Cell Structure & Organisation

Chapter Outline (a) identify cell structures (including organelles) of typical plant and animal cells from diagrams, photomicrographs and as seen under the light microscope using prepared slides and fresh material treated with an appropriate temporary staining technique: chloroplasts cell membrane cell wall cytoplasm cell vacuoles nucleus

Chapter Outline (b) identify the following organelles from diagrams and electronmicrographs: mitochondria ribosomes (c) state the functions of the organelles identified above (d) compare the structure of typical animal and plant cells

Chapter Outline (e) state, in simple terms, the relationship between cell function and cell structure for the following: absorption – root hair cells conduction and support – xylem vessels transport of oxygen – red blood cells (f) differentiate cell, tissue, organ and organ system

What is a cell? Building blocks of life Simplest units of life Chemical reactions in the cell keeps us alive

Cells White Blood CellsRed Blood Cells

Cells Embryonic Stem Cells

Other Examples of Cells Amoeba Proteus Plant Stem Red Blood Cell Nerve Cell Bacteria

Cells What does a cell consists of? Each living cell consists of living material called protoplasm. Protoplasm: Water makes up 70% of protoplasm Proteins Carbohydrates Fats

Protoplasm 1)Cell Surface Membrane 2)Cytoplasm 3)Nucleus

Cell Structures in Plant and Animal Cells nucleus cytoplasm cell membrane cell wall cell vacuoles ribosomes mitochondria chloroplasts

Animal and Plant Cells Animal CellPlant Cell Cell Structure and Function:

Animal Cell

Cell Surface Membrane Surrounds the cytoplasm of the cell Partially permeable membrane –Allows some substances but not all to move in and out of the cell

Nucleus Surrounded by a membrane called the nuclear envelope Contains one or more nucleoli Contains chromatin Functions of the nucleus: 1. Controls cell activities such as cell growth and the repair of worn-out parts 2. Essential for cell division Nucleolus

Cytoplasm Between the cell surface membrane and the nucleus Contains enzymes and organelles

Organelles in the Cytoplasm Mitochondria Ribosomes Chloroplasts (only in plant cells) Cell vacuoles

Mitochondria Aerobic respiration occurs in the mitochondria Energy production Energy used to perform cell activities such as growth and reproduction

Ribosomes Required for protein synthesis in the cell

Vacuoles in Animal Cells A vacuole is a fluid-filled space enclosed by a membrane Animal cells have many small vacuoles that contain water and food substances such as proteins and carbohydrates

Label and identify the diagram Pop Quiz! A B C D F E

Plant Cell Plant Cells:

Plant Cell

Differences Between Animal and Plant Cells Animal CellsPlant Cells Cell wall absentCell wall present Chloroplasts absentChloroplasts present Vacuoles are small, temporary in animal cells Vacuoles are large, sap- filled in plant cells

Cell Wall Surrounds the cell surface membrane Cell wall is made of cellulose Protects the cell from injury Gives the plant cell a fixed shape Cell wall is fully permeable

Chloroplasts Found only in plant cells Chloroplasts contain a green pigment called chlorophyll Chlorophyll is essential for photosynthesis, the process by which plants make food

Vacuoles in Plant Cells Plant cells usually have a large central vacuole which contains a liquid called cell sap Cell sap contains dissolved substances such as sugars, mineral salts and amino acids

Pop Quiz! Label and identify the diagram A B C F D E

Specialised Cells Red Blood Cell Root Hair Cell Nerve Cell Sperm Cell Egg Cell

Cell Differentiation The process by which cells develop special structures or lose certain structures to enable them to carry out specific functions. Hence, cells become differentiated to form specialised cells. The structure of each cell is adapted to perform the specific functions of the cell.

Cell Differentiation

How is cell structure related to cell function? 1) Red Blood Cell Cell StructureAdaptation to Function Contains haemoglobinHaemoglobin transports oxygen from the lungs to all parts of the body. No nucleusCarry more haemoglobin which leads to increased transport of oxygen. Circular biconcave shapeIncreased surface area to volume ratio of the cell. Hence, increased transport of oxygen.

How is cell structure related to cell function? Cell StructureAdaptation to Function Long hollow tubes (no protoplasm) Enables water to move easily through the lumen. Lignified wallsLignin strengthens the walls and prevents the xylem vessels from collapsing. 2) Xylem Vessel

How is cell structure related to cell function? Cell StructureAdaptation to Function Long and narrowIncreased surface area to volume ratio of the cell which leads to increased absorption of water and mineral salts from the soil. 3) Root Hair Cell Specialised Plant and Animal Cells:

How do cells work together in a multi-cellular organism? Organisation in Living Things:

Tissue A tissue is a group of similar cells which work together to perform a specific function. Examples of tissues: Muscle, the lining of the intestine, the lining of the lungs, phloem, root hair tissue Connective Tissue

Organ Different tissues may be combined together to form organs. An organ is a structure made up of different tissues working together to perform a specific function. Examples of organs: Heart, lung, brain, leaf, root Lungs

An organ is a structure made up of different tissues working together to perform a specific function.

Organ System Organs work together to form organ systems. Various systems work together to make up the entire organism. Examples of organ systems: Circulatory system, respiratory system, digestive system, nervous system and reproductive system Circulatory System

Organ Systems

SystemOrgans DigestiveEsophagus Stomach Small intestine Large intestine RespiratoryTrachea Lungs Organs work together to form organ systems.

Pop Quiz! Q1. Write out the order of cell organisation within an organism. Q2.Give an example of an animal system with the order of cell organisation stated above.

Organism Pop Quiz! Q1. Write out the order of cell organisation within an organism.

Intestinal cell  intestinal muscle  small intestine  digestive system  human Nerve cell  nerve tissue  eye  sensory system  bird Pop Quiz! Q2.Give an example of an animal system with the order of cell organisation stated above.