Biology Lesson # 1 the Microscope

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Biology Lesson # 1 the Microscope

Biology Lesson # 1 – The Microscope

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Parts of the Compound Light Microscope  Since the invention of the microscope, scientists have been able to analyze the function and individual parts within .  The microscope that we are using is called a microscope, which uses light focused through different lenses to form a magnified of a specimen or object.

Part Function

Body Tube

Revolving Nosepiece

Objective Lenses

Stage

Diaphragm

Lamp

Base

Fine Adjustment Knob

Coarse Adjustment Knob

Stage Clips

Arm

Ocular Lens (Eyepiece) Magnification  A microscope can have a magnification up to (it could produce an image 20 times larger than the actual object).  A microscope contains magnification lenses (the and lens), which when used together, allows for a larger magnification. o For example, if the ocular lens is 10x magnification, and the highest objective lens is 40x magnification, then the total magnification is magnification of the image!

Resolution  We can magnify an image all we want, but if the original image details are , we won’t be able to see much more when it is bigger.  The resolution, or resolving power, is the .

Contrast  Contrast is the .  Scientists often use to improve the contrast of the structures they are observing under the microscope. The most common stains are methylene blue and iodine. Sometimes scientists even use dyes and then place the objects under ultraviolet (UV) light.

Electron Microscope  An electron microscope uses a instead of , and is much more powerful than a compound microscope. Some images can be magnified 1 500 000x!  The downside to electron microscopes is that a beam of electrons can pass only through thin slices of a sample, so only can be studied, which means that living cells (which are thicker) cannot be studied, only ones that are dead. Biology Lesson # 2 – Animal & Plant Cells

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The Cell  Cytology – the branch of biology that . It is made possible by the .  Robert Hooke first used the word “cell” in 1663. o He was examining under a microscope, and thought that cork had many compartments or “cells” throughout its entirety. o He originally thought that cells were for the , but we now know today that many other things occur within cells.  Anton van Leeuwenhoek studied simple living organisms, and thought them to be little living molecules, called “ ”  Cell theory states that: 1. . 2. . 3. .  Each cell contains smaller parts called organelles, which have special functions that maintain all the life processes of the cell, including: o o o o o o o Cell Organelles

Cell Part Function Cell  A around the cell Membrane  This membrane allows different substances to move in and out of the cell, which is called . The amount of diffusion depends on the concentration of the particles on both sides of the membrane. Particles will always diffuse from . Cytoplasm  A that fills the cell and surrounds the organelles, where they can stay in place or move around.  It contains the required by the cell to carry on its life processes. Nucleus  The of the cell (like the brain). It controls all the activities in the cell, including and .  The nucleus is surrounded by the , which allows pores to transport materials in and out of the nucleus itself.  The most dense area of the nucleus is called the .  The nucleus contains the cell’s DNA ( ), which is bound to proteins called . Centrioles  Only found in cells.  Structures responsible for . Vacuoles  Membrane-bound organelles that used in the cell. Vesicles  Membrane-bound organelle that throughout the cell. Mitochondria  The of the cell – chemical reactions occur to convert in sugar into energy that the cell can use. Lysosomes  Small organelles that are filled with (proteins that speed up chemical reactions) where takes place.  They also break down invading bacteria and damaged cell organelles – the in the cell. Ribosomes  Small organelles where . Endoplasmic  A series of interconnected small tubes that Reticulum throughout the cell (ER)  ER is associated with , and have ribosomes attached to it.  ER is associated with making . Golgi  Receives proteins from the ER, and Apparatus for delivery throughout the cell or even outside the cell. Cytoskeleton  Internal network of fibres, made of proteins, which helps . Cell Wall  Only found in cells.  A rigid frame around the cell that provides . Chloroplasts  Only found in cells.  Contain a green substance called , which uses energy from the sun to convert carbon dioxide and water into sugar and oxygen in a process called .

Differences between Animal and Plant Cells  Only plant cells and .  Plants have a compared to animal cells.  Some plant cells store energy in the form of , whereas animal cells store energy in the form of .  Some animal cells have specialized functions, such as .  Animal cells have which are involved in cell division, whereas plant cells do not. Plant Cell Diagram

Animal Cell Diagram Biology Lesson # 3 – The Life of Cells Name: Date:

The Cell Cycle  Cells reproduce through a continuous sequence of growth and division called cell cycles.  The cell cycle differs in based on the different types of cells.  The cell cycle has main stages:

A.  This cell growth is also called , and is divided into three parts o

o

o

B.  This division is also called , and is the division of

 , the division of the cytoplasm and organelles, also occurs in this stage.

A Closer Look at Interphase  In this stage, .  DNA is in the form of (thin strands which are hard to see).  Centrioles and DNA are replicated at this time – each .

A Closer Look at Mitosis  Mitosis is cell division – the chromosomes and nucleus of the “parent” cell are to produce two identical “daughter” cells.  The three main functions of mitosis are: o - we need to increase our cellular amount to increase in size o - to replace worn or old cells o - sperm and egg cells go through a special type of division called to create new life.  There are stages of mitosis. Use the acronym to remember the order. Stage 1 –  In this stage, (also called poles) of the cell  appear around the centrioles  The chromatin condenses ( ) into and are now visible.  The chromosomes pair up to form a double strand. Where the strands join together is called the .  The nuclear membrane and nucleolus and disappear

Stage 2 –  At this stage, the chromosomes of the cell (called the ).  Centrioles are now at the with spindle fibres running between them  Each double-stranded chromosome is also attached to a spindle fibre at the centromere.

Stage 3 –  At this stage, the chromosome pair is at the centromere, with one going to one pole, and the other going to the other pole (opposite ends of the cell).  The chromosomes are now single stranded, and are now called .

Stage 4 –  In this stage, the  The spindle fibre breaks down and disappears  The nuclear membrane starts to around the chromatids and the nucleolus reappears  The chromatids uncoil (thin) and again.

Cytokinesis  This occurs at the , and involves the , including organelles.  In animal cells, the cell membrane pinches in, forming a “ ” where it will eventually split in two.  In plant cells, a new cell wall forms between the two halves called a “ ”

Interphase (again!)  Once the division is done, the new cells are called “ ” cells  The daughter cells are to each other and to their original parent cell  Each daughter cell enters a before they will also divide in mitosis. Biology Lesson # 4 – The Death of Cells & Cancer

Rates of Cell Growth and Division  The of cells and varies depending on the of cell. o For example, do not undergo mitosis once they mature (which is why nerve damage is almost always ). o , on the other hand, divide regularly, which is why cuts and scrapes heal rather quickly.  organisms undergo rapid mitosis of cells in the areas of growth, whereas mitosis is much slower in organisms.  If cells are more likely to be as they function, they tend to divide faster as well. o divide fast since exposed to many chemicals during digestion. o , on the other hand, last up to four months, because they are less likely to be damaged.  In plants, more division and growth occurs in the meristem region (the ) compared to the .

Environmental Factors that Affect Mitosis  The might also play a role in the rate of cell division.  If your environment changes, mitosis will occur more rapidly in some areas of your body. For example, your blood cells would divide more rapidly in areas of , because they receive .  In plants, the rate of mitosis changes from .  The stem cells of plants grow more rapidly when facing away from the light, which is why plant stems the light (the opposite side is now heavier with more cells).  decrease the rates of mitosis in certain cells to stop from growing and spreading. Other drugs stop the to stop a certain cell from functioning.

Cell Death  The life of cells is determined by the cell cycle, but some cells die because they suffer throughout their period of growth or division. o For example – exposure to . o Cell death from damage is called .  Cells can also die when they can no longer or are . o For example – cells used to fight a viral infection. When the infection is gone, they are no longer necessary. o This regular death of cells is called .

Cancer Cells  A cell that divides and is called a cell. These cells develop when a change occurs in the cell that affects how the cell .  If the DNA of the cell changes, it is called a . Some mutations occur due to: o - commonly linked to and

o - Ultraviolet (UV) radiation is commonly linked to cancer o - Cigarette smoke is commonly linked to cancer.  These factors are called .  A is a mass of cancer cells formed by abnormal rapid cell division, and there are two types: 1. o it is o remains in a o causes

2. o it is o can to other areas of the body o causes  and can be used to slow or stop the effects of dividing cancer cells. o The chemical treatment is called o The radiation treatment is called

Comparing Normal Cells with Cancer Cells

Normal Cells Cancer Cells Biology Lesson # 5 – Specialized Cells

Regeneration  is the process whereby a body part is or .  The best example of regeneration is the – it can regrow amputated limbs, tails, eye lenses, and even some parts of its heart!  This is very unique, and regeneration is in humans. o There are a few special cases, but only the is known to naturally regenerate. o There have been cases where have regrown if amputated. o There have also been cases where organs were regenerated in the lab, such as a functioning .

Specialized Cells  All cells come from pre-existing cells ( ), and all cells begin as a single cell (a ); this zygote then begins to divide and cells develop in different ways.  We are organisms – made up of of cells.  Not all of the cells are exactly the same – they do all have the information, but they all do jobs.  Cells develop in different ways to perform particular functions in a process called .  For example, animal cells may become specialized to form cells, or cells, and plant cells can specialize to form cells, cells, etc.

Stem Cells  Unspecialized cells in the body are called – this is the very first cell we came from.  Scientists believe that stem cells may be used to treat or by regenerating organs, since they are able to become in the human body.  There are two types of stem cells: 1. stem cells – found in embryos o Many stem cells before birth 2. stem cells – found in mature organisms o Few stem cells after birth  Stem cells are also found in plants, and they are called cells. They are found in the root tip and stems Biology Lesson # 6 – Plants – Tissues, Organs & Systems

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Definitions  – specialized cells that group together to perform their tasks  – is an organized group of tissues that performs a special function.  – groups of organs that work together to perform a large body task  – a group of organ systems making up an entire living being.

Plant Tissues  There are types of tissues found in plants.

Tissue Type Description

1. Meristematic  Made of cells (stem cells) found Tissue the plant  Responsible for growing of the plant.

2. Epidermal  Forms a on the leaf Tissue which is clear and very thin  Contain tiny openings called , that allows carbon dioxide, water vapour, and oxygen into or out of the leaf easily. Most are found on the to minimize .

3. Ground  These tissues make up the of the plant, and there Tissue function depends on where it is located - In the stem – provides - In the roots – stores - In the leaves – where occurs

4. Vascular  Transports up and down the plant. Tissue - - movement of water and minerals from the to the leaves for photosynthesis – can only move . - - transports sugar produced in photosynthesis from the to use as energy – can move both . Plant Organs  There are main organs in most flowering plants:

1. The Roots  the plant in the soil and allows the plant to grow above the soil without toppling over – provides .  Collect from soil and transport it to them stem and store made in other parts of the plant.

2. The Leaf  Accomplish – a chemical reaction in which carbon dioxide and water are converted into sugar and oxygen   Ground tissue called is where the chemical reaction of photosynthesis actually takes place in the leaf.

3. The Stem  Transports throughout the plant through vascular tissue (xylem and phloem)  Supports the

4. The Flower or Fruit  The structure of the plant – produces seeds through sexual reproduction. The is the male part of the plant, and the inside are the female part.  When the pollen and egg unite, a fertilized egg becomes a . Some seeds are surrounded by a flesh called the , others are simply encased in a hard .

Plant Organ Systems  Plant organ systems are much less than animal organ systems.  There are organ systems in plants: o The – everything the ground. o The – everything the ground.  Organ systems working together: o When daylight hours , specialized cells record the changes and deliver chemical messages to the tissues to . o Another example is when there is a lack of water or excessive heat, where chemical messages are sent to which is where the most water loss occurs. Biology Lesson # 7 – Animals – Tissues, Organs & Systems

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Animal Tissues  There are types of tissues in animals. Type of Tissue Description & Function Epithelial Tissue  Cells tightly packed together to form a .  Lines body cavities and surfaces, and forms that produce hormones, enzymes, and sweat. Connective Tissue  Cells used to other tissues together (such as tendons, ligaments, and cartilage), forms , and fills

Muscle Tissue  Three types that including - (moving limbs – voluntary movement) - (blood vessels and organs – involuntary movement) - (the heart – involuntary movement) Nervous Tissue  Nerve cells which create messages, called , and transmit them throughout the body.  Nerve cells can also receive messages from the body

Animal Organ Systems

1. The Respiratory System  The main function of this system is – and .  Air enters the mouth or nose and travels through the (windpipe), to the lungs (big tubes called to smaller ones called ), and into smaller thin sacs called .  Alveoli are surrounded by thin blood vessels called that allow to enter the capillaries into the blood to travel throughout the body, and allow to travel from the capillaries back to the alveoli.  Some organisms have only lung one, but humans have that sit in a cavity in the chest area  Lungs are coated with two sacs of connective tissue separated by a thin layer of which as the lungs move 2. The Circulatory System  The main function of this system is to throughout the body.  are thick-walled vessels that carry blood from the heart, with a that pushes the blood along  carry blood to the heart, and are thinner and in pressure.  connect the veins and arteries, and are the blood vessels – about one cell thick. o and flow in and out of capillaries by diffusion – oxygen moves in when the cells need it, and carbon dioxide and wastes are removed from cells. o The respiratory system and circulatory system always .  The average heart beats about times in a lifetime  The heart is divided into chambers: two , and two .  The heart is a (cardiac muscle tissue) that supplies blood to all parts of the body, including the lungs and the heart itself.  Blood contains (liquid), (carry oxygen), (protect the body from bacteria and viruses), and (help with blood clotting).

3. The Digestive System  The main function of this system is to throughout the body.  Food Passage:

 The mouth is covered in that secrete mucus, saliva, and enzymes  The tongue along with the teeth starts digestion. o The esophagus is a tube of where food travels down from the mouth  The stomach churns food and mixes it with digestive juices (strong acids) and enzymes – where digestion begins.  Digestive nutrients and waste move into the small and large intestines. are absorbed in the small intestine, and is absorbed in the large intestine.  are then stored in the rectum and exit the body through the anus

4. The Excretory System  The main function of this system is to and maintain the (salts) in the body.  When blood flows through the , wastes (urea, carbon dioxide, water) are removed and all these wastes form a fluid called .  Urine moves from the kidney to the urinary , where it is stored until it can be eliminated through the and out of the body.  can also be considered a part of the excretory system, because it also excretes wastes like water and salts in sweat.

5. The Integumentary System  The most organ system – made up mainly of and accessory structures (such as horns, antlers, hooves, quills, claws, hair, and nails, depending on the organism).  Also made up of - skin glands include (water and body salts) to cool the body, and that produce oil that lubricates, waterproofs, and prevents skin infections.  Skin is the in your body, which inner cells from damage and acts as a . It also Insulates and releases when necessary and excretes bodily through sweat  Skin Layers o - outer protective layer – thin epithelial tissue which prevents bacteria and viruses from entering, and makes vitamin D which is essential for bone development o - inner layer – including blood vessels, pores, fat, nerves, and muscle tissue. . blood vessels (get bigger) to release excess heat . Pores (made in sweat glands) . Fat provides . Nerves allow you to feel . Muscle tissue produces which prevent heat from being released. Biology Lesson # 8 – Body Systems & Health Name: Homeostasis  Body systems work together to maintain a steady state, called .  There is an acceptable range of in which body cells, tissues, and organs can operate efficiently.  To maintain this range, different organ systems must – they are interdependent because the action of one system contributes to the action of another system.  Example # 1 – when you get hot, your blood vessels . You also and keep your inside temperature steady. In this example, the and systems are being used.  Example # 2 – when you exercise, your muscles use oxygen and energy to keep you moving. Because of this, your so blood is pumped faster to your muscles, and your to provide the oxygen to the blood. In this example, the , , and systems are used.

Diagnosing Problems in Organ Systems  Since organ systems are interdependent, it is sometimes difficult to and medical problems.  A common physical examine includes: o Looking at your to check your surface organs. o Tapping of your to determine the size and density of your organs. o Using a stethoscope to listen to the determine if they are functioning properly. o A check to see if they are within normal ranges o Blood is taken to test red and white (which are chemicals that carry messages to regulate cells, tissues or organs). o Urine is taken to test for and overall health.

Medical Imaging Technologies  Diagnostic testing provides information about the structure and function of organs, tissues, and cells through .  In Canada, medical imaging is included as a part of our for necessary (not elective) procedures, but depending on your location in the country, there are sometimes for available appointments using these equipment, as they are very to maintain.  There are main medical imaging technologies:

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