All living things are divided into three domains: Bacteria, Archaea, and Eukarya. Prokaryotes are single-celled organisms from the Bacteria and Archaea domains that have simpler cells without organelles. Eukaryotes include animals, plants, fungi and protists and have more complex cells with organelles like mitochondria and a nucleus. The main differences between prokaryotic and eukaryotic cells are that eukaryotes have a nucleus, larger and more complex ribosomes, and plant eukaryotes have a cell wall.

1. Lecture #02
Amjad Khan Afridi
Lecturer,
Department of Health &

2. All living things can be divided into three basic
domains:
⚫Bacteria
⚫Archaea and
⚫Eukarya.
Introduction

3. ⚫ The primarily single-celled organisms found in the Bacteria and
Archaea domains are known as prokaryotes.
⚫ These organisms are made of prokaryotic cells — the smallest,
simplest and most ancient cells.
Prokaryotes

6. Gram Positive and Gram Negative bacteria Cell wall difference

9. EUKARYOTES CELL

10. Eukaryotes
⚫ Organisms in the Eukarya domain are made of the more complex
eukaryotic cells.
⚫ These organisms, called eukaryotes, can be unicellular or
multicellular and include animals, plants, fungi and protists.
⚫ Many people are unclear on whether yeasts or fungi are prokaryotes
or eukaryotes.
⚫ Both are eukaryotes and share similar cell structure to all other
eukaryotes.

12. Difference in between Plant cell & Animal Cell

14. How do prokaryotes and eukaryotes differ?

15. Organelles in Eukaryotic Cells
⚫ Eukaryotic cells have several other membrane-bound organelles not
found in prokaryotic cells.
⚫ These include the mitochondria (convert food energy into
adenosine triphosphate, or ATP, to power biochemical reactions);
rough and smooth endoplasmic reticulum ,golgi complex and in
the case of plant cells, chloroplasts
⚫ All of these organelles are located in the eukaryotic cell's
cytoplasm.

16. Difference
⚫ The main differences between prokaryotic and eukaryotic cells are;
⚫ The presence of A nucleus,
⚫ The size and complexity of the ribosomes,
⚫ The presence of A cell wall.

17. Ribosomes
⚫ In eukaryotic cells, the ribosomes are bigger, more complex and
bound by a membrane. They can be found in various places:
Sometimes in the cytoplasm; on the endoplasmic reticulum; or
attached to the nuclear membrane (covering on the nucleus).
⚫ In prokaryotic cells, the ribosomes are scattered and floating freely
throughout the cytoplasm. The ribosomes in prokaryotic cells also have
smaller subunits. All ribosomes (in both eukaryotic and prokaryotic cells)
are made of two subunits — one larger and one smaller. In eukaryotes,
these pieces are identified by scientists as the 60-S and 40-S subunits. In
prokaryotes, the ribosomes are made of slightly smaller subunits, called
50-S and 30- S.

18. Cell Walls
⚫ Most prokaryotic cells have a rigid cell wall that surrounds the plasma
membrane and gives shape to the organism.
⚫ In eukaryotes, vertebrates don't have a cell wall but plants do. The
cell walls of prokaryotes differ chemically from the eukaryotic cell
walls of plant cells, which are primarily made of cellulose.
⚫ In bacteria, for example, the cell walls are composed of peptidoglycans
(sugars and amino acids),

20. 22nd March, 2022