SCRAMBLED CELL

Mechanics:Unscramble

and win.

CHNOAIRDITOM

Mitochondria

EOIMSSI

Meiosis

LESUUCN

Nucleus

SMELSYOOS

Lysosomes

LELC EANBEMM

Cell Membrane

C

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Me nearbm

laW

CellWal

Brief History•The cell wall was discovered by Robert Hooke in 1665.

Structure•Cell wall is a rough,

generally flexible layer that surrounds some types of cells. It is situated outside the cell membrane.

Major Regions of the Cell Wall

•middle lamella•primary wall• secondary wall

Cell Wall Components

Cellulose• Cell walls are made of

specialized sugars called cellulose. • Cellulose is called a structural

carbohydrate (complex sugar) because it is used in protection and support.

Cross Linking Glycans

• Diverse group of carbohydrates that used to be called hemicellulose.• Play a major role in maintaining the

structural integrity of the wall by their tight association with cellulose microfibrils.

Peptic Polysaccharides

• determining wall porosity• providing a charged wall surface

for cell-cell adhesion • cell-cell recognition• pathogen recognition and others.

Proteins• The proteins may serve as

the scaffolding used to construct the other wall components.

Lignin•Lignin is primarily a strengthening agent in the wall. It also resists fungal/pathogen attack.

Suberin, wax, cutin•A variety of lipids are

associated with the wall for strength and waterproofing.

Water•Comprise 75-80% of the

cell wall.•Determines the flexibility

and extensibility of the wall.

Functions of the Cell Wall

• maintaining/determining cell shape• support and mechanical strength• prevents the cell membrane from bursting• controls cell growth and cell volume• physical barrier• carbohydrate storage• signaling

Ce ll anrbM me

Brief History• In 1855, C. Naegeli and

C.Cramer describe the cell membrane as a barrier essential to explain osmosis in plant cells.

The Cell Membrane• Also known as the plasma membrane is a

biological membrane that separates the interior of all cells from the outside environment.

• The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells.

Structure

Components of the Cell

Membrane

Lipids• Insoluable, fatty materials the cell

can use to construct membranes• Help to give membranes their

flexibility.• Used as energy source in the

form of fats.

Proteins• Proteins maintain and monitor the cell’s

chemical climate and assist in the transfer of molecules across the membrane.

• Cell adhesion molecules allow cells to identify each other and interact.

Functions• surrounds the cytoplasm of a cell.• protect the integrity of the interior of

the cell • serves as a base of attachment for

the cytoskeleton • serves to help support the cell and

help maintain its shape.

QUIZ TIME!

Direction: Provide the information being asked. Write your answers on a ¼ sheet of yellow paper. 1.The cell membrane is made up of _______ bilayer. 2.The tails of the bilayer are ______ 3.The heads are ______ 4. _________is a process where water can pass

across the cell membrane.

5.Constitutes most of the cell wall at about 75-80%. 6.They described the cell membrane as a barrier

essential to explain osmosis in plant cells. 7.He discovered the cell wall. 8-10. Give 3 functions of the cell wall.

Assignment:Read on the aids of cells for

locomotion. Write your findings on a ½ crosswise yellow paper