Glencoe Life Structure and Function: Cell Structure and Function (copy)

Robert Hooke

English scientist that observed a piece of cork, and described the structure as "Cells"

Matthias Schleiden

German botanist who concluded that all plants are made of cells. Worked with Theodor Schwann

Rudolf Virchow

A German doctor who proposed that all cells come from preexisting cells.

Cell Theory

1- All living things are made of one or more cells. 2- The cell is the smallest unit of life.

3- All new cells come from preexisting cells

Macromolecules

Large molecules that are formed from smaller cells which perform specialized roles. Include nucleic acids, proteins, lipids, and carbohydrates.

What percentage of water takes up a cells volume?

70%

Water molecule areas

Positive and Negative: each attracts and attach to one another.

Nucleic Acids

Macromolecules that form when long chains of molecules called nucleotides join together. The order of nucleotides in DNA and RNA changes genetic information in a molecule.

DNA

Includes instructions for cell growth, reproduction, and processes that enable a cell to respond to its environment.

RNA

Used to make proteins and gives instructions to form them together; DNA creates RNA

Proteins

Long chains of amino acid molecules. They each have unique functions like transportation, communication, and breaking down substances.

Lipids

A large macromolecule that does not dissolve in water. Used for protective barriers in cells, like membranes. Also have roles in energy storage and communication.

Carbohydrates

Store energy, provide structural support, and are needed for communication between cells. Energy can be released quickly through chemical reactions.

Eukaryotes

Have a membrane-bound nucleus and membrane-bound organelles. Animals, plants, and protists are all eukaryotic.

Prokaryotes

Unicellular organisms like bacteria. Genetic material is not surrounded by a membrane. Instead, genetic material freely floats in cytoplasm. (no membrane bound organelles or nucleus)

Nucleus

A part of the cell containing DNA and RNA, responsible for growth and reproduction. Essentially the command center of the cell.

Organelles

Like organs for the cell, are special structures that perform vital functions necessary to the cell

Cell Membrane

A cell structure that controls which substances can enter or leave the cell. Provides protection and can be found in every cell.

What is a cell membrane made of?

Two types of macromolecules; proteins and a type of lipid called phospholipids.

Cell Wall

A rigid layer of nonliving material surrounds the cells of some plants and other organisms. Located outside the membrane. Protects the cell from viruses and other harmful organisms.

Cell Appendages

Used for cell movement.

Flagella

Whiplike tails found in one-celled organisms to aid in movement

Cilia

Hairlike projections that extend to help move the cell or other cells away from itself.

Cytoplasm

Made of water containing salts and other molecules. Makes up a large portion of the interior of a cell.

Cytoskeleton

A network of threadlike proteins that are joined together to form framework in a cell. Gives the cell its shape and helps it move.

Ribosomes

Makes proteins and is located in the cytoplasm. Can attach to endoplasmic reticulum (ER)

Endoplasmic Reticulum (ER)

An extensive membranous network in eukaryotic cells. Includes types of ribosome containing (rough) and ribosome-free (smooth) types.

Smooth ER

Makes lipids like cholesterol and helps remove harmful substances from a cell.

Rough ER

ER with ribosomes, and creates proteins.

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) production

Adenosine Triphosphate (ATP)

The fuel for cellular processes like growth, cell division and material support.

Chloropasts

Organelles in plants that use light energy to make food from water and carbon dioxide in photosynthesis; creates glucose.

Golgi Apparatus

Prepares proteins for their specific jobs by packaging them into vesicles, which transport them to where they need to go.

Vesicles

Small membrane sacs that specialize in moving products into, out of, and within a cell

Vacuoles

Organelles which store food, water, and waste. Plant cells usually have one large vacuole whereas animal cells have several smaller vacuoles.

Semipermeable membrane

Referring to how all membranes allow some molecules to pass through but do not allow other molecules to pass through.

Passive transport

the movement of substances across a cell membrane without the use of energy by the cell

Diffusion

The movement of substances from an area of higher concentration to areas of lower concentration. Typically, it happens through a membrane until the concentration is even both in and outside the cell. (equilibrium)

Osmosis

Diffusion of water molecules only through a membrane. Semipermeable membranes allow for water to pass through until equilibrium is achieved.

Facilitated Diffusion

Movement of specific molecules across cell membranes through proteins like carrier and channel proteins. Does not require energy.

Why does facilitated diffusion exist?

Because some molecules are too large or chemically unstable to travel through a membrane by diffusion.

Carrier Proteins

Carry large molecules (ex: glucose) through the cell membrane

Channel Proteins

Form pores trough the membrane- atomic particles like sodium and potassium travel through these.

Active Transport

Energy-requiring process that moves material across a cell membrane against a concentration difference. Moves from lower concentration to higher concentration.

Why is Active Transport importiant?

Cells can take in needed nutrients from the environment through proteins which utilize active transport.

Endocytosis

The process during which a cell takes in a substance by surrounding it with the cell membrane.

Exocytosis

The process during which a cells vesicles release their contents outside of a cell.

Volume

The amount of space in a cell.

Why do cell membranes need to be large?

Cell membranes need to be large to support the cell's requirements for nutrients and waste removal.

What is cellular respiration?

A series of chemical reactions that convert the energy in food molecules into usable energy.

How does cell growth affect volume and surface area?

As a cell grows, its volume increases faster than its surface area.

What is the usable energy produced by cellular respiration called?

ATP

Where does cellular respiration occur in the cell?

In the cytoplasm and mitochondria.

What is glycolysis?

The first step of cellular respiration is the breakdown of glucose into smaller parts. This process uses and creates some ATP.

What does glycolysis produce?

Some ATP molecules.

Second step of Cellular Respiration

When mitochondria break down glucose from glycolysis, requiring oxygen and produces large amounts of ATP. Waste of Carbon Dioxide and Water are generated.

Fermentation

A reaction that eukaryotic and prokaryotic cells can use to obtain energy from food when oxygen levels are low.

Fermentation makes less ATP compared to this...

Cellular Respiration.

Fermentation occurs in the...

Cytoplasm

Lactic Acid Fermentation

When glucose in converted into ATP and creates waste of Lactic Acid.

What is Lactic Acid Fermentation used in?

Bacteria can create cheese, yogurt, and sour cream using this. Muscle cells in humans and other animals can use this to obtain energy during exercise.

Alcohol Fermentation

Some types of bacteria and yeast creating ATP by producing a type of alcohol called ethanol and Co2.

Photosynthesis

A series of chemical reactions that convert light energy and C02 into the food energy molecule Glucose; give off Oxygen. (similar to Chloroplasts card)

Chloroplast Reactions

CO2 + H2O + Light = Glucose + Oxygen- oxygen is released into atmosphere

Cellular Respiration and Photosynthesis cycle:

Light Energy-> Chloroplast-> Glucose and Oxygen-> Mitochondrion-> Carbon Dioxide, Water, and ATP

What passes through a cell using passive transport?

Small molecules, oxygen, and carbon dioxide.

What are the three types of passive transport?

Facilitated diffusion, simple disfusion, osmosis

How do substances move in passive transport?

Higher to lower concentration

What is used in facilitated diffusion to assist the transport of sugar and sodium molecules?

Carrier and channel proteins.

What is only used in active transport?

Energy.

How do substances move in active transport?

Lower to higher concentration

Which proteins are used in active and passive transport

Carrier proteins

What does a cell do to a substance in endocytosis?

Surrounds it and brings it into the cell.

Which structures join with the cell's membrane during exocytosis?

Vesicles

Lysosome (not important in our unit but still mentioned)

cell organelle filled with enzymes needed to break down certain materials in the cell

Centrosome (not important in our unit but still mentioned)

A structure present in the cytoplasm of animal cells that functions as a microtubule-organizing center and is important during cell division. A centrosome has two centrioles.

Amyloplast (not important in our unit but still mentioned)

Unpigmented plasmids that store starch grains, abundant in cells of stems, tubers, and seeds