This document summarizes the levels of organization in the human body from molecules to tissues. It begins with the basic biomolecules that make up cells, including proteins, carbohydrates, lipids, nucleic acids, and water. It then describes the structures and organelles found in eukaryotic animal and plant cells, including the cell membrane, nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes, cytoskeleton, centrosome, ribosomes, vacuoles, and chloroplasts (plant cells only). It also briefly discusses prokaryotic cells. Finally, it reviews the four main tissue types - epithelial, connective, muscle and nervous tissue - and some examples of each type

1. Unit 1:
Levels of Organization of
the Human Body

3. The Molecules of Life (Biomolecules):
WATER
Inorganic: (common to non-living and
living matter)
MINERALS
CARBOHYDRATES
LIPIDS (only in living matter
they all contain C)
PROTEINS
NUCLEIC ACIDS
Organic:

8. ANIMAL CELL

9. Eukaryotic Cell: Animal Cell

11. Cell Membrane
A phospholipid bilayer with
proteins.
Isolates the cell and controls the
substance exchange with the
medium.
Cytoplasm
Content of the cell:
Cytosol (liquid): water and soluble substances.
Cell Organelles

12. Nucleus
Controls the cell activity.
Double membrane, with pores.
Nucleoplasm.
Nucleolus (RNA+proteins): where
ribosomes are formed.
Chromatin (DNA+proteins)
transforms into chromosomes
when the cell is going to divide.

13. Mitochondria
Double membrane (outer and inner
The inner membrane forms cristae.
The inner space (matrix) contains
DNA and ribosomes!
They produce energy in a metabolic
process called cellular respiration.

15. Endoplasmic Reticulum
System of membranes that
extend over the cytoplasm.
Two types:
ROUGH ER: with ribosomes
attached. Produces, stores and
trasnports proteins
SMOOTH ER: no ribosomes.
Produces, stores and
transports lipids.

16. Golgi Apparatus (or Complex)
Composed of membranous flat sacs piled
up forming stacks.
It modifies the substances that receives
from the ER, and secrets them outside the
cell.
Lysosomes
Vesicles formed in the Golgi
Complex.
They contain digestive enzymes
that break down large
molecules or cell organelles.
If they broke, the cell would be
destroyed by them.

17. Vacuoles
Vesicles that store substances.
Plant cells usually have 1 or 2 big vacuoles.
Animal cells have many small vacuoles.

18. Ribosomes
Present in all types of cells (prokaryotic and eukaryotic)
Composed of RNA and proteins. Produced in the nucleolus.
Not membranous.
May be floating free in the cytoplasm or attached to the RER
They synthesize (=produce) proteins.

19. Cytoskeleton
Only present in animal cells.
Composed of protein filaments of two types:
Microfilaments
Microtubules
Functions:
Helps the cell to divide (mitosis)
Contraction
Cell movement (form pseudopodia)
Transport inside the cytoplasm.
Form the centriols, cillia and flagella.

20. Centrosome
Only present in animal cells.
Composed of two centrioles,
one perpendicular to the other.
It organizes the cytoskeleton
and helps the cell to divide
(mitotic spindle)

21. Prokaryotic cell
No nucleus
Circular DNA floating in the cytoplasm
No membranous organelles
Ribosomes
Mesosomes
Cell wall covering
the Cell Memebrane
Capsule
Flagellum

22. PLANT CELL

23. Chapter 5 9
Generalized Cell
Animal
Cell
Plant
Cell
Nucleus
Golgi
Mitochondria
Endoplasmic
Reticulum
Centrioles Chloroplasts

25. Eukaryotic Cell: Plant Cell

26. Chloroplasts
Only present in plant cells.
Like mitochondria, they have a double
membrane (outer and inner).
Like mitochondria, they have DNA and
ribosomes.
The inner membrane forms a system of
sacs piled up forming structures called
thylakoids. The stacks of thylakoids are
called grana.
The space inside the inner membrane is
called stroma.
They contain pigments like chlorophyll,
that make photosynthesis possible.

27. Cell Wall
Only present in plant cells.
It covers and protects the cell membrane.
It gives the cell a fixed shape.
Formed by a matrix of cellulose molecules.

28. HUMAN TISSUES

30. Simple Epithelial
Tissues
Pseudostratified
Epithelial Tissues
Stratified
Epithelial Tissues
EPITHELIAL TISSUES

31. Types of Epithelia

33. Simple ColumnarSimple Cuboidal
Simple
Squamous

34. Stratified Squamous Epithelium

35. Pseudostratified Columnar Epithelium

37. CONNECTIVE TISSUES

38. Cells (Fibroblasts) + Fibres + Extracellular matrix
Loose Connective Tissue

39. Cells (Adipocytes) + Extracellular Matrix
Adipose Tissue

40. Cells (Fibroblasts) + Fibres (collagen) + Extracellular matrix
Dense Connective Tissue

41. Cartilage Tissue
Cells: Chondrocytes
Extracellular Matrix
(elastic)

42. Bone Tissue
Cells (Osteocytes) + Extracellular Matrix (hard,
calcified)

43. Blood
Cells
Red Blood Cells
White Blood Cells
Platelets
+ Liquid Extracellular Matrix
(plasma)

44. MUSCLE TISSUE
STRIATED,
INVOLUNTARY
STRIATED,
VOLUNTARY
NO STIATIONS,
INVOLUNTARY

51. NERVOUS TISSUE

52. Neurons:

53. Neurons with a Glial Cell
(Astrocyte)