomes are absent
Animal cell: 1
11. The largest cell is the egg of a/an
Ostrich
The egg of an ostrich has the largest measuring of 170 x 130 mm in size
12. Different tissues join to form a
Organ
13. The partitioned boxes in the slice of the cork appear like
Honey comb
They look like the compartments of a honey comb, the hexagonal wax cells are made by
honeybees.
14. Write three differences between prokaryotic and eukaryotic cells.
Prokaryotic cells:
1 The cells having nuclear material without nuclear membrane are called prokaryotic cells.
2. No cell organelle is present.
3. Ex. Bacteria and blue green algae
Eukaryotic cells:
1. The cells have a well organised nucleus with a nuclear membrane are called eukaryotic cells.
2. All cell organelles like mitochondria, chloroplast, ER etc. are present in eukaryotic cells.
3. Ex. Higher organisms
15. Elements mainly present in protoplasm are
Protoplasm is mainly made up of C, H, O & N. These elements later on get involved in the
formation of molecules of life, like carbohydrates, proteins, fats, nucleic acids and mineral salts.
16. Write the function of the following:
Mitochondria- provide energy to the cell for carrying out various activities.
Chromosomes- transfer the characters from parents to next generations.
Plastids- the largest cell organelle containing pigments. They give colour to flowers and fruits,
which help in pollination.
17. Give two examples of prokaryotes.
Bacteria and blue green algae
18. The thread line structures present in the nucleus are known as
Chromosomes
They carry genes on them that transfer the characters from parents to the next generation.
19. Cells in the living organisms are
Complex structures
They are complex structures, as each component of them has a different function.
20. Which organelle is called control centre of the activities of the cell?
Nucleus
21. The main difference between trees and herbs is
Size
Both plants and herbs have similar parts but are different in their size. The type of the stem, the
branches and the distance of the branches from the ground are the criterion to differentiate
between herbs, shrubs and trees.
22. The structure responsible for the transfer of characters from the parents to next generation is
Chromosomes
23. The jelly like substance present between the nucleus and cell membrane is called
Cytoplasm
Cytoplasm is a gelatinous, semi-transparent fluid that fills most cells, which are present in
between the nucleus and cell membrane.
24. A cellular structure having pores is a
Cell membrane
A cell membrane has tiny holes. This regulates the flow of substances into the cell.
25. The shape of a body of an Ameoba is
Irregular
The shape of the body of an Ameoba is irregular as it keeps on changing its shape.
26. The plastids containing green pigments is called
Chloroplast
It provides green colour to the leaves of the plants and help in the process of photosynthesis.
27. Euglena is a unicellular organism processing
Flagella
28. Mention the layer outside the plasma membrane of a plant cell
Cell wall
29. Give two examples of unicellular organisms.
Ameoba and Paramecium
30. The part of the cell that controls all activities of the cell is the
Nucleus
The nucleus is a membrane bound structure that contains the cell’s hereditary information and
controls the cell’s growth and reproduction.
31. Name four elements, which form major part of protoplasm
Carbon, hydrogen, oxygen, and nitrogen
32. Name the largest organelle present in the cell
Vacuoles
33. The pseudopodia in the body of an Ameoba
are temporary organs
They appear and disappear as the Ameoba moves or feeds.
