Cells and function: The Life's Building Blocks

1. Cells and
Functions: The
Life's Building
Blocks
By Keizar

2. Types of Cells
Eukaryotic Cells:
Definition: Eukaryotic cells
are complex, membrane-
bound structures that
constitute the cells of plants,
animals, fungi, and protists.
These cells are
characterized by a true
nucleus, which houses
genetic material in the form
of chromosomes. In addition
to the nucleus, eukaryotic
cells possess membrane-
bound organelles that carry
out specific functions,
contributing to the cell's
Prokaryotic Cells:
Definition: Prokaryotic cells
are simple, single-celled
organisms that lack a true
nucleus and membrane-
bound organelles. They are
found in bacteria and
archaea. In prokaryotes,
genetic material is present in
a region called the nucleoid,
which lacks a surrounding
membrane. Prokaryotic cells
are known for their small
size and streamlined
structure.

3. Eukaryotic
Cells
Key Features:
Nucleus: Eukaryotic cells have a well-defined nucleus that
contains the genetic material (DNA) organized into chromosomes.
Membrane-Bound Organelles: Eukaryotic cells contain various
membrane-bound organelles such as the endoplasmic reticulum,
Golgi apparatus, mitochondria, chloroplasts (in plant cells), and
others, each with specific roles in cellular functions.
Complex Structure: These cells exhibit a more complex and
compartmentalized structure compared to prokaryotic cells,
allowing for specialization of functions within the cell.
Cellular Division: Eukaryotic cells undergo mitosis during cell
division, ensuring the faithful distribution of genetic material to
daughter cells.

4. Prokaryotic
Cells
Key Features:
Nucleoid: Prokaryotic cells have a nucleoid, which is a region
within the cell where genetic material, usually a single circular
DNA molecule, is located. However, it lacks a membrane.
No Membrane-Bound Organelles: Unlike eukaryotic cells,
prokaryotic cells do not have membrane-bound organelles.
Instead, they have specialized regions for particular functions.
Simpler Structure: Prokaryotic cells have a simpler overall
structure, with fewer internal compartments and a smaller size
compared to eukaryotic cells.
Binary Fission: Prokaryotic cells reproduce primarily through
binary fission, a process in which the cell divides into two
identical daughter cells.

5. Differences
Differences:
Nucleus: Eukaryotic cells have a true nucleus with a membrane.
Prokaryotic cells have a nucleoid, lacking a nuclear
membrane.
Organelles: Eukaryotic cells have membrane-bound organelles.
Prokaryotic cells lack membrane-bound organelles.
Size: Eukaryotic cells are generally larger.
Prokaryotic cells are smaller.
Cellular
Division:
Eukaryotic cells undergo mitosis.
Prokaryotic cells undergo binary fission.

6. Similarities
Similarities:
Cell Membrane: Both eukaryotic and prokaryotic
cells have a cell membrane that regulates the
passage of substances in and out of the cell.
Genetic Material: Both types of cells contain
genetic material (DNA) that carries instructions for
cellular functions.
Cytoplasm: Both cells have a cytoplasm, a gel-
like substance that houses various cellular
components.
Ribosomes: Ribosomes, essential for protein
synthesis, are present in both cell types.

8. Cells: The Essence of Life
• Description: Cells are the fundamental units of life, the microscopic building
blocks that form the basis of all living organisms. These tiny structures are like the
architects of life, carrying out a multitude of functions that collectively contribute to
the complexity and diversity of living organisms.

9. Cells: The Essence of Life
• Meaning: Imagine cells as the smallest, functional components that come together
to create the symphony of life. They are the microscopic powerhouses,
orchestrating various activities to ensure the survival and functionality of the
organism they belong to.

10. Cells: The Essence of Life
• Functions:
1. Structural Integrity: Cells provide the structural foundation for living organisms.
They come together to form tissues, organs, and systems, contributing to the
overall structure and integrity of the organism.
2. Metabolism and Energy Production: Cells are the metabolic engines of life. They
carry out chemical processes that break down nutrients to release energy,
essential for the organism's various activities.
3. Genetic Information: The cell nucleus houses genetic material, DNA, which
carries the instructions for the organism's development, growth, and functioning.
This information is passed on from generation to generation.
4. Reproduction: Cells are responsible for the reproduction and growth of
organisms. Through processes like cell division, they ensure the continuity of life.
5. Communication: Cells communicate with each other through complex signaling
pathways. This communication is crucial for coordinating activities and responding
to changes in the organism's internal and external environment.
6. Homeostasis: Cells play a vital role in maintaining the internal balance of the
organism, known as homeostasis. They regulate factors like temperature, pH, and
nutrient levels to ensure optimal conditions for life.

11. Cells: The
Essence of
Life
Structures:
Cell Membrane: The outer boundary of the cell, regulating the
passage of substances in and out.
Cytoplasm: The gel-like substance within the cell that houses
organelles and supports cellular activities.
Nucleus: The control center containing genetic material (DNA) that
governs cellular functions and inheritance.
Mitochondria: Powerhouses of the cell, responsible for energy
production through cellular respiration.
Endoplasmic Reticulum (ER): A network of membranes involved in
the synthesis and transport of proteins and lipids.
Golgi Apparatus: Modifies, packages, and transports proteins for
secretion or for use within the cell.
Ribosomes: Cellular structures where proteins are synthesized.
Vacuoles (in plant cells): Storage compartments for nutrients,
waste products, and cellular materials.
Lysosomes: Contain enzymes for breaking down cellular waste and
foreign substances.
Cytoskeleton: Provides structural support and facilitates cell
movement.

12. Cell
• A cell is a mass of cytoplasm that is bound externally by a cell membrane. Usually microscopic in
size, cells are the smallest structural units of living matter and compose all living things. Most cells
have one or more nuclei and other organelles that carry out a variety of tasks.
• Cells are the basic structures of all living organisms. Cells provide structure for the body, take in
nutrients from food and carry out important functions. Cells group together to form tissues, which in
turn group together to form organs, such as the heart and brain.

13. Summary
• The basic unit of life.
• The smallest, functional component of living organisms.
• Carries out essential functions for the organism's survival.
• Eukaryotic Cells:
• Found in plants, animals, fungi, and protists.
• Has a true nucleus with a membrane.
• Contains membrane-bound organelles like the endoplasmic reticulum, Golgi apparatus, and
mitochondria.
• Larger and more complex compared to prokaryotic cells.
• Undergoes mitosis during cellular division.
• Prokaryotic Cells:
• Found in bacteria and archaea.
• Lacks a true nucleus; genetic material is in the nucleoid.
• Lacks membrane-bound organelles.
• Smaller and simpler in structure.
• Reproduces primarily through binary fission.

14. Summary
• Cell Structures:
1. Cell Membrane:
1. Regulates the passage of substances in and out of the cell.
2. Nucleus (Eukaryotic Cells):
1. Contains genetic material (DNA) in chromosomes.
3. Nucleoid (Prokaryotic Cells):
1. Region where genetic material is located; lacks a nuclear membrane.
4. Membrane-Bound Organelles (Eukaryotic Cells):
1. Endoplasmic reticulum, Golgi apparatus, mitochondria, etc.
5. Ribosomes:
1. Sites for protein synthesis, present in both cell types.
6. Cytoplasm:
1. Gel-like substance that houses cellular components.
7. Mitochondria (Eukaryotic Cells):
1. Powerhouses of the cell; involved in energy production.

15. Summary
• Cell Functions:
1. Structural Integrity:
1. Forms tissues, organs, and systems in multicellular organisms.
2. Metabolism and Energy Production:
1. Breaks down nutrients to release energy.
3. Genetic Information:
1. Houses and passes on genetic instructions for development and functioning.
4. Reproduction:
1. Ensures the continuity of life through cell division.
5. Communication:
1. Cells communicate to coordinate activities and respond to the environment.
6. Homeostasis:
1. Maintains internal balance in the organism.
• Understanding the distinctions and functions of cells provides a foundation for
exploring the complexities of life and the diverse ways in which living organisms
are structured and function.

16. Quiz Time!

17. And That’s All Thank You
•Cells are the basic of life, they are important
in our body because they are the cause why
we are exists