Cells

Who Gave cells their Name?

• Robert Hooke – He looked at thin slices of cork through the microscope. They reminded him of the small rooms in a monastery.

Who Gave us the Cell Theory?

• Schleiden – all plants are made of cells• Schwann – all animals are made of cells• Virchow – cell can only have come from other

cells• CELL THEORY: • 1. Cell is the unit of structure and function of all

living things. The Cell carries on the processes that are characteristic of all living things

• 2. Cells arise only from other cells

What do all living things need in order to function?

•Energy

• Energy comes from the chemical reactions that take place in the cell.

Chemical activities

• In one part of the cell are dependent on reactions taking place in another part of the cell.

• These reactions are related in some way to the functions considered to be cahracteristic of all living things.

Characteristics of all living things:

• Nutrition – food molecules are necessary to supply energy and building materials in cell

• Digestion – break down food - Enzymes speed up the process• Absorption- cell take in water, food, ions & other

material• Biosynthesis – manufactures organic substances ( what

are They?) - these are organized into their own cell material - Necessary for growth and repair.

• Respiration – release of energy from food• Excretion – waste material from cell’s activities are

passed from the cell to its’ environment - metabolic wastes - digestive wastes• Secretion – certain cell synthesize molecules of

substances such as vitamins and hormones. When secreted, these substances affect activities of other cells

• Response – cell activities may change in response to stimuli from the environment

• Reproduction – cells divide in an orderly fashion.

Animal Cell:1. Microfilament2. Cell Membrane3. Centriole4. Golgi Apparatus5. Nucleolus6. Nuclear Membrane7. Chromatin8. Ribosome9. Lysosome10. Vacuole11. Nucleus12. Microtubule13. Cytoplasm14. Endoplasmic Reticulum15. Mitochondria

Animal Cell’s Parts and Functions

Microfilament- composed of protein/part of the cell’s cytoskeleton gives support to the cell

Cell Membrane – also called plasma membrane/ controls molecules entering and leaving the cell

Centriole – functions in cellular reproductionGolgi aPParatus (Golgi Body) “Protein packaging factory”NucleOlus – controls protein synthesisNuclear Membrane – surround the nucleusChromaTIN – made of DNA and protein carries hereditary traitsRIBosome – center of protein synthesis where proteins are madeLySOSome – “Suicide sac” contains protein digesting enzymes

Animal Cell cont.

Vacuole – storage of food, water and wastes Contractile vacuole- found in unicellular organisms to

eliminate excess waterNucleus – control center of the cellMicrotubule – gives support/found in organs of locomotion ie. Cilla, flagella, sperm tailsCytoplasm – found between the cell membrane and the nuclear

membrane (Jelly like liquid)Endoplasmic Reticulum – known as the ER/ system of canals to move

materials throughout the cellMitochondria – powerhouse of the cell / center of cellular

respiration

Plant Cell:1. Ribosome2. Microfilament3. Nucleus4. Nuclear Membrane5. Golgi Apparatus6. Microtubule7. Cell Wall8. Cell Membrane9. Endoplasmic Reticulum 10. Chloroplast11. Lysosome12. Cytoplasm13. Mitochondria14. Vacuole

Plant Cell Parts and Function

• Ribosome – center of protein synthesis• Microfilament – part of the cell’s cytoskeleton, gives support

to the cell• Nucleus – control center of the cell• Nuclear Membrane – surrounds the nucleus• Golgi apparatus – protein packaging factory• Microtubule – part of the cells cytoskeleton, give support• Cell Wall – surrounds cell membrane, protects and supports

the cell• Cell membrane – controls materials entering and leaving the

cell

Plant cell cont.

• Endoplasmic Reticulum – series of canals which allows for the movement of molecules throughout the cell

• Chloroplast – site of photosynthesis, contains the pigment chlorophyll for trapping light energy

• Lysosme – suicide sac contains protein digesting enzymes• Cytoplasm – located between the cell membrane and the

nuclear membrane• Mitochondria – powerhouse of the cell – center of

cellular respiration• Vacuole – storage of food, water and wastes.

Inside the Cell

• Some simple organisms are made up of only one cell, while most plants and animals are made up of huge numbers of cells.

• Each cell has its own role to play in the life of the plant or animal and it is adapted to perform those particular functions.

• Your skin, your bones, your muscles and your brain are made of cells

• There are over 200 different types of cells in your body.

Inside a cell

• A thin skin called a membrane, holds the cytoplasm together. Animal cells have soft membranes made of fat and proteins.

• The membrane gives the cell shape, and also lets certain chemicals like oxygen and food substances pass through and stops other things from entering. It lets waste material out again.

• Cytoplasm is a watery, jelly like mixture of chemicals

• Cytoplasm acts as a storeroom of molecules for growing and repairing the structures inside the cell. Small structures called organelles are present in the cytoplasm. They produce hormones, enzymes and other substances which are released for use inside the cell and also elsewhere in the body.

• Most plant and animal cells contain an inner part, called the nucleus. It controls what the cell does and how it develops. The nucleus can be seen under a microscope. The vacuole is a space in the cell containing air, liquids or food particles. Animal cells usually have small vacuoles. All plant cells have vacuoles and liquid inside them is called cell sap.

• Plant cell vacuoles are quite large. Water collects in the vacuoles when the plant is watered and this makes the plants rigid (or stiff).

• Without enough water, there is less pressure in the vacuoles and the plant wilts.

• Plant cells also contain chloroplasts, which are tiny disks full of a green substance called chlorophyll. They trap the light energy that plants need for making food by photosynthesis.