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1. Transport protein
•Spane the membrane to provide a hydrophilic channel across the membrane
•There are two types of protein ;
- Channel protein (Allow water molecules or small ions to flow very quickly from one side pf the membrane to the other).
- Carrier protein (Shuttle a substance from one side to the other by changing shape and some of these protein hydrolyse ATP as an energy source).

2. Enzymatic Activity
•Protein may be an enzyme with its active site exposed to substances in the adjacent molecule and carry out sequential steps of a metabolic pathway.

3. Signal Transduction
•A membrane protein may have a binding site with a specific shape of a chemical messenger.
•The chemical messenger(signal) may cause a conformational change in the protein that relays the message to the inside of the cell.

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1)COMPACT BONE:

Bone are divided into TWO types:

1. Compact Bone

2. Spongy bone

A typical bone has an outer layer of compact bone surrounding spongy bone.

STRUCTURE:

•Consists of bone matrix which is made up of collagen fiber and inorganic material that secreted by osteoblast.

•The combination of hard mineral and flexible collagen makes bones harder than cartilage.

•Osteoblast function to secrete bone matrix.

•Osteoblast become less active when they matured (matured osteoblast is called as osteocytes).

•Osteocytes function to maintain the bone matrix.

•It is made up of numerous cylinders.

•Each cylinder is called as Haversian system or osteon.

•Each Haversian system is made up of concentric  circles called lamellae.

•Each Haversian canal containing  blood vessel (artery and  vein) and nerve.

•Fine channels called canaliculi contain cytoplasmic strands which connect lacunae to each other.

•Volkmann canals connect the Haversian of adjacent osteons to each other.

Distribution:

• Form skeletal structure in most vertebrates

Functions:

1) Give body shape and provide framework for support e g. skeleton

2) Act as reservoir for calcium and phosphorus

3) Support and protect the internal organ

4) Allow skeletal muscles attach to bones

2)HYALINE CARTILAGE:

-glass-like (hyaline) but translucent cartilage found on many joint surfaces.

Trachea and bronchi, End of some(long) bones, Invertebral disc of backbone, Tip of nose Outer ear,

Connect the ribs to sternum,

COMPOSITION

·  Cell Chondrocyte
·  Matrix Soft & Elastic Matrix (Chondrin)
·  Fiber Collagen

Structure

·Protected By Outer Perichondrium Layer Perichondrium Layer produce Chondroblast.Chondroblast later become Chondrocyte (cartilage cell in general) enclosed in a
space->lacunae which surrounded by a capsule
1.Chondrocytes near the outer cell flatten in shape but the inner region are angular
2.Chondrocyte are enclosed in lacunae
3.Each lacuna has 1/2/4 chondrocyte
4.Chondrocyte secrete soft & elastic matrix – Chondrin, and Chondrocyte is embedded in chondrin.

o Chondrin?
o Made up of chondroitin sulphate (secreted by Chondrocyte) and collagen fibers
Semi-transparent materials which give soft and elastic characteristic
·There are no blood vessels, nerves and lymph penetrate within matrix of cartilage.Cartilage obtain Oxygen and nutrients by diffusion from the surrounding blood vessels (diffuse from Perichondrium through the matrix)

Function

· Soft and elastic matrix gives flexible support to the body
· Cover end of bones and reduce friction between joints
· Form embryonic skeleton in many bony vertebrates
· Form skeleton of cartilaginous fish
· Elastic and compressible tissue （cushioning properties ）

Comparison Between Hyaline Cartilage and Bone

--Hyaline Cartilage

Cartilage Cell is called Chondroblast
Lacunae are not connected to each other
Chondroblasts are scattered and contained in a space called capsular lacuna
Matrix is compressible and elastic/flexible
No blood vessel, lymph vessel and nerve fibres (present only inside the Perichondrion layer)
Have collagen and elastin fibrils
Function to reduce friction between joints during movement
Matrix composed of chondroitin sulphate and collagen fibers
Each lacuna has 1/2/4 chondrocytes

-- Bone
Bone cells is called osteoblasts
Lacunae are connected to each other by canaliculi
Osteoblasts contained in lacunae and are arrange in concentric layer called lamellae
Matrix is very strong, compact and hard calcified
Have blood vessel, lymph vessel and nerve fibres in the Harvesian canal
Have only collagen fibrils
Function is to provide mechanical support, to protect internal organ
Matrix is composed of mineral salts and fiber
Each lacuna has 1osteocytes

3)WHITE BLOOD CELL (LEUCOCYTES)

-Colorless, Have nuclei and mitochondria, Irregular shape
-Found in bone marrow and lymph nodes

Function: Fight functions in various ways to protect the body from diseases

2 TYPES：AGRANULOCYTE & GRANULOCYTE

GRANULOCYTES

-Have an irregularly lobed nucleus (Polymorph shape,
S-shaped or double lobed) and granular cytoplasm
-Amoeboid
-Mature in bone marrow

1.Neutrophil (phagocytes)
-Most abundant of the leucocytes
-Multi-lobed nucleus and granules
-Carry out phagocytosis to engulf and digest invading bacteria and dead cells
2.Eosinophil
-Have a double-lobed nucleus and granules
-Regulate the allergic response
3.Basophil
-Have S-shaped nucleus and granules
-Secrete histamine which is involved in inflammation of damaged tissues and allergic reaction
-Produce heparin (anti-clotting protein) which helps to prevent blood clotting

AGRANULOCYTES

-Non-granular cytoplasm, smooth rounded or bean-shaped nucleus
-Mature in lymph nodes
1.Lymphocyte
-Smallest type of leucocytes
-Large spherical nucleus with little cytoplasm
-Formed in lymph nodes of the lymphatic system
-Produce immune response against foreign substances
-Specialised as B-lymphocytes

Produce antibodies to destroy pathogens or to neutralise toxin

-T-lymphocytes
Destroy infected cell

2.Monocyte
-Largest type of leucocytes
-Has kidney-shaped (bean-shaped) nucleus
-Formed in bone marrow
-Phagocytes= Carry out Phagocytosis to engulf and digest invading bacteria and dead cells

DIFFERENCE WHITE BLOOD CELL (LEUCOCYTES) AND RED BLOOD CELL (ERYTHROCTES)

--WBC

Presence of nucleus
Function in defence system
Irregular / amoeboid shape

-- RBC
Absence of nucleus
Function in transport system
Biconcave / Fix shape

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FUNCTION OF CARBOHYDRATES ON CELL CELL RECOGNITION 

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FUNCTION OF CARBOHYDRATES ON CELL CELL RECOGNITION 

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located at the outer surface of plasma membrane .
function : act as identification tag

combine with :
-protein -> form glycoprotein
-phospholipid -> form glycolipids

function glycoprotein
-important for cell-to-cell recognition

function glycolipid
-maintain stability of the membrane and to facilitate cell–cell interactions.
-act as receptors for viruses and other pathogens to enter cells.

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Endoplasmic reticulum is a network of membranes inside a cell through which proteins and other molecules move.

Proteins are assembled at organelles called ribosomes.

When proteins are destined to be part of the cell membrane or exported from the cell, the ribosomes assembling them attach to the endoplasmic reticulum, giving it a rough appearance.

FUNCTION

to produce proteins for the rest of the cell to function

RER makes secretory proteins

STRUCTURE

largely made of sheets a two-dimensional array of flattened sacs that extend across the cytoplasm.

HOW RER PERFORM ITS FUNCTION

RNA moves from the nucleus to a ribosome on the surface of the RER.

As the ribosome builds the amino acid chain, the chain is pushed into the cisternal space of the RER.

When the proteins are complete, they collect and the RER pinches off a vesicle.

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VASCULAR TISSUE :XYLEM

FUNCTION

1. Conduct water and dissolved minerals water upward from roots into shoots.

2. Provide structural support to plants

TYPES OF XYLEM TISSUE:

1. Tracheids
2. Vessel elements
3. Fibres
4. Xylem parenchyma

TRACHEIDS

1. Each cell is elongated with tapered ends.
2. Have numerous pits on the ends.
3. Water moves from cell to cell mainly through pits
4. Cylindrical - empty cavity in central cell
5. Cell is dead at maturity
6. Function : Support the plant and transportation

VESSEL ELEMENT

1. Cylindrical - empty in central of cell

2. Cell fused together to form long tubes

3. Wider , shorter and less tapered than tracheids.

4. Cell wall is thickened and lignified.

5. Cell is dead at maturity

6. The ends are perforated , enabling water to flow freely.

Vessel elements is more efficient than tracheids. Why?

1. Vessel elements are joined end to end without cross wall to form along tube structure.

2. The ends are perforated (hole) , enabling water to flow freely

3. Lumen of xylem are narrow, enabling creation of capillary action

4. Lignification of xylem vessel walls:
- makes it impermeable to water, promoting continuous flow of water and ions
- creates strength and rigidity to provide mechanical support for plants.

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STRUCTURE

💮 Centriole grow out from a centrosome
💮A pair of cylindrical structure located within the centrosome of an animal cell
💮 Centriole is made up of microtubule
💮Composed of nine sets of triplet microtubules arranged in ring
💮Centriole is organelle without membrane

FUNCTION

✳️Organize microtubule assembly during cell division especially in animal cell

CENTROSOME

🌺The region near the nucleus where the cell's microtubules are initiated
🌺An animal cells has a pair of centrioles within its centrosome

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-Proposed by S. J singer & G. L. Nicolson(1972).
-Composed by two layers of phospholipids with globular proteins embedded in the bilayer.

Fluid refers to:

Phospholipid can move laterally or flip flop

Protein are free to move laterally

Mosaic refers to:

The various proteins are embedded in or attached to phospholipid bilayer

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Phloem consist of 4 different types of cells:
1) Sieve Elements (sieve cells, sieve tubes)
2) Companion Cells
3) Fibres
4) Parenchyma Cells

Sieve Cells
-long
-slender
-have overlapping ends
-uniform in structure
-present in all plant cell walls

Sieve Tubes
-found in flowering plants
-do not have nucleus
-thin cell wall
-consists of sieve plates have sieve pores to allow cytoplasmic connection to transport photosynthetic products across the sieve tubes

Companion Cell (Transfer Cells)
-important for the survival of sieve tubes
-are metabolically active and carry out cellular respiration to produce energy for the living cells and to allow the photosynthesis products to be transported by the sieve tubes
-cytoplasm of companion cells and the sieve tubes are connected through plasmodesmata

Fibres
-dead sclerenchyma tissues that are found between the sieve tubes
-provide mechanic support

Parenchyma Cells
-found in between the sieve tubes
-store food such as starch, oil, fats, other nutrients

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Major - phospholipids
- globular protein
Others-carbohydrate
- cholestrol

i. Phospholipids: the most abundant lipids in the plasma membrane

Hydrophobic tails

Non polar

Hydrophobic (water) which face each other in the middle of the bilayer; thus not exposed to water

Hydrophilic heads

Polar

Hydrophilic (attract water) which face the cytoplasm and extracellular matrix;thus exposed to water

Function Of Phospholipids

1. Phospholipids can move whithin in phospholipid bilayer by lateral movement or flip-flop.
2. The type of hydrocarbon tails in phospholipids affects the fluidity the plasma membrane

The membrane remains fluid to a lower temperature if it is rich in phospholipids with unsaturated hydrocarbon tailstails

Because of kinks in the tails whete double bonds are present.

Unsaturates hydrocarbon do not pack together as closely as saturated hydrocarbons

This makes the membrane more fluid.

Thats why cold blooded animals(body temperature that depends on surrounding) has abundant unsaturated fatty acids.

Unsaturated fat melt at lower body temperature compare to saturated fat.

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Nerve cell has two distribution which is brain and spinal cord.

The function of nerve cell in body is :
-to receive nerve impulses from interneurons and transmit impulses to effector (muscle and gland).

- specialized to produce and conduct electrochemical events or impulses between receptors and effectors.

Main structure of Motor Neuron are :

- Dendrite
- Cell body

- Axon

1. DENDRITE

Slender branching conduct impulse towards the cell body (to obtain information from other cells and carry that information to the cell)

2. CELL BODY

Have nucleus and the perikaryon (cytoplasm and organelles surrounding the nucleus)

Nissl’s granules which are groups of ribosomes and rough endoplasmic reticulum, and Golgi apparatus are present.

3. AXON

Nerve fiber which conduct impulse from the cell body to another neuron.

The end of an axon breaks up into many fine branches with swollen endings called synaptic.

Myelin Sheath

Structure:

Some axons are completely surrounded and insulated by a fatty myelin sheath.

Myelin sheaths are formed by a type of cells called Schwann cells.

Function:

Allows electrical impulses to transmit quickly and efficiently along the nerve cells.

Node of Ranvier

Structure:

Myelin sheath is interrupted at intervals along the axon by nodes of Ranvier

Function:

To speed up the transmission of impulse.

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Function: -Collenchyma serve as support and strength the tissue
-Give support especially to herbaceous plant
-Some have chloroplast to carry out photosynthesis
-Provide mechanical support to new developed organs especially roots and stems
-can store starch as food

Distribution: - 0uter region of cortex
-Below the eperdemis of leaves , petioles
- Leaves vein
-Young stem
-They usually occupy the peripheral layer of cortex in dicotyledons

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Types and Structures of Muscle Cells - Skeletal Muscles, Cardiac Muscles, and Smooth Muscles

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CARDIAC MUSCLES
Structure
🔹Striated like skeletal muscle but have branches
🔹 cells connected with bridge & intercalated disc (f(x) : relay impulse between cell during heartbeat/ help synchronize heart contraction)
🔹 1 or 2 nuclei (centrally located) per fiber
Function
🔹 Responsible for contraction of the heart
Distribution
🔹 Cardiac tissues of wall of heart

SMOOTH MUSCLE
Structure
🔹Has spindle-shaped, elongated fibres with pointed ends
🔹Nuclei is located at the central.
Function
🔹 Responsible for involuntary actions of the body.
🔹 E.g. When the smooth muscle of the intestine contract, food is moved along the digestive tract
Distribution
🔹 Walls of internal organs - digestive tract and urinary bladder

SKELETAL MUSCLE
Stucture
🔹The cells are elongated and cylindrical with blunt ends
🔹Have many nuclei (multinucleated) per fiber st peripheral of the cell
🔹Unbranched
🔹 Have striation / stripes that result from :
1. The orderly arrangement of Actin and Myosin filament within the muscle
2. Repetition between dark and light band
🔹 Myofibril consist of :
1. Myosin (THICK LAYER)
2. Actin (THIN FILAMENT)
🔹 SARCOLEMMA - Membrane for muscle fibre
🔹 SARCOPLASM - Cytoplasm which contain many mitochondria
🔹 SARCOMERE - Functional unit of muscle fiber
Function
🔹Responsible for voluntary movements
Distribution
🔹Attached to the bones by tendons

Similar & Difference
🔵 SKELETAL
🟠 SMOOTH
🔴 CARDIAC

🌱Type of control :
🔹Voluntary
🔸Involuntary
♦️ Involuntary

🍀Shape of fibers:
🔹Elongated,cylindrical,blunt ends
🔸Elongated,spindle-shaped,pointed ends
♦️ Elongated, cylindrical,fibers that branch and fuse

🍁Striations :
🔹Present
🔸Absent
♦️ Present

🌲Number of nuclei per fiber:
🔹Many
🔸One
♦️ One or two

🍃 Position of nuclei:
🔹Peripheral
🔸Central
♦️ Central

⚡Speed of contraction:
🔹Most rapid
🔸Slowest
♦️ Intermediate

💧Resistance to fatigue:
🔹Least
🔸 Greatest
♦️ Intermediate

ORDERLY ARRANGEMENT

YOSIN

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- Found between phospholipids molecules

FUNCTION CHOLESTEROL:

-regulate membrane fluidity by restricting the movement of phospholipids (stabilize membrane structure)

-At warm temperature (37⁰C), cholesterol makes the membrane less fluid by
restraining the  movement of phospholipids.

-At low temperature, cholesterol also hinders close packaging of phospholipids thus maintain the membrane fluidity. Prevent phospholipid from become solidify.

-Act as temperature buffer for the membrane fluidity, resisting changes in membrane fluidity that can be caused by changes in temperature

- Cholesterol reduces membrane fluidity at moderate temperatures, but at low temperatures hinders solidification.

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LYSOSOME STRUCTURE :
-lysosomes are spherical, membrane bound organelles that are generated by the golgi apparatus.
-acidic membrane-bound organelles found within cells,usually around 1 micrometre in length
-contain hydrolytic enzymes to digest macromolecules.
-lysosomal enzymes can hydrolyze proteins,fats, polysaccharides and nucleic acids

FUNCTION :
-involve in autophagy
-involve in autolysis
-play an important role in phagocytosis. When macrophages phagocytose foreign particles, they contain them within a phagosome.
-the phagosome will then bind with a lysosome to form a phagolysosome.
-help to defend against pathogen entry via endocytosis by degrading pathogens before they reach the cytoplasm.

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STRUCTURE OF GOLGI BODY:

-consists of cisternae (stack of flattened membrane-bounded sacs)
-The membrane of each cisternae separates its internal space from the cytosol.

- Golgi body stack has 'cis-face' (facing endoplasmic reticulum/nucleus) and 'trans-face' (facing plasma membrane)

Function of 'Cis-face' & 'Trans-face';

Cis-face - received carbohydrate/protein/lipid from        transport vesicle by fusing with transport vesicles buds from ER
Trans-face - modify,package, and sort molecule in vesicles & transport out of the golgi body

FUNCTION OF GOLGI BODY:
~synthesis lysosome
~transport the materials to the cell surface membrane for secretion
~produces polysaccharide in plant cell

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The main function of epithelial cell is to act as protection, the epithelial layer of skin covers the entire body and protects from mechanical injury, chemicals, bacteria and fluid loss.

There are 4 types of epithelial cell we learned in our syllabus

1) SIMPLE SQUAMOUS

-Flattened, thin and single layer thick cell.
-Attached to the basement  membrane
-Have disk shaped central nuclei
- Its function is to facilitate diffusion of gases and small molecules such as oxygen and carbon dioxide
- It can be found at Linings of blood vessels blood capillary walls, alveoli of the lungs ,mouth cavity and bowman capsule

2) SIMPLE CUBOIDAL
-Cubical in shape/ dice shape cell and single layer cells

- Its function is to secrete and absorb water and small molecule
- It can be found at the lining of kidney tubules and lining of gland ducts:  Thyroid & salivary glands

3) SIMPLE COLUMNAR
- Elongated and single layer cells
- Relatively large cytoplasmic volume
- Nucleus oval shape at its basal end
- Some have cilia or microvilli
- Its function is to secrete mucus , absorb nutrients and provide protection due to thick cell layer
- Ciliated type   = the filter of foreign particles in trachea
- Microvilli type = increase surface area for reabsorption
-It can be found at linings of small intestine / most digestive tract ,  upper part of respiratory tissues, oviduct(fallopian tube) and nasal cavity

4)  STRATIFIED SQUAMOS
-It has several layers of cells and surface cells are flattened
-The lower cells are cuboidal and metabolically active
-Its function is to protect against abrasion, drying out of cells and infection
- It can be found at outer layer of skin, mouth and vaginal lining and lining of oesophagus

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STRUCTURE OF NUCLEUS:
-Largest organelle.
-Outer membrane is connected with endoplasmic reticulum (ER).
-Has a number of part which is
>nuclear envelope
>nucleolus
>nuclear pore
-Plural: nuclei. (which is the other name of nucleus).
-Has a shape like spherical or oval.
-Has average 5μm(5micrometres) in diameter.
-Contains DNA that carry genetic material.

FUNCTION OF NUCLEUS:
-Acts as the control centre of the cell through the production of mRNA and protein synthesis.
-Retains the genetic material of the cell in the form of DNA or chromosomes.
-Synthesizes rRNA and ribosomes in the nucleolus.
-Starts the process of cell division.

STRUCTURE OF NUCLEOLUS:
-Has a spherical shape which is found within the nucleoplasm.
-Has a dense mass of granule inside the nucleus.
-Has one or more nucleoli may be present.
-Non-membranous structure.
-Contain DNA,RNA and protein.

FUNCTION OF NUCLEOLUS:
-Acts as the manufactures of rRNA.
-Combine protein with rRNA to form ribosome.

STRUCTURE OF NUCLEAR ENVELOPE:
-Have two membranes that is perforated by nuclear pores.
-At the lip of each pore, the inner and outer membranes of the nuclear envelope are continuos.

FUNCTION OF NUCLEAR ENVELOPE:
-Encloses the nucleus, separating its contents from the cytoplasm.
-Controls the passage of various susbstance into and out of the nucleus.
-Nuclear pores allow exchange of substances between the nucleus and cytoplasm.

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SMOOTH ENDOPLASMIC RETICULUM CHARACTERISTICS :
~ single membrance organelles
~ consists of more tubular sacs
~ ribosomes are not present
~ membrance of SER contains many embedded enzymes
~ connected to the nuclear envelope (like RER)

FUNCTIONS :
~ synthesis of lipids including cholesterol and phospholipids
- which are used in the production of new cellular membrance
~ carries out the metabolism of carbohydrates and steroids
~ regulates calcium ion storage in muscle cells
~ contributes to the detoxification of drugs and harmful chemicals

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FUNCTION MITOCHONDRIA:
-sites of ATP synthesis / sites of aerobic cellular respiration.

EXPLANATION:
-convert chemical energy from food to ATP.
-the metabolic process that generates ATP by extracting energy from sugar,fats and other fuels with help of oxygen.

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CHLOROPLAST
GRANUM : Stack of Thylakoids to maximize light absorption
STROMA : Contains the enzymes, ribosomes, chloroplas DNA, and starch grains.
Stroma lamellae : Connects and separates thylakoid stacks
THYLAKOID : Contain photosynthethic pigments that function to captured light energy.
INTERMEMBRANE SPACE : Space between outer membrane and inner membrane.

FUNCTION:
plant cell organelles that convert light energy into relatively stable chemical energy via the photosynthetic process.