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Bio Chapter 7 - Cell Functions

Lesson 7.1 - Intro To Cellular Life

Study - New Technology allowed people to study the movement and structure of cells

Microscopes:

  • Electron microscopes reveal details 1000 times bigger than visible in light microscopes

  • Transmission electron microscopes are used to show cell structure and large protein molecules. Electrons go through and need to be cut into slices

  • Scanning electron microscopes create 3D images. Electrons bounce off of and do not have to be cut into small slices

Prokaryotes + Eukaryotes:

  • Types of Cells Include:

    • Bacteria, plants, animals, fungi, protists

  • All Cells Include:

    • Cell Membrane

    • Cytoplasm

    • Ribosomes

    • DNA

  • Prokaryotes:

    • Genetic material not contained

    • No membrane-bound organelles

    • Smaller than eukaryotic cells

    • Bacteria

  • Eukaryotes:

    • DNA is stored in the nucleus

    • Long and complex

    • Contain dozens of structures and internal membranes

    • Highly specialized

    • Plants, animals, fungi, protists

  • Discovery of Cells

    • James Hooke coined the term “cell”

    • He was attempting to study cork

    • Antonie Van Leeuwenhoek observed microorganisms in pond water under a microscope

    • Matthias Scheider concluded that all plant tissue is made of cells and that cells are a basic unit of life

    • Theodore Schwann concluded that all animal tissue is made of cells

  • Properties of Cells/Cell Theory

    • All organisms consist of 1 or more cells

    • Cells are the basic unit of life and structure of all organisms

    • All cells come from preexisting cells

Lesson 7.2 - Eukaryotic Cell Structure

  • Eukaryotic Cell Structures:

    • Organelles: Preform cell functions

    • 2 Parts: Nucleus + Cytoplasm

    • Cytoplasm is outside the nucleus

  • Plant Cell:

Plant Cell Diagram:

  • Animal Cell:

Animal Cell Diagram

  • Endomembrane System:

    • Nucleus - Holds instructions

    • Ribosomes - Build

    • ER - Shape

    • Golgi - Modify/Sort/Package

    • Vesicles - Ships

  • Nucleus:

    • Control center

    • Holds instructions for making proteins

    • Surrounded by 2 nuclear envelopes

    • Envelopes contain pores that only RNA can pass through

    • Granular material in the nucleus - Chromatin

    • Chromatin - made of RNA and protein

    • When a cell divides, chromatin condenses to become chromosomes. These contain genetic info

    • The nucleolus only holds info to make more ribosomes

  • Ribosomes:

    • Small particles of RNA and protein found freely throughout the cytoplasm

    • Create proteins in “Protein Synthesis

      • Follow instructions from the nucleus and RNA

  • ER:

    • Rough ER (Part of protein synthesis) + Smooth ER (Not part of protein synthesis)

    • Ribsomones on Rough ER are found on the surface

    • Rough ER - Proteins are assembled on ribosomes

    • Smooth ER- Creates lipids and detoxifies drugs

  • Golgi Apparatus:

    • Proteins are moved from ER to Golgi

    • Modifies, Sorts, and Packages proteins

    • Sends to vesicles which send to their necessary location

  • Making Proteins:

  1. Nucleus

  2. Nuclear Pore

  3. Ribosome

  4. Protein

  5. Rough ER

  6. Golgi Body

  7. Vesicle

  8. Cell Membrane + to a new location

  • Lysosomes:

    • Small organelles filled with enzymes

    • Break down lipids, carbs, and proteins into things that can be used by the rest of the cell

    • Breaks down organelles that no longer have a use

    • “Trash/Recycle”

  • Vacuoles:

    • Saclike structures

    • Store water, salts, proteins, and carbs

    • Holds pigments + toxins as defense mechanisms

    • In plant cells - the central vacuole is filled with liquid that is used for photosynthesis + helps the plant stand upright

    • Unicellular Organisms - filled with water and have a pump to help from exploding

  • Mitochondria:

    • Convert energy from food into compounds that can be used more conveniently by the rest of the cell

    • Enclosed by 2 membranes

    • More folds = more surface area = more energy = more ATP

  • Choloplasts:

    • Capture energy from the sun and convert it into chemical energy

    • Photosynthesis

    • Surronded by 2 membranes

    • Contain chlorophyll

  • Cytoskeleton:

    • Gives eukaryotic cells their shape

    • A network of protein filaments

    • Also involved in cell movement

  • Microfilaments:

    • Thread-like structures made of the protein actin

    • Make extensive networks in cells

    • Make a tough, flexible framework that supports the cell

    • Helps move cells

  • Microtubules:

    • Hollow structures that are made up of the protein tubulins

    • Help maintain cell shape

    • Helps cells divide (mitosis+meosis)

    • Build projections from the cell surface that enable cells to swim rapidly through liquids

    • Centrioles are also formed from tubulins

    • These are located near the nucleus and help organize cell division

Lesson 7.3 - Cell Boundaries

  • All cells have a thin, flexible barrier known as the cell membrane

  • Plants, fungi, bacteria + some protist cells also produce a stronger layer known as a cell wall

    • The main function of the cell wall is to provide support and protection for the cell

    • No movement - extra padding

    • Also attacks bacteria

    • Lies outside the cell membrane

    • Porous enough to allow water, oxygen, carbon dioxide, and other substances to easily pass through

  • Cell Membrane

    • Regulates what enters and exits the cell

    • Provides support and protection for the cell

Diagram of a Cell Membrane

  • The composition of nearly all cell membranes is made of a double-layered sheet called a lipid bilayer

    • Gives a flexible structure that forms a barrier between a cell and its surroundings

    • Contains protein molecules embedded in the lipid bilayer, some of which have carb molecules attached to them

  • Diffusion Through Cell Boundaries

    • Every cell lives in a liquid environment

    • The cell membrane regulates the movement of diffusion from the liquid on one side of the membrane to another

    • Particles tend to move from areas of high concentration to low concentration

    • This is the process of diffusion

    • This will continue until a state of equilibrium is reached

Process of Diffusion Through Cell Membranes

  • Passive Transport

    • Depends upon random particle movements

    • Substances diffuse across membranes without using energy

    • This is called passive transport

  • Osmosis

    • Diffusion of water through a selectively permeable membrane

    • Water - solvent - what is doing the dissolving

How Osmosis Works

  • Levels of Concentration

    • Water diffuses from areas of high to low concentration

    • More concentrated solution - Hypertonic

    • Area of high concentration

      • Water with more sugar present

    • Less concentrated solution - Hypotonic

    • Area of low concentration

      • Water with less sugar present

    • Water with equal parts sugar and water

      • Isotonic

    • Osmosis is only concerned with water and its’ levels

    • Particles never stop moving, as they must always work to maintain homeostasis

  • Osmotic Pressure

    • Occurs when water on the hypertonic side puts pressure on the membrane

    • The cell is almost always hypertonic to fresh water

    • If a cell has too much water, it is at risk of exploding or bursting (which leads to the death of the cell)

    • Cells in large organisms and with cell walls are much less likely to burst

  • Facilitated Diffusion

    • Membranes contain integral proteins that can assist in the movement of larger particles

    • The use of these proteins is called facilitated diffusion

    • Protein channels are specific to certain particles only

    • Ex. Glucose Transport - Only for glucose

    • Fast and Specific

    • Still considered diffusion

    • Only occurs from high to low concentration

  • Active Diffusion

    • Occurs when materials have to move from areas of low to high concentration

    • Against the concentration difference

    • Requires energy

      • Ex. Stuffing things into a closet

  • Molecular Transport

    • Small molecules are carried by proteins

    • Allows movement from low to high

    • Requires energy

  • Large Particle Transport

    • Occurs when particles are too large to be carried by proteins

    • Active transport

  • Endocytosis

    • Process of taking material into the cell by means of pockets of the cell membrane

    • A vacuole is formed around the material that works to bring it into the cell

    • This vacuole is from the cell membrane

  • Phagocytosis

    • The process of cytoplasm surrounding food

    • This is then engulfed by the cell

    • Requires energy

      • Collect

      • Pinch Off

      • Turns to Vesicle

      • Engulfed by Cell

  • Pinocytosis

    • The process of cytoplasm surrounding waste

    • This is then removed from the cell

    • Requires energy

      • Collect

      • Pinch Off

      • Turns to Vesicle

      • Released

  • Exocytosis

    • The release of waste from a cell

    • Cell membrane fuses with waste from inside the cell

    • Then removes it from the cell

    • Requires energy

Lesson 7.4 - Diversity of Cellular Life

  • Unicellular Organisms

    • Made of only 1 cell

    • Dominate life on Earth because so many of them can fit per any given space compared to multi

    • Includes: All bacteria cells, certain eukaryotic organisms (yeast + amebas)

  • Multicellular Organisms

    • Made of many cells

    • Great variety in these cells

    • Includes: All plant cells, all animal cells, most fungus cells, some protist cells

  • Specialized Animal Cells

    • Red blood cells transport oxygen

    • Cells in the pancreas produce a protein (endomembrane systems)

    • Muscle cells allow for movement

  • Specialized Plant Cells

    • Exchange carbon dioxide, oxygen, water vapor, and other gases through stomata

    • Guard cells surround the stomata and regulate the exchanges

  • Levels of Organization

    • Individual Cells - 1st level of organization

    • Tissues - Cells are grouped and create these

      • A group of similar cells that perform a particular function

    • Organ

    • Organ Systems

    • Organism

    • Ex. Muscle cell > Smooth muscle tissue > Stomach > Digestive System

  • Types of Tissue (Animals)

    • Muscle - Moves

    • Skin - Epithelial

    • Nervous - Neurons

    • Connective - Ligaments/Cartlidge

  • Organs (Animals)

    • Groups of tissues that work together to perform a specific function

    • Completes a series of specialized tasks

    • Work together to create organ systems

      • Nervous System

      • Circulatory System

      • Skeletal System

      • Digestive System

Lesson 7.1 - Intro To Cellular Life

Study - New Technology allowed people to study the movement and structure of cells

Microscopes:

  • Electron microscopes reveal details 1000 times bigger than visible in light microscopes

  • Transmission electron microscopes are used to show cell structure and large protein molecules. Electrons go through and need to be cut into slices

  • Scanning electron microscopes create 3D images. Electrons bounce off of and do not have to be cut into small slices

Prokaryotes + Eukaryotes:

  • Types of Cells Include:

    • Bacteria, plants, animals, fungi, protists

  • All Cells Include:

    • Cell Membrane

    • Cytoplasm

    • Ribosomes

    • DNA

  • Prokaryotes:

    • Genetic material not contained

    • No membrane-bound organelles

    • Smaller than eukaryotic cells

    • Bacteria

  • Eukaryotes:

    • DNA is stored in the nucleus

    • Long and complex

    • Contain dozens of structures and internal membranes

    • Highly specialized

    • Plants, animals, fungi, protists

  • Discovery of Cells

    • James Hooke coined the term “cell”

    • He was attempting to study cork

    • Antonie Van Leeuwenhoek observed microorganisms in pond water under a microscope

    • Matthias Scheider concluded that all plant tissue is made of cells and that cells are a basic unit of life

    • Theodore Schwann concluded that all animal tissue is made of cells

  • Properties of Cells/Cell Theory

    • All organisms consist of 1 or more cells

    • Cells are the basic unit of life and structure of all organisms

    • All cells come from preexisting cells

Lesson 7.2 - Eukaryotic Cell Structure

  • Eukaryotic Cell Structures:

    • Organelles: Preform cell functions

    • 2 Parts: Nucleus + Cytoplasm

    • Cytoplasm is outside the nucleus

  • Plant Cell:

Plant Cell Diagram:

  • Animal Cell:

Animal Cell Diagram

  • Endomembrane System:

    • Nucleus - Holds instructions

    • Ribosomes - Build

    • ER - Shape

    • Golgi - Modify/Sort/Package

    • Vesicles - Ships

  • Nucleus:

    • Control center

    • Holds instructions for making proteins

    • Surrounded by 2 nuclear envelopes

    • Envelopes contain pores that only RNA can pass through

    • Granular material in the nucleus - Chromatin

    • Chromatin - made of RNA and protein

    • When a cell divides, chromatin condenses to become chromosomes. These contain genetic info

    • The nucleolus only holds info to make more ribosomes

  • Ribosomes:

    • Small particles of RNA and protein found freely throughout the cytoplasm

    • Create proteins in “Protein Synthesis

      • Follow instructions from the nucleus and RNA

  • ER:

    • Rough ER (Part of protein synthesis) + Smooth ER (Not part of protein synthesis)

    • Ribsomones on Rough ER are found on the surface

    • Rough ER - Proteins are assembled on ribosomes

    • Smooth ER- Creates lipids and detoxifies drugs

  • Golgi Apparatus:

    • Proteins are moved from ER to Golgi

    • Modifies, Sorts, and Packages proteins

    • Sends to vesicles which send to their necessary location

  • Making Proteins:

  1. Nucleus

  2. Nuclear Pore

  3. Ribosome

  4. Protein

  5. Rough ER

  6. Golgi Body

  7. Vesicle

  8. Cell Membrane + to a new location

  • Lysosomes:

    • Small organelles filled with enzymes

    • Break down lipids, carbs, and proteins into things that can be used by the rest of the cell

    • Breaks down organelles that no longer have a use

    • “Trash/Recycle”

  • Vacuoles:

    • Saclike structures

    • Store water, salts, proteins, and carbs

    • Holds pigments + toxins as defense mechanisms

    • In plant cells - the central vacuole is filled with liquid that is used for photosynthesis + helps the plant stand upright

    • Unicellular Organisms - filled with water and have a pump to help from exploding

  • Mitochondria:

    • Convert energy from food into compounds that can be used more conveniently by the rest of the cell

    • Enclosed by 2 membranes

    • More folds = more surface area = more energy = more ATP

  • Choloplasts:

    • Capture energy from the sun and convert it into chemical energy

    • Photosynthesis

    • Surronded by 2 membranes

    • Contain chlorophyll

  • Cytoskeleton:

    • Gives eukaryotic cells their shape

    • A network of protein filaments

    • Also involved in cell movement

  • Microfilaments:

    • Thread-like structures made of the protein actin

    • Make extensive networks in cells

    • Make a tough, flexible framework that supports the cell

    • Helps move cells

  • Microtubules:

    • Hollow structures that are made up of the protein tubulins

    • Help maintain cell shape

    • Helps cells divide (mitosis+meosis)

    • Build projections from the cell surface that enable cells to swim rapidly through liquids

    • Centrioles are also formed from tubulins

    • These are located near the nucleus and help organize cell division

Lesson 7.3 - Cell Boundaries

  • All cells have a thin, flexible barrier known as the cell membrane

  • Plants, fungi, bacteria + some protist cells also produce a stronger layer known as a cell wall

    • The main function of the cell wall is to provide support and protection for the cell

    • No movement - extra padding

    • Also attacks bacteria

    • Lies outside the cell membrane

    • Porous enough to allow water, oxygen, carbon dioxide, and other substances to easily pass through

  • Cell Membrane

    • Regulates what enters and exits the cell

    • Provides support and protection for the cell

Diagram of a Cell Membrane

  • The composition of nearly all cell membranes is made of a double-layered sheet called a lipid bilayer

    • Gives a flexible structure that forms a barrier between a cell and its surroundings

    • Contains protein molecules embedded in the lipid bilayer, some of which have carb molecules attached to them

  • Diffusion Through Cell Boundaries

    • Every cell lives in a liquid environment

    • The cell membrane regulates the movement of diffusion from the liquid on one side of the membrane to another

    • Particles tend to move from areas of high concentration to low concentration

    • This is the process of diffusion

    • This will continue until a state of equilibrium is reached

Process of Diffusion Through Cell Membranes

  • Passive Transport

    • Depends upon random particle movements

    • Substances diffuse across membranes without using energy

    • This is called passive transport

  • Osmosis

    • Diffusion of water through a selectively permeable membrane

    • Water - solvent - what is doing the dissolving

How Osmosis Works

  • Levels of Concentration

    • Water diffuses from areas of high to low concentration

    • More concentrated solution - Hypertonic

    • Area of high concentration

      • Water with more sugar present

    • Less concentrated solution - Hypotonic

    • Area of low concentration

      • Water with less sugar present

    • Water with equal parts sugar and water

      • Isotonic

    • Osmosis is only concerned with water and its’ levels

    • Particles never stop moving, as they must always work to maintain homeostasis

  • Osmotic Pressure

    • Occurs when water on the hypertonic side puts pressure on the membrane

    • The cell is almost always hypertonic to fresh water

    • If a cell has too much water, it is at risk of exploding or bursting (which leads to the death of the cell)

    • Cells in large organisms and with cell walls are much less likely to burst

  • Facilitated Diffusion

    • Membranes contain integral proteins that can assist in the movement of larger particles

    • The use of these proteins is called facilitated diffusion

    • Protein channels are specific to certain particles only

    • Ex. Glucose Transport - Only for glucose

    • Fast and Specific

    • Still considered diffusion

    • Only occurs from high to low concentration

  • Active Diffusion

    • Occurs when materials have to move from areas of low to high concentration

    • Against the concentration difference

    • Requires energy

      • Ex. Stuffing things into a closet

  • Molecular Transport

    • Small molecules are carried by proteins

    • Allows movement from low to high

    • Requires energy

  • Large Particle Transport

    • Occurs when particles are too large to be carried by proteins

    • Active transport

  • Endocytosis

    • Process of taking material into the cell by means of pockets of the cell membrane

    • A vacuole is formed around the material that works to bring it into the cell

    • This vacuole is from the cell membrane

  • Phagocytosis

    • The process of cytoplasm surrounding food

    • This is then engulfed by the cell

    • Requires energy

      • Collect

      • Pinch Off

      • Turns to Vesicle

      • Engulfed by Cell

  • Pinocytosis

    • The process of cytoplasm surrounding waste

    • This is then removed from the cell

    • Requires energy

      • Collect

      • Pinch Off

      • Turns to Vesicle

      • Released

  • Exocytosis

    • The release of waste from a cell

    • Cell membrane fuses with waste from inside the cell

    • Then removes it from the cell

    • Requires energy

Lesson 7.4 - Diversity of Cellular Life

  • Unicellular Organisms

    • Made of only 1 cell

    • Dominate life on Earth because so many of them can fit per any given space compared to multi

    • Includes: All bacteria cells, certain eukaryotic organisms (yeast + amebas)

  • Multicellular Organisms

    • Made of many cells

    • Great variety in these cells

    • Includes: All plant cells, all animal cells, most fungus cells, some protist cells

  • Specialized Animal Cells

    • Red blood cells transport oxygen

    • Cells in the pancreas produce a protein (endomembrane systems)

    • Muscle cells allow for movement

  • Specialized Plant Cells

    • Exchange carbon dioxide, oxygen, water vapor, and other gases through stomata

    • Guard cells surround the stomata and regulate the exchanges

  • Levels of Organization

    • Individual Cells - 1st level of organization

    • Tissues - Cells are grouped and create these

      • A group of similar cells that perform a particular function

    • Organ

    • Organ Systems

    • Organism

    • Ex. Muscle cell > Smooth muscle tissue > Stomach > Digestive System

  • Types of Tissue (Animals)

    • Muscle - Moves

    • Skin - Epithelial

    • Nervous - Neurons

    • Connective - Ligaments/Cartlidge

  • Organs (Animals)

    • Groups of tissues that work together to perform a specific function

    • Completes a series of specialized tasks

    • Work together to create organ systems

      • Nervous System

      • Circulatory System

      • Skeletal System

      • Digestive System