1. Swazi Nontobeko
Mhlongo
Grade 10

2. Cell unit structure of life
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3. What is Biology?
Biology is the study of all
living things
 Living things are called
organisms
Organisms include bacteria,
protists, fungi, plants, &
animals
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4. All Living Things Share
Common Characteristics
1. Basic Unit is the Cell
2. They Reproduce
3. All Based On Universal
Genetic Code (DNA)
4. Grow & Develop
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5. Characteristics of
Organisms
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6. All Organisms are made
of Cells
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7. Facts About Cells
Cells are the smallest living
unit of an organism
All cells contain living
material called cytoplasm
All cells are surrounded by
a cell membrane that
controls what enters &
leaves the cell
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8. More Cell Facts
 More complex cells are called Eukaryotes
 These cells DO have a nucleus and
membrane-bound organelles
 Plants, animals, protists, & fungi are
examples
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9. Number of Cells
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Organisms may be:
• Unicellular –
composed of one cell
• Multicellular-
composed of many
cells that may
organize

10. Types of CellsTypes of Cells
Prokaryotes - Bacteria
Eukaryotes – Animals, plants, fungi, and
protists.
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Eukaryotic CellProkaryotic Cell

11. Prokaryotes
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Nucleoid region
contains the DNA
•Cell membrane &
cell wall
• Contain ribosomes
(no membrane) to
make proteins in
their cytoplasm

12. Two Types of
Reproduction
 Sexual
Reproduct
ion
 Involves 2 parents
 Egg fertilized by
sperm to make a
ZYGOTE
 Offspring
DIFFERENT from
parents
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13. Cells Have a Genetic Code
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14. Genetic Code
DNA (deoxyribose nucleic acid)
carries the genetic code for all
organisms
All organisms contain DNA
DNA codes for the proteins that
make up cells & do all the work
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15. Cells Require Food & Energy
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16. Food Requirements
Autotrophs can make
their own food
Photoautotrophs use
sunlight to make food
(photosynthesis)
Chemoautotrophs use
chemicals such as iron
& sulfur as their
energy
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17. Food Requirements
Heterotrophs can NOT make
their own food
They must consume other
organisms
Herbivores eat plants
Carnivores eat meat
Omnivores eat plants &
animals
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18. Basic Structure of a Cell
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19. Eukaryotic Cell
Contain 3 basic cell
structures:
Nucleus
Cell Membrane
Cytoplasm with
organelles
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20. Golgi Bodies
 Stacks ofStacks of flattenedflattened
sacssacs
 Have a shipping side &Have a shipping side &
a receiving sidea receiving side
 Receive &Receive & modifymodify
proteinsproteins made by ERmade by ER
 Transport vesiclesTransport vesicles
with modified proteinswith modified proteins
pinch off the endspinch off the ends
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Transport
vesicle

21. Lysosome
 Contain digestiveContain digestive
enzymesenzymes
 Break down food andBreak down food and
worn out cell parts forworn out cell parts for
cellscells
 Programmed for cellProgrammed for cell
death (lyse & releasedeath (lyse & release
enzymes to break downenzymes to break down
& recycle cell parts)& recycle cell parts)
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22. Nucleolus
 Cell may haveCell may have 1 to 31 to 3
nucleolinucleoli
 Inside nucleusInside nucleus
 Disappears when cellDisappears when cell
dividesdivides
 Makes ribosomesMakes ribosomes thatthat
make proteinsmake proteins
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23. Smooth & Rough Endoplasmic Reticulum
copyright cmassengale 23
Smooth ER lacks
ribosomes &
makes proteins
USED In the cell
Rough ER has
ribosomes on its
surface & makes
proteins to
EXPORt

24. In Animal Cells:In Animal Cells:
copyright cmassengale 24
Active cells like
muscles have more
mitochondria
Burn sugars to
produce energy ATP
Mitochondria

25. Cell or Plasma MembraneCell or Plasma Membrane
copyright cmassengale 25
Living layer
Controls the movement of
materials into and out of
the cell
Selectively permeable
Cell membrane

26. Cell WallCell Wall
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Nonliving layer
Gives structure and
shape to plant and
bacterial cells
Cell wall

27. Cytoplasm of a CellCytoplasm of a Cell
copyright cmassengale 27
Jelly-like substance
enclosed by cell
membrane
Provides a medium for
chemical reactions to
take place
Cytoplasm

28. Control Organelle
copyright cmassengale 28
Controls the normal
activities of the cell
Contain the DNA
Bounded by a
nuclear membrane
Contains chromosomes
Nucleus

29. Plant CellPlant Cell
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Dead layer
Large empty spaces
present between
cellulose fibers
Freely permeable
Cell wall

30. Plant CellPlant Cell
copyright cmassengale 30
Protect and support
the enclosed
substances
(protoplasm)
Resist entry of excess
water into the cell
Give shape to the cell
Cell wall

31. Plant Cell OrganellesPlant Cell Organelles
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Have a large central
vacuole
Surrounded by tonoplast
Contains cell sap
Sugars, proteins,
minerals, wastes, &
pigments
Vacuole

32. Animal cellAnimal cell
copyright cmassengale 32
mitochondrion
nucleus
glycogen
granule
cell
membrane
cytoplasm
No cell wall or
chloroplast
Stores glycogen
in the cytoplasm
for food energy
vacuole

33. Animal Cell Organelles
 Near the nucleus
 Paired structures
 Help cell divide
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34. There are different kinds ofThere are different kinds of
plant cellsplant cells
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Onion Epidermal Cells
Root Hair Cell
root hair
Guard Cells

35. Levels of OrganizationLevels of Organization
CELLS (muscle cells,nerve cells)
TISSUES (muscle, epithelium)
ORGANS (heart, lungs,
stomach)
SYSTEMS (circulatory system)
ORGANISM (human)
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36. There are different kinds of “animal”There are different kinds of “animal”
cellscells
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white blood cell
red blood cell
cheek cells
sperm
nerve cell
muscle cell
Amoeba
Paramecium

37. TissueTissue
A group of similar cells to
perform a particular function
Animals : epithelial tissue,
muscular tissue, nervous
tissue, and connective tissue
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38. Similarities between plant cells andSimilarities between plant cells and
animal cellsanimal cells
Both have a cell membrane,
ribosomes, cytoplasm, and DNA
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Both share many organelles,
including mitochondria

39. More Differences between Plant CellsMore Differences between Plant Cells
and Animal Cellsand Animal Cells
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Animal cells Plant cells
Vacuoles small or
absent
Glycogen as food
storage
Nucleus at the
center
Large central
vacuole
Starch as food
storage
Nucleus near cell
wall

40. The Structures of a Leaf (Plant
Organ)
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Stoma
Air Space
Spongy Mesophyll
Cell
Chloroplast
Palisade Mesophyll
Cell

41. The Structures of a Heart (Animal Organ)
copyright cmassengale 41

42. OrganOrgan
Different tissues group together
to carry out specialized functions
Heart : consists of muscles,
nervous tissue and blood
vessels
Leaf : consists of epidermis,
mesophyll and vascular tissue
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43. References
 This presentation is a mashup of 3 different sources. They are:
 Nardella .M.(2010) Cell structure
http://www.slideshare.net/mnardell103/cell-structure-5702506
Accessed 05 March 2014
 Mcnewbold. S. (2012) Cell structure
http://www.slideshare.net/mcnewbold/cell-structure-11143207
Accessed 05 March 2014
 Tas11244 .v. (2011) Characteristics of lifeii
http://www.slideshare.net/tas11244/characteristics-of-life-ii
Accessed 05 March 2014
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