Page 16 - Biology_F5

Cytology

(g) Observe the specimen under the light permeable to substances and controls the
microscope at low, medium, and high exchange of materials between the cell
power objective lenses. The images tend and its environment. Beneath the cell
to be smaller under low power objective surface membrane, there is a protoplasm
lens. However, if more magnification which is made up of cytoplasm and the
is needed, change objective lenses to nucleus (Figure 1.5). Like in the plant
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medium and high power. Structures such cell, the cytoplasm of the animal cell
as nucleus, cytoplasm, chloroplasts, is jelly-like fluid filling the cell and it
vacuole, cell wall, and cell membrane houses all cell organelles. The cytosol
can be clearly seen. or cytoplasmic matrix is a fluid found in
the cell organelles, such as mitochondria
Question and ribosomes. The cytosol is a site for
1. Draw what you have observed and metabolic activities in the cell organelles.
compare your diagram with that of Mitochondria are called the powerhouses
Figure 1.4. of the cell because they produce energy in

2. Describe the structure of the the form of Adenosine Triphosphate (ATP)
observed part. through the process of respiration. The
produced energy is used to run metabolic
activities of the cell. The nucleus is the
Safety precaution central part, containing the hereditary
Be careful when working with sharp (genetic) material. It also controls cell
objects such as needle, knife or activities such as growth, cell division,
surgical blade. DNA replication, and protein synthesis.

The animal cell Ribosomes are the smallest organelles
Animal cells are eukaryotic cells with responsible for protein synthesis in the
a membrane bound nucleus. Unlike the cell. Some ribosomes are located on the
eukaryotic cells of plants and fungi, animal surface of the endoplasmic reticulum which
cells do not have a cell wall. Animal cell is a large folded membrane system in the
comprises different cell organelles and cell cytoplasm. Like plant cell, animal cell has
structures which perform specific functions rough endoplasmic reticulum and smooth
necessary for the cell. The cell organelles endoplasmic reticulum. Moreover, the animal
have a vast range of functions. The animal cell has small vesicles in the cytoplasm known
cells contains centrioles, endoplasmic as Golgi vesicles which are responsible for
reticulum, Golgi apparatus, lysosomes, the storage of enzymes and formation of
microfilaments, microtubules, mitochondria, lysosomes. Lysosomes are small structures in
nucleus, peroxisomes, plasma membrane, the cytoplasm which contain digestive juices
ribosomes, cilia, and flagella. responsible for breaking down of old cell
parts. There are also long structures called
Structure of the animal cell microtubules or microfilaments. These are
The outer boundary of the animal cell responsible for all cell movements, and they
is a cell membrane; which is selectively provide the cell with cytoskeletal support.

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