CELLs
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CELLs. By. Sangarun sangarchat [email protected]. This mean of cells:. The cell is one of the most basic units of life There are millions of different types of cells . There are cells that are organisms onto themselves, such as microscopic amoeba and bacteria cells. - PowerPoint PPT Presentation
Transcript of CELLs
This mean of cells:
The cell is one of the most basic units of life There are millions of different types of cells. There are cells that are organisms onto themselves, such as microscopic amoeba and bacteria cells.
There are two types of cells: eukaryotic and prokaryotic. Prokaryotic cells are usually independent, while eukaryotic cells are often found in multicellular organisms.
Anatomy of cells
And there are cells that only function when part of a larger organism, such as the cells that make up your body. The cell is the smallest unit of life in our bodies. In the body, there are brain cells, skin cells, liver cells, stomach cells, and the list goes on. All of these cells have unique functions and features.
Procaryotic: These cells are simple in structure, with no recognizable organelles. They have an outer cell wall that gives them shape. Just under the rigid cell wall is the more fluid cell membrane. The cytoplasm enclosed within the cell membrane does not exhibit much structure when viewed by electron microscopy
Procaryotic
Eucaryotic: The cells of protozoa, higher plants and animals are highly structured. These cells tend to be larger than the cells of bacteria, and have developed specialized packaging and transport mechanisms that may be necessary to support their larger size.
Eukaryotic
Eukaryotic Cell
Prokaryotes Eukaryotes Typical organism bacteria, archaea protists , fungi,
plants, animals Typical size ~ 1–10 µm ~ 10–100 µm (
sperm cells, apart from the tail, are smaller)
Type of nucleus Type of nucleus nucleoid region; no real nucleusreal nucleus with double membrane
Table 1: Comparison of features of prokaryotic and eukaryotic cells
DNA circular (usually) linear molecules (chromosomes) with histone proteins
linear molecules (chromosomes) with histone proteins
coupled in cytoplasm
RNA-synthesis inside the nucleusprotein synthesis in cytoplasm
Ribosomes 0S+30S60 5S+40S
unicellular
amoeba euglena
parameciun
amoebaAmoeba Free-living protozoan groups that inhabit soils and natural waters are extremely diverse, not only in their structure but also in the manner in which they feed, reproduce, and move.
Euglena is a genus of unicellular protists. Currently, over 1,000 species of Euglena have been described. There are many to be discovered. Marin et al. (2003) revised the genus to include several species without chloroplasts. It can photosynthesis.
Euglena
Cyanobacteria as blue-green algaeis phylum of bacter are aquatic and photosynthetic, that is, they live in the water, and can manufacture their own food. Because they are bacteria, they are quite small and usually unicellular,
Cyanobacteria
blue-green algae
though they often grow in colonies large enough to see. They have the distinction of being the oldest known fossils, more than 3.5 billion years old, in fact! It may surprise you then to know that the cyanobacteria are still around; they are one of the largest and most important groups of bacteria on earth.
Paramecium is a group of unicellular ciliate protozoa, which are commonly studied as a representative of the ciliate group, and range from about 50 to 350 μm in length. Simple cilia cover the body, which allow the cell to move with a synchronous motion.
Paramecium
Animal Cell Structure
Cell Structure
Unit Membrane Typical Structure - composed of protein and lipid (fat) molecules
Structure - same as unit membrane. Function - acts as a boundary layer to contain the cytoplasm (fluid in cell) - interlocking surfaces bind cells together
Cell Membrane
- selectively permeable to select chemicals that pass in and out of cells
Cell Wall Structure - a non-living secretion of the cell membrane, composed of cellulose - cellulose fibrils deposited in alternating layers for strength - contains pits (openings) that make it totally permeable
Cell Wall
Function of cell wall - provides protection from physical injury
Chloroplast Structure - composed of a double layer of modified membrane (protein, chlorophyll, lipid) - inner membrane invaginates to form layers called "grana" (sing., granum) where chlorophyll is concentrated
Chloroplast
Centriole Structure - nine triplets of microtubules form one centriole - two centrioles form one centrosome Function
- forms spindle fibres to separate chromosomes during cell division
Centriole
Vacuole Structure - a single layer of unit membrane enclosing fluid in a sack Function - produces turgor pressure against cell wall for support - stores water and various chemicals - may store insoluble wastes
Vacuole
Endoplasmic Reticulum (ER) Structure
- sheets of unit membrane with ribosomes on the outside - forms a tubular network throughout the cell
Endoplasmic Reticulum (ER)
Function
- transports chemicals between cells and within cells - provides a large surface area for the organization of chemical reactions and synthesis
Some Endoplasmic Reticulum have not
Ribosome on the outside. It’s function are synthesis steroid and detoxification of poisons
Endoplasmic Reticulum (ER)
Ribosome Structure - non-membraneous, spherical bodies composed of RNA (ribonucleic acid) and protein enzymes
Function - site of protein synthesis
Ribosome
Golgi Apparatus Structure - stacks of flattened sacs of unit membrane (cisternae) - vesicles pinch off the dges Function - modifies chemicals to make them functional - packaging chemicals in Vesicles for send out off cell.
Golgi Apparatus
Mitochondrion Structure - composed of modified double unit membrane (protein, lipid) - inner membrane infolded to form cristae Function - site of cellular respiration ie. the release of chemical energy from food
Mitochondrion
Glucose+Oxygen ---> Carbondioxide + Water + Energy
Lysosome Structure - membrane bound bag containing hydrolytic enzymes - hydrolytic enzyme = (water split biological catalyst) i.e. using water to split chemical bonds
Lysosome
Function
- break large molecules into small molecules by inserting a molecule of water into the chemical bond
Lysosome
nuclear envelope nucleolus chromatin nucleoplasm
Nucleus
Nuclear Envelope Structure - two unit membranes with a fluid-filled space - nuclear pores present - outer membrane may be continuous with endoplasmic reticulum
Nucleus
Function - selectively permeable to control movement in or out - contains nuclear contents
Nuclear Envelope
Chromatin Structure - composed of long thin strands of DNA Function
- contains instructions that control cell metabolism and heredity
Chromatin
Nucleolus Structure
- non - membraneous matrix of RNA (ribonucleic acid) and protein Function - works with ribosomes in the synthesis of protein
Nucleolus
- Usually in the form of chromatin
- Contains genetic information
- Composed of DNA
- Thicken for cellular division
- Set number per species (i.e. 23 pairs for human)
Chromosomes
1. Are euglena unicellular or multicellular?
2. What Kingdom do euglena belong to? What Phylum?
3. What organelle carries out photosynthesis?
4. On which end is the flagellum located?
5. Define autotrophic.
Write answers to the following: in notebook
6. Define heterotrophic.
7. Describe the two ways in which the euglena get their nutrients.
8. What is the eyespot used for?
9. What is the function of the nucleus?
10. What is the function of the contractile vacuole? What would happen if the cell did not have this organelle.
Cell Structure
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Cell Structure
11. This structure is made of DNA
12. Produces ATP
13. Creates turgor pressure
14. New proteins are made on the
15. This organelle controls entry into the cell
Write answers to the following:
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