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Zoology 145 course

Zoology 145 courseGeneral Animal

BiologyGeneral Animal BiologyFor Premedical For Premedical

StudentStudent

Course Instructor: Dr. Course Instructor: Dr. Ahmed AlhimaidiAhmed Alhimaidi

Course Instructor: Dr. Course Instructor: Dr. Ahmed AlhimaidiAhmed Alhimaidi22ndnd Semester 1430-1431H Semester 1430-1431H

Reference text book: Biology Reference text book: Biology By : Campbell and ReeceBy : Campbell and Reece

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Cell Theory Cell Theory Cell Theory Cell Theory

1- All organisms are composed of one or1- All organisms are composed of one or more of cells. more of cells.

2- Cell is the basic unit of life.2- Cell is the basic unit of life.

3- The new cell arises only from pre-3- The new cell arises only from pre- existing cell. existing cell.

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The CellThe CellThe CellThe CellThe Organism’s Basic Unit of Structure and FunctionThe Organism’s Basic Unit of Structure and Function

ProkaryoticProkaryoticProkaryoticProkaryotic EukaryoticEukaryoticEukaryoticEukaryoticTypesTypes

of cellsof cells

Micro-organisms All other forms of life cells

Cellulae (Small room)

بدائية

النواة

الحية الكائناتالدقيقة

حقيقة متقدمة أوالنواة

All cells are surrounded by a All cells are surrounded by a plasma membrane plasma membrane بالزمى بالزمى غشاء ..غشاء

The semi-fluid substance The semi-fluid substance سائلة النصف سائلة المادة النصف within the cell is called within the cell is called المادة

“cytosol”“cytosol”, , السيتوبالزمالسيتوبالزم containing the cell organelles containing the cell organelles الخلية الخلية ِع=ضيات ..ِع=ضيات

All cells contain chromosomes which have genes in the form of DNA.All cells contain chromosomes which have genes in the form of DNA.

All cells have tiny organelles All cells have tiny organelles صغيرة صغيرة ِعضيات called called ““Ribosomes”Ribosomes” that that ِعضيات

make proteins.make proteins.

1). 1). ProkaryoticProkaryotic and and eukaryoticeukaryotic cells cells differ in size and complexity differ in size and complexity

SimilaritiesSimilarities أوجه التشابهSimilaritiesSimilarities أوجه التشابه

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A major difference A major difference األساسى األساسى الفرق between prokaryotic and between prokaryotic and الفرق

eukaryotic cells is the eukaryotic cells is the location of chromosomeslocation of chromosomes موضع موضع

..الصبغياتالصبغيات In an eukaryotic cell: chromosomes are contained in a true In an eukaryotic cell: chromosomes are contained in a true nucleus nucleus ((النواةالنواة

))..

In a prokaryotic cell: the DNA is concentrated in the In a prokaryotic cell: the DNA is concentrated in the nucleoidnucleoid (( نواة نواة شـبه ( (شـبه

without a membrane (without a membrane ( غـشاء غـشاء بدون .separating it from the rest of the cell. ) separating it from the rest of the cell (بدون

In prokaryotic cell, DNA is a single strand (In prokaryotic cell, DNA is a single strand ( الشريط الشريط أحادى or double ) or double (أحادى

strand (strand ( الشريط الشريط ثنائى .DNA. But in eukaryotic cell, DNA is double strand.) DNA. But in eukaryotic cell, DNA is double strand (ثنائى

1). 1). ProkaryoticProkaryotic and and eukaryoticeukaryotic cells cells differ in size and complexity differ in size and complexity

DifferencesDifferences أوجه اإلختالف

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Cell Types : Prokaryotes Vs EukaryoteAccording to type of the genetic materials or nucleus, the biologist divided the cells into two types

Prokaryotes (Bacteria & viruses Prokaryotes (Bacteria & viruses cellscells

Euokaryotes (animal and plant Euokaryotes (animal and plant cells)cells)

Prokaryote : pro = before karyot = nucleus

Euokaryotes: Euo = true karyot = nucleus.

The bacteria and virus cells have

a primitive nucleus ,no nuclear membrane, nucleiod region

Plant and animals have real nucleus, surrounded with nuclear membrane.

The prokaryotic cells (bacteria and viruses) also have a very simples cell structure cell wall, cell membrane, cytoplasm, ribosome’s and nucleiod area for a very simple genetic material (DNA or RNA) and cilia or flagella.

The Euokayotic cells have a very complex structure and many cell organelles not found in prokaryoic cells such as: Mitochondria, ER ,Golgi body, lysosomes, plastids, vacules, centrioles,and very complex genetics materials DNA many chromosomes and RNAs

(A)- Prokaryotes(A)- Prokaryotes

الكائنات وحيدة الخلية ذات النواة الكائنات وحيدة الخلية ذات النواة البدائيةالبدائية

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Micro-organisms Micro-organisms األحياء الدقيقة

ProkaryotesProkaryotes

BacteriaBacteriaBacteriaBacteria ArchaeaArchaeaArchaeaArchaea

- Exist in extreme environments - Exist in extreme environments القاسية القاسية البيئات (hot and salty) (hot and salty) البيئات

- Exist in most - Exist in most environments environments

They are differing in some other They are differing in some other structuralstructural,, biochemical biochemical andand physiological physiological characteristics characteristics صفاتصفات

Types of ProkaryotesTypes of Prokaryotes

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1- Bacteria

ProkaryotesProkaryotes

Fig. 7.4 The prokaryotic cell is much simpler in structure, lacking a nucleus and the other membrane-enclosed organelles of the eukaryotic cell.

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غشاء غشاء بالزمىبالزمى

الجدار الجدار الخلوىالخلوى

شبه شبه نواةنواة

الريبوزوالريبوزوماتمات

الكبسولالكبسولةة

األسوااألسواطط

Prokaryotic CellProkaryotic Cell

CapsuleCapsuleCell WallCell WallPlasma Plasma membranemembrane

Cytoplasm Cytoplasm ((CytosolCytosol))

NucleoidNucleoidRibosomesRibosomes

Many prokaryotes (bacteria) Many prokaryotes (bacteria) secrete a sticky secrete a sticky protective layer called protective layer called capsulecapsule outside outside the cell wall, which has the the cell wall, which has the following functions following functions وظائفوظائف::

Adhere Adhere تثبيت bacteria cells to their substratum bacteria cells to their substratum السطح.. Increase bacteria resistance Increase bacteria resistance المقاومة to host defenses to host defenses مناِعة

..العائل StickStickتلصقتلصق)) ) ) bacterial bacterial cells cells togethertogether when live as when live as

coloniescoloniesمستعمراتمستعمرات .. Protect Protect تحمى bacterial cell.bacterial cell. Fig. 27.6

A) the bacterial capsuleA) the bacterial capsule

In all prokaryotes, the functions of the cell wall are as

following:

1. Maintains ظظتحافتحاف the shape of the cell,

2. Affords physical protection الطبيعية الطبيعية الحماية توفرتوفر الحماية

3. Prevents the cell from bursting ((إنفجارإنفجار) ) in a

hypotonic environment األسموزى الضغط ذات األسموزى البيئة الضغط ذات البيئة

.المنخفضالمنخفض

Most bacterial cell walls contain peptidoglycan peptidoglycan (a polymer of modified sugars cross-linked by short polypeptides).

The walls of Archaea lack ((تـفـتـقـدتـفـتـقـد) ) peptidoglycan.

B) The bacterial cell wallB) The bacterial cell wall

It is a tool for identifying تعريف specific bacteria, based on differences in their cell walls.

A)- Gram-positive (A)- Gram-positive (Gram +veGram +ve) bacteria:) bacteria:

Their cell walls have large amounts كبيرة of peptidoglycans كميةthat react with Gram’s stain (appear violet-violet-stained بنفسجيا بنفسجيا تُـصبغ .(تُـصبغ

Fig. 27.5a Page 529

The Gram’s stain: The Gram’s stain: صبغة صبغةجرامجرام

B)- Gram-negativeB)- Gram-negative (Gram -ve) bacteria:

their cell walls have no or small amount of peptidoglycan. So, do not react or very weakly react with Gram’s stain (do not appear stained الصبغة ال الصبغة تظهر تظهر )

Fig. 27.5b Page 529

The Gram’s stain: The Gram’s stain: صبغة صبغةجرامجرام

Gram Staining of BacteriaGram Staining of Bacteria

Gram +ve bacteria:Gram +ve bacteria: have Large amount of peptidoglycan have Large amount of peptidoglycan that stained that stained violet violet ((non-pathogenicnon-pathogenic ممرضة ممرضة غير ..((غير

Gram –ve bacteria:Gram –ve bacteria: Have small amount or no peptidoglycan Have small amount or no peptidoglycan (no staining) ((no staining) (pathogenicpathogenic ممرضةممرضة).).

Gram-negative species are pathogenic (Gram-negative species are pathogenic (ممرضةممرضة ) more threatening ) more threatening (( خطورة خطورة أكثر .than gram-positive species. ) than gram-positive species (أكثر

Gram-negative bacteria are commonly more resistant (Gram-negative bacteria are commonly more resistant ( ممانعة ممانعة أكثر ( (أكثرthan gram-positive species to antibiotics than gram-positive species to antibiotics الحياتية الحياتية للمضادات ..للمضادات

Prokaryotes reproduce (تـتـكاثر) only asexually (ال ) by binary fission (جنسيا البسيط الثـنائى .(اإلنقسـام

A single cell produce a colony of offspring.

Fig. 27.9 Page 531

Reproduction of Bacteria Reproduction of Bacteria البكتريا فى البكتريا التكاثر فى التكاثر

Nutrition of Prokaryotes Nutrition of Prokaryotes التغذية فى األحياء الدقيقة

• Prokaryotes are grouped Prokaryotes are grouped (فَـتI into four into four (صKٍن

categories categories (أنواع) according to how they according to how they

obtain energy and carbonobtain energy and carbon

Nutrition refers to how an organism obtains energy and a carbon source from the environment to build the organic molecules of its cells.

PhototrophsPhototrophs ( التغذية التغذية ضوئية Organisms that obtain energy from :(ضوئية

light.

ChemotrophsChemotrophs ( التغذية التغذية كيميائية Organisms that obtain energy :(كيميائية

from chemicals in their environment.

AutotrophsAutotrophs ( التغذية التغذية ذاتية Organisms that use CO2 as a carbon :(ذاتية

source.

HeterotrophsHeterotrophs ( التغذية التغذية متعدد Organisms that use organic :(متعدد

nutrients as a carbon source.

Nutrition of Prokaryotes Nutrition of Prokaryotes التغذية فى األحياء الدقيقة

PhotoautotrophsPhotoautotrophs ( الضوئية التغذية :(ذاتية use light energylight energy as energy source, and COCO2 2 as carbon source to synthesis (تخلق) organic compounds.

ChemoautotrophsChemoautotrophs الكيميائية التغذية :((ذاتية use chemical inorganic substancesinorganic substances as energy source, and COCO22 as a carbon source.

PhotoheterotrophsPhotoheterotrophs ( الضوئية التغذية :(متعدد use use lightlight as energy source, and organic substancesorganic substances as carbon source.

ChemoheterotrophsChemoheterotrophs ( الكيميائية التغذية :(متعدد use organic substancesorganic substances as a source for both energy and carbon.

There are four major modes of nutritionThere are four major modes of nutrition

Prokaryotic modes of nutritionProkaryotic modes of nutrition

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Based on Based on Carbon sourceCarbon source and and Energy sourceEnergy source that can be used that can be used by a prokaryote organism to synthesise organic compounds. by a prokaryote organism to synthesise organic compounds.

AutotrophsAutotrophs HeterotrophsHeterotrophs

Photo-Photo-autotrophautotroph

Chemo-Chemo-autotrophautotroph

Chemo-Chemo-HeterotrophHeterotroph

Photo-Photo-HeterotrophHeterotroph

COCO22 as Carbon Source as Carbon SourceOrganic compounds as Organic compounds as

Carbon SourceCarbon Source

- Light as energy source

-CO2 as C source

- Chemicals as energy source

-CO2 as C source

- Light as energy source

-Organic compounds as C source

- Chemicals as energy source

- Organic compounds as C source

ProkaryotesProkaryotes

Autotrophs Vs Heterotrophs According to type of cell feeding, the biologist

divided the cells into two type:

11-The Autotrophs -The Autotrophs

(plant cells)(plant cells)

2-Hetrotrophs 2-Hetrotrophs

(animal cells).(animal cells).

- Autotrophs :[atuo = self , trophos = feed ] self feeders they sustain themselves without eating other organisms they produce their organic molecules from CO2 and other inorganic row materials obtained from the environment. They use light (sun) energy to the synthesis of organic molecules.

The Heterotrophs (Animal cells): [Hetro = other or different, trophs = feed ] obtain their organic molecules from other, they cant make their organic molecules they live on compound produced by other organisms.

)for more information look at the book page176 , 6th ed(