CELLS

By Miss Burd and Mrs. Tilicki

CELLS – all living things are made up of cells!

Cells – the basic unit of structure for our bodies

Organelles

Inside a cell are tiny cell structures called organelles.

Each organelle carries out a specific function within a cell.

Cell Wall in a plant cell Before you can enter a

cell, you must pass through the cell wall.

The cell wall is a rigid layer of nonliving material that surrounds the cells of plants and other organisms.

The cell wall is made of cellulose.

Animal cells have no cell wall

Animal cell

Cell Membrane All cells have a cell

membrane. This is just inside the cell

wall or on the outside of the cell without a wall – it separates the cell from its environment.

It controls what substances come into and out of a cell

Cell Wall VS Cell Membrane

The cell membrane is very thin. The cell wall is thick. The cell membrane is a living part of

the cell. The cell wall is a nonliving part of the

cell The cell wall gives shape to the cell.

Nucleus

The nucleus is the cell’s control center.

It directs all of the cell’s activities.

Nuclear Membrane

The nucleus is surrounded by a nuclear membrane that protects the nucleus.

Plant Cell

Animal Cell

Animal Cell VS Plant Cell

Differences:• Plant cell has a cell wall

• Animal cell doesn’t have a cell wall

• Plant cell has Chloroplasts

• Animal cell doesn’t have Chloroplasts

Chromatin Thin strands called

Chromatin float in front of the nucleus.

Chromatin contains genetic material (DNA) that directs the function of the cell.

Organelles in the cytoplasm

As you leave the nucleus, you find yourself in the cytoplasm of a cell.

This is a forever moving jelly like substance that contains organelles that produce energy, build and transport needed materials and stores and recycles wastes.

Mitochondria- “powerhouse”

This organelle produces energy to help the cell function. The more active the cell, the more mitochondria it has.

Endoplasmic Reticulum

Maze of passageways that carry proteins and other materials from one part of the cell to another.

Ribosomes – making a protein

Attached to the surface of the endoplasmic reticulum are ribosomes. These ribosomes produce proteins and release them into the wall of the endoplasmic reticulum. They are then transported by Golgi Bodies.

Golgi Bodies

Golgi bodies are like the cell’s mail room.

They receive proteins and other newly formed materials from the endoplasmic reticulum, package them and distribute them to other parts of the cell.

Chloroplasts Chloroplasts are found

in the cytoplasm of plant cells.

Chloroplasts capture the energy of the sun and use it to produce food for the plant.

It is chloroplasts that give a plant its green color.

Vacuoles Storage center for a

cell. (Some animal cells don’t have vacuoles.

Store food and other materials needed.

Sometimes store waste.

In plants, store water – when well watered, they are full… when not well watered, the plant wilts.

Lysosomes

Small round particles that break down food.

More common in animal than plant cells.

Clean the cell!

Bacterial cells

Bacteria cells are smaller than animal and plant cells

It does not contain a nucleus.

It contains a cell membrane and a cell wall, but the only organelle is ribosomes.

Bacteria Cells Bacteria live on and in animals and plants. Bacteria are used to make many of the dairy

products you enjoy, including yogurt, cheese, and milk.

There are more bacterial cells in your body than there are human body cells. Dead or weakened bacteria and virus are used for making helpful vaccines.

Birds and other animals are common sources of pathogenic (disease causing) bacteria such as Salmonella and Campylobacter.

Bacterial Cells Bacteria are the cause of diseases such as tetanus. Many

bacterial diseases can be treated with specialized molecular compounds, known collectively as antibiotics.

Most bacteria are good. 99% of all bacteria are helpful. Only a few cause disease.

By breaking down dead organic matter like trees and other plants, bacteria help to make the nutrients available again to other living organisms.

Scientists estimate that bacteria produce nearly half the oxygen found in the atmosphere.

Bacteria play an important role in the cycling of minerals, by taking elemental materials such as nitrogen and carbon, and converting them into molecular compounds that can then be used by plants and animals.

Bacterial Cells Some types of bacteria are used to break down oil after

ecologically damaging oil spills. Helpful bacteria are used to purify water at sewage treatment

plants. Some bacteria help our bodies with digestion and to produce

needed vitamins. These bacteria also help us by destroying pathogenic bacteria that invade our bodies.

Bacteria are found everywhere, from the deepest parts of the oceans to the tallest mountains on Earth.

The air is full of bacteria. Some bacteria spend their whole lives in the atmosphere, reproducing and growing in the clouds above our heads.

Bacteria love to live where the living is easy. Anything with dead or decaying matter is a great home for bacteria. We humans have millions of bacteria living in and on our bodies including our skin, our mouths, our intestines, and our stomachs.

Virus Viruses are non-living

microscopic particles that attack healthy cells within living things.

Viruses are not alive, so they do not have a need for food like living things.

Viruses do not have an organized cell structure.

They are so light that they can float in the air or water, be passed on to other organisms if touched, and fit anywhere.

Virus - Influenza

Specialized Cell: There are many cells in plants and animals that perform special functions.

Nerve Cell – sends messages throughout your body.

Red blood cells are thin and flexible which allows them to fit through tiny blood vessels.