Eukaryotes vs Prokaryotes

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FEATURES EUKARYOTIC CELLS PROKARYOTIC  CELLS
Nucleus:      Present Absent
Number of chromosomes:      More than one One–but not true chromosome:Plasmids
Cell Type:   Multicellular Unicellular
True Membrane bound Nucleus: Present Absent
Example: Animals and Plants Bacteria and Archaea
Telomeres: Present (Linear DNA) Circular DNA doesn’t need telemeres
Genetic Recombination: Mitosis and fusion of gametes Partial, undirectional transfers DNA
Lysosomes and peroxisomes: Present Absent
Microtubules: Present Absent or rare
Endoplasmic reticulum: Present Absent
Mitochondria: Present Absent
Cytoskeleton: Present May be absent
DNA wrapping on proteins: Yes No
Ribosomes: larger smaller
Vesicles: Present Present
Golgi apparatus: Present Absent
Mitosis: Yes No—but has binary fission
Chloroplasts: Present (in plants) Absent; chlorophyll scattered in the cytoplasm
Flagella: Microscopic in size; membranebound; usually arranged as nine doublets surrounding two singlets Submicroscopic in size, composed of only one fiber
Permeability of Nuclear Membrane: Selective not present
Plasma membrane with steriod: Yes Usually no
Cell wall: Only in plant cells (chemically simpler) Usually chemically complexed
Vacuoles: Present Present
Cell size: 10-100um 1-10um

Animals Cells vs Plant Cells

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Some of the differences between animal and plant cell

ANIMAL CELLS PLANT CELLS
Does not have a cell wall,  irregular in shape Has a cell wall, regular in shape
No chloroplast present Chloroplast present
Small temporary vacuoles or no vacuole Large vacuoles located in the centre of the cell
Starch grains not present Starch grains present
The nucleus is usually located centrally Due to the central location of the vacuole, the nucleus of the cell may be located at the edge of the cell

Similarities between plant and animal cells:

-Both have a cell surface membrane that surrounds the cell.

-Both contain endoplasmic reticulum

-Both have cytoplasm

-Both contain ribosomes

-Both contain a nucleus

-Both contain mitochondria

The History of the Cell Theory

Just btw this youtube video  has a really fun and easy understanding of the cell theory

watch it .. you are guaranteed to like and understand the cell theory

p.s its a bit funny too! 🙂 happy watching

In our first lecture for biochemistry we again familiarized ourselves with cell biology.
Did you know that Robert Hooke discovered the CELL?

Well, he did, way back in 1665, he decided to look at a shard of cork and sighted ‘cells’. His initial thoughts were that they belong to plants only.

Then …

In 1838, Matthias Schleiden and Theodor Schwann introduced a unified theory of botany and zoology. Schlieden investigated plants microscopically and conceived that plants were made up of recongnizable units, or cells. While Schawan extended the theory to animals.

The cell theory states that:
1. All life forms are made from one or more cells.
2. Cells only arise from pre-existing cells.
3. The cell is the smallest form of life.

Rudolf Virchow, just happen to be the guy that united the CELL THEORY that cells arise from pre-existing cells.

TEST YOUR KNOWLEDGE – THE CELL QUIZ

1. What part of the cell is responsible for breaking down and digesting things?

(a)  ribosomes

(b) lysosomes

(c)  endoplasmic reticulum

(d) vacuole

2. What part of the cell serves as the intracellular highway?

(a)   endoplasmic reticulum

(b)  golgi apparatus

(c)   cell membrane

(d)  Mitochondria

3. Which of the following would you NOT find in a bacterial cell?

(a)   DNA

(b)  cell membrane

(c)   golgi apparatus

(d)  Ribosomes

4. Which of the following is found in plant cells, but not animal cells?

(a)   cell wall

(b)  vacuole

(c)   mitochondria

(d)  endoplasmic reticulum

5. The jellylike interior of the cell is called the:

(a)   vacuole

(b)  cytoplasm

(c)   cytoskeleton

(d)  nucleus

6. What part of the cell makes proteins?

(a)   ribosomes

(b)  mitochondria

(c)   lysosomes

(d)  vacuole

7. Where are ribosomes usually located in animal and plant cells?

(a)   inside the nucleus

(b)  near the cell membrane

(c)   on the endoplasmic reticulum

(d)  inside the vacuole

8. What part of the cell serves to process, package and export proteins?

(a)   mitochondria

(b)  endoplasmic reticulum

(c)   nucleolus

(d)  golgi apparatus

9. Who was the first person to see cells under the microscope and give them a name?

(a)  Anton van Leeuwenhoek

(b) Robert Hooke

(c)  Theodor Schwann

(d) Matthias Schleiden

10. He discovered that all plants were made of cells, which contributed to the development of the cell theory:

(a)  Anton van Leeuwenhoek

(b) Robert Hooke

(c)  Theodor Schwann

(d) Matthias Schleiden

11. He advanced the cell theory with his conclusion that cells could only come from other cells:

(a)  Anton van Leeuwenhoek

(b) Rudolph Virchow

(c)  Theodor Schwann

(d) Robert Hooke

12. This structure serves as the outer boundary of the eukaryotic cell:

(a)  flagella

(b) cytoskeleton

(c)  cell membrane

(d) capsule

13. Unlike eukaryotes, prokaryotes do not have:

(a)  DNA

(b) cytoplasm

(c)  cell walls

(d) a membrane bound nucleus

14. The cell theory states….

1. All life forms are made from one or more cells.

2. Cells only arise from pre-existing cells.

3. The cell is the smallest form of life

4. cells must contain DNA

(A) 1 only

(B) 2, 4

(C) 1, 2, 3

(D) 3, 4

(E) All of the above

15. The word cyto means:

(a)  cell

(b) dark

(c)  jelly

(d) small

16. Tiny structures that carry out cell functions are collectively called:

(a)  animalcules

(b) organelles

(c)  tissues

(d) ribosomes

17. Which of the following organelles is most important in providing energy to the cell?

(a)   mitochondrion

(b)  centrosome

(c)   nucleus

(d)  peroxisome

18. Name the membrane valves that open and close for potassium efflux and sodium influx.

(a)  ion channels

(b) vacuoles

(c)  capillaries

(d) cytokines

19. What organelle in higher plant cells contains chlorophyll?

(a)   chloroplasts

(b)  cytosol

(c)   secretory vesicles

(d)  nucleus

20. What is the difference between cytosol and cytoplasm?

(a)   cytosol is the intra- cellular fluid, cytoplasm is part of the cell which contains the entire cell membrane

(b)  cytoplasm  is the intra- cellular fluid, cytosol is part of the cell which contains the entire cell membrane

(c)   metabolic reactions take place in the cytoplasm and not the cytosol

(d)  cytosol is made up of 60% water, cytoplasm is made up of 40% water only

(e)  answer not given