Cell Biology BiologyCell Biology Biology

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Ce l l ce l l b i o lo g y Fa r mas iCe l l ce l l b i o lo g y Fa r mas i

Ce l l ce l l b i o lo g y Fa r mas i

Cell Biology Biology

The key to every biological problem must

Why Study Cell Biology?

finally be sought in the cell, for every living organism is, or at some time has been, a cell. E.B. Wilson, 1925

Some Random Cell Facts

The average human being is composed of around 100 Trillion composed of around 100 Trillion individual cells

WOW!!!

Properties of Life

Living organisms:– are composed of cells– are complex and ordered–– respond to their environment– can grow and reproduce– obtain and use energy– maintain internal balance– allow for evolutionary adaptation

The Cell Theory Complete

The 3 Basic Components of the Cell Theory were nowcomplete :

1. All organisms are composed of one or more cells. 1. All organisms are composed of one or more cells. (Schleiden & Schwann)(1838-39)

2. The cell is the basic unit of life in all living things. (Schleiden& Schwann)(1838-39)

3. All cells are produced by the division of preexisting cells. (Virchow)(1858)

Figure 14-37 Molecular Biology of the Cell (© Garland Science 2008)

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Modern Cell Theory

Modern Cell Theory contains 4 statements, in addition to the original Cell Theory :

1. The cell contains hereditary information(DNA) which is passed on from cell to cell during cell division.passed on from cell to cell during cell division.

2. All cells are basically the same in chemical composition and metabolic activities.

3. All basic chemical & physiological functions are carried out inside the cells.(movement, digestion,etc)

4. Cell activity depends on the activities of sub-cellular structures within the cell(organelles, nucleus, plasma membrane)

Figure 14-37 Molecular Biology of the Cell (© Garland Science 2008)

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What jobs do cells have to do?make proteins

proteins control everycell functioncell function

make energyfor daily lifefor growth

make more cellsgrowthrepair

renewalT E A C H I N G T E A M

Levels of Organization

Cellular Organizationcells

organellesmoleculesmolecules

atoms

The cell is the basic unit of life. T E A C H I N G T E A M

Levels of Organization

Organismal Levelorganism

organ systemsorgan systems

organs

tissues

SEL PROKARIOT DAN SEL EUKARIOT

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Types of Cells

Cell Types

Plant Cells Animal Cells

Eukaryotic Cells Prokaryotic Cells

http://www-class.unl.edu/bios201a/spring97/group6

Types of cellsTypes of cellsno organelles

Eukaryoteanimal cellsEukaryoteanimal cells

organelles

Eukaryoteplant cellsEukaryoteplant cells

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Plant Cell

Animal Cell

Animal and Plant Cells Have More Similarities Than Differences

Comparison of Procaryotic and Eucaryotic Organisms

Procaryotes Eucaryotes

Organisms archaea, bacteria protists, fungi, plants, animals

Cell linear dim. 1-10 ����m 10-100 ����m

Metabolism anaerobic or aerobic aerobic or anaerobic

Organelles nonucleus, chloroplasts, mitochondria, endoplasmic reticulum, etc.

DNA circular, in cytoplasm very long linear moleculesDNA circular, in cytoplasm very long linear moleculesbounded by nuclear envelope

RNA and protein RNA and protein synthesizedin same compartment

RNA synthesized in nucleus;protein, in cytoplasm

Cytoplasm no cytoskeleton: no cytoplasmic streaming, no endocytosis, no exocytosis

cytoskeleton composed of protein filaments; cytoplasmic streaming; endocytosis and exocytosis

Cell division chromosomes pulled apart byattachment to plasma membrane

chromosomes pulled apart bycytoskeletal spindle apparatus

Cellular organization

mainly unicellular mainly multicellular, with differentiation of many cell types

Feature Prokaryote Eukaryote

SizeSmall about 0.5 micrometers Up to 40 micrometers

Genetic material

Circular DNA (in cytoplasm)DNA in form of linear chromosomes ( in nucleus )

Organelles Few present, none membrane bound

Many organelles:•Double membranes e.g.: nucleus, mitochondria & chloroplastschloroplasts•Single membrane e.g.: GA, ER & lysosomes

Cell wallsRigid formed from glycoproteins (mainly murein)

•Fungi: rigid, formed from polysaccharide, chitin. •Plant: rigid, formed from polysaccharides. E.g.: cellulose. •Animals no cell wall

Ribosome’s 70s 80s

Cell Size

Cell Structure and Function

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Prokaryotic Cell

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Prokaryotic Cell

Prokaryotic Cell

Prokaryotic Cells� First cell type on earth� Cell type of Bacteria and Archaea

Prokaryotic Cells� No membrane bound nucleus� Nucleoid = region of DNA concentration� Organelles not bound by membranes

Struktur :

DNA & RNA : nukleoidTidak memiliki endomembran, mitokondria dan

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Tidak memiliki endomembran, mitokondria dankloroplas, tetapi punya struktur yang berfungsisama yaitu mesosom dan kromatoforContoh: bakteri dan ganggang biru.

Dinding Sel :

1. Struktur : tersusun atas: polisakarida, lemak, protein.Fungsi : sebagai pelindung, pemberi bentuk tetap dan

terdapat pori-pori sebagai media transport2. Membran plasma:

Struktur: tersusun atas molekul lemak dan protein.Fungsi: sebagaipelindungthdplingkungansekitar, Transport

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Fungsi: sebagaipelindungthdplingkungansekitar, Transport

3. Sitoplasma:Struktur: tersusun atas air, protein, lemak, mineral, dan enzim2.Fungsi: Enzim2, digunkan untuk mencerna makananekstraseluler dan melakukan metabolisme sel.

4. Mesosom :Struktur: terdapat pada membran plasma yang melekuk kedalam membentuk organel sel : mesosom.Fungsi: Sebagai penghasil energiTerdapat enzim: reaksi oksidasi untuk menghasilkan energi.

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5. Ribosom: tempat berlangsungnya sintesis protein.

6. DNA (Asam deoksiribonukleat) : deoxyribonucleic acid.Struktur: merupakan persenyawaan atas gula deoksiribosa, fosfat dan basa2 Nitrogen.Fungsi: sebagai pembawa informasi genetik

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7. RNA (Asam ribonukleat) : ribonucleic acid.Hasil transkripsi (hasil cetakan, hasil kopian) DNA. Membawa kode2 genetik sesuai dengan pesanan DNA

• Dinding sel pada sel prokariotik (bakteri) tersusun ataspeptidoglikan, yang berfungsi sebagai pelindung sel darilingkungan luar dan juga mencegah sel pecah (sitolisis)akibat tekanan osmotik melawan lingkungan yanghipotonik.

• Kromosompadaselprokariotikberbentuksirkular• Kromosompadaselprokariotikberbentuksirkular

• Sel prokariotik memiliki DNA extrachromosomal yangdisebut PLASMID, yang berfungsi sebagai daya tahanterhadap antibiotik.

Prokaryote Characteristics (review)

� Cell wall

� Why does a cell wall benefit a free-living organism?

� Gram Positive: Thick PG layer / no outer layer

� Gram Negative: Multi -layered & complex cell wall. � Gram Negative: Multi -layered & complex cell wall. Thin PG layer surrounded by a lipopolysaccharidemembrane.

**Penicillin inhibits the development of peptidoglycan. Which bacterial type is more affected by penicillin?

** Tears, mucous, and saliva contain ______ that dissolve bacterial cell walls away.

Prokaryote Characteristics (review)

� Capsule: Some bacteria develop a jelly-like coating surrounding the cell wall.

� Four functions:� Four functions:� Prevents the cell from drying out

� Helps the cells to stick to surfaces

� Helps prokaryotes to slide on surfaces

� Keep bacteria form being destroyed by host organism

Prokaryote Characteristics (review)

� Flagella� Used for motility

� Spin like propellers

� Structurally different than eukaryotic flagellaStructurally different than eukaryotic flagella

� What is the difference?

� Pili� Short, bristle appendages with two functions

• Attach bacteria to surfaces

• Assist in transfer of DNA during conjugation

Eukaryotic Cells

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