Cell Structure and Organization

CELL STRUCTURE AND ORGANIZATION: 

Chapter 1 CELL STRUCTURE AND ORGANIZATION

Characteristics of Life: 

Characteristics of Life Homeostasis Organization Metabolism Growth Adaptation Response to stimuli Reproduction

Classification of living things: 

Classification of living things Kingdom Phylum Class Order Family Genus Species

The scientific method: 

The scientific method Observe Hypothesize Experiment Accept/reject hypothesis Cycle repeats

The Discovery of the Cell: 

The Discovery of the Cell Robert Hooke – first to see and identify cork “cells.” (1665)

Anton van Leeuwenhoek (1660): 

Anton van Leeuwenhoek (1660) Single lens microscope Pond water

Matthias Schleiden (1838): 

Matthias Schleiden (1838) German botanist Plant cells

Theodor Schwann (1839): 

Theodor Schwann (1839) German biologist Animal cells

Rudolf Virchow (1855): 

Rudolf Virchow (1855) German physician New cells could only come from the division of existing cells

Cell Theory: 

Cell Theory Every living organism is made up of at least one cell. Cells are the basic structural and functional units of living organisms. All cells arise from pre-existing cells.

General cell structure: 

General cell structure

3 things in every cell…: 

3 things in every cell… surrounded by a barrier, cell membrane At some point in their life they contain nucleus The jelly-like mixture that fill up the space between cell membrane and nucleus: cytoplasm Together they are what makes up protoplasm.

Cell membrane (aka plasma membrane): 

Cell membrane (aka plasma membrane)

Cell membrane (aka plasma membrane): 

Cell membrane (aka plasma membrane) made of phospholipids and proteins . Partially permeable allowing only some substances to pass through while blocking other substances. separates the cell from the surrounding environment and controls the movement of substances going in and out.

Cytoplasm: 

Cytoplasm Jelly- like mostly water and proteins such as enzymes many membrane- bound structures collectively known as organelles float inside Some bound by a single membrane, some by a double membrane Cytoplasm = organelles + cytosol Most metabolic activities (which are chemical reactions) occur here.

The Nucleus: 

18 The Nucleus Nucleolus Pores Chromatin Threads (Chromosomes) Nuclear Envelope

Nucleus: electron micrograph: 

19 Nucleus: electron micrograph Plasma Membrane Nucleus Nuclear Pores

Chromosomes: 

20 Chromosomes Nucleoli Nucleus Cell Wall Chromosomes

Nucleus – what’s inside: 

Nucleus – what’s inside nuclear envelope , a double membrane with pores in it. nucleoplasm , similar to cytoplasm, a jelly-like liquid that contains nucleotides and enzymes . It surrounds the nucleolus, chromatin and chromosomes. nucleolus (plural: nucleoli ): a dense area where ribosomes are made. chromatin : threads of uncoiled DNA and proteins, freely floating in the nucleoplasm chromosomes : highly coiled DNA, forms during cell division .

Nucleus: 

Nucleus most of the nucleic acids made and stored here DNA = deoxy ribo nucleic acid RNA = ribo nucleic acid DNA is the physical carrier of inheritance  nucleus controls important cell activities such as growth and repair, cell division, etc.

Mitochondria (singular: mitochondrion): 

Mitochondria (singular: mitochondrion )

Mitochondria (singular: mitochondrion): 

Mitochondria (singular: mitochondrion ) Aerobic respiration takes place here Aerobic = oxygen is present/required Food substances such as glucose are oxidized here to release energy  fuels cellular activities such as growth , repair and cell division .

Rough Endoplasmic Reticulum (RER): 

Rough Endoplasmic Reticulum (RER)

Rough ER: 

Rough ER Endo = within plasmic/plasma = cytoplasm reticulum = network. numerous ribosomes attached membrane is continuous with the nuclear envelope Ribosomes are made of RNA needed to synthesize proteins If ribosomes are attached to the RER, they make proteins that are usually transported out of the cell (via Golgi body )  “secretion” free ribosomes in the cytosol make proteins that are used within the cell.

Smooth ER: 

Smooth ER

Smooth ER: 

Smooth ER continuous with RER. More tubular synthesize lipids and steroids (such as sex hormones ) and detoxify harmful substances. Abundant in …?

Golgi body: 

Golgi body

Golgi body: 

Golgi body

Golgi body (aka Golgi apparatus): 

Golgi body (aka Golgi apparatus) a stack of flattened discs with vesicles merging into or buddings off the sides. r eceives, modifies and sorts substances ( mainly proteins) made by the ER , and package these substances in vesicles for secretion out of the cell or for use inside the cell. Transport of lipids around the cell Creation of lysosomes

Vacuole : 

Vacuole

Vacuole : 

Vacuole bound by a single membrane and filled with fluids. main function: store substances. In plant cells, there is usually only one, large, central vacuole filled with cell sap , which has dissolved substances such as sugars, mineral salts and amino acids stored. This large vacuole is bound by tonoplast . In animal cells, vacuoles still contain water and food substances, but are smaller and more temporary.

Cellulose cell wall: 

Cellulose cell wall

Cellulose cell wall: 

Cellulose cell wall on the outside of the cell membrane Fully permeable (meaning all dissolved substances can pass freely gives the plant mechanical support and its rigid shape prevents plant cells from bursting and collapsing .

Chloroplasts: 

Chloroplasts

Chloroplast : 

Chloroplast double membrane-bound Contains green pigment chlorophyll which captures light energy to make glucose and oxygen during photosynthesis.

Lysosomes: 

Lysosomes Produced by Golgi body Vesicles containing hydrolytic enzymes Digest material engulfed by cell Digest and recycle materials from damaged organelles

Exercise time!: 

Exercise time!

PowerPoint Presentation: 

Cell wall Cell membrane Chloroplast Mitochondrion Nucleus Rough endoplasmic reticulum ribosomes Vacuole Tonoplast Golgi body Cytoplasm Lysosome

Common mistakes in drawing: 

Common mistakes in drawing READ the requirements: many parts and details are NOT visible under light microscope! jagged lines not done in pencil wrong proportion no title

My annotations: 

My annotations sp : spelling exp : expression star : accurate and fits the requirement of the task flower : nicely drawn, but NOT according to instruction (e.g. shown too much detail) Redo : attach redone work to the back of original and re-submit on the same day ^ means missing keywords or elaboration

Typical Animal cell vs. typical plant cell: 

50 Chapter 5 Typical Animal cell vs. typical plant cell Nucleus Golgi apparatus Mitochondria Endoplasmic Reticulum Centrioles Chloroplasts

Typical Animal cell vs. typical plant cell: 

51 Chapter 5 Typical Animal cell vs. typical plant cell Nucleolus Ribosomes Central Vacuole Smooth E.R. Cell Wall

Specialized Cells—relating structure to function: 

Specialized Cells—relating structure to function

Specialized cells: relating structure to function: 

Specialized cells: relating structure to function All cells come from undifferentiated stem cells, which divide into new cells and differentiate to acquire , modify or lose structural features in order to perform specific functions .

Red blood cells: 

Red blood cells

Red blood cells: 

Red blood cells Structural feature: Contains a red pigment molecule called haemoglobin Function: haemoglobin can bind with oxygen in the lungs and transport it to all parts of the body.

Red blood cells: 

Red blood cells Structural feature: Mature (mammalian) red blood cells has no nucleus

Red blood cells: 

Red blood cells Function: More space to carry haemoglogin, hence more capacity to carry oxygen .

Red blood cells: 

Red blood cells Structural feature: Biconcave disc shape Function: Increased surface area to volume ratio , hence increased rate of oxygen diffusion in and out of the cell.

Red blood cell: 

Red blood cell Structural feature: flexible Function: Able to change shape and pass through narrow capillaries

Xylem vessel: 

Xylem vessel Structural feature: No cross-walls or protoplasm in the stacked up xylem cells Function: Forms long, hollow tubes with continuous lumen , through which water and dissolved minerals flow up from roots to leaves and stems through without obstruction.

Xylem vessel: 

Xylem vessel Structural feature: Has lignin deposits on the cellulose cell wall Function: Lignin strengthen the walls, prevent the vessel from collapsing provides mechanical support to the plant.

Xylem vessel: 

Xylem vessel Structural feature: Lignin is hydrophobic (meaning repels water) Function: Prevent water leakage into the cellulose cell wall, thus ensure efficient conduction of water.

Root hair cell: 

Root hair cell Structural feature: Long and narrow extension Function: Increased surface area to volume ratio  increased rate of uptake of water and dissolved minerals from the soil.

Organization in Multicellular Organisms: 

Organization in Multicellular Organisms Tissues Organs Organ System Organism Cells

Tissue : 

Tissue A tissue is a group of cells, not necessarily identical, that together carry out a specific function . Simple tissue: formed from cells of the same type Complex tissue: contains more than one cell type (but all from the same origin)

Organ : 

Organ An organ is a structure formed by multiple tissues joined in a structural unit to perform a specific function together .

Organ system: 

Organ system An organ system is made up by two or more organs working together to perform a specific function.

Homework: 

Homework 1. On a sheet of blank paper, draw a 2-D diagram of a typical animal cell and a diagram of a typical plant cell (one diagram on each half of the paper), showing ONLY structures visible under the light microscope. Special attention to: - accuracy/proportion - neat/sharpness - labeling 2. Draw analogy of parts of a typical cell (animal AND plant) to a city (real or in virtual/gaming world). You can do it in writing, or use other creative ways. Explain your analogy. Example: "The mitochondria are like powerplants, because they release the chemical energy in the glucose to power cell activities, just like powerplants release chemical energy in the fossil fuel to provide power for the functioning of the city."