Sections 7.1 and 7.3 Quiz

What did Robert Hooke do and when?

1) He made a simple microscope and viewed a piece of cork. He saw small chambers which he called cellulae. This was how cells were discovered.

2) 1665.

Why are cells called cells?

The word cell comes from cellulae which meant small chamber. Robert Hooke called cells cellulae because they reminded him of the rooms in a monastery that monks lived in.

What did Anton Van Leeuwenhoek do?

He was inspired by a book written by Hooke to design his own microscope and he saw living organisms in pond water and he viewed many other substances.

What is a cell?

The basic structural and functional unit of all living organisms.

What did Matthias Schleiden do and when?

1) Studied plant tissues and concluded that all plants are made of cells.

2) 1838.

What did Theodore Schwann do and when?

1) Studied animal tissues and concluded that all animals are made of cells.

2) 1839.

What did Rudolf Virchow do and when?

1) Proposed that all cells are produced from the division of previous cells.

2) 1855.

What does the cell theory state?

1) All living organisms are made of one or more cells.

2) Cells are the basic unit of structure and organisation of all living things.

3) Cells arise only from preexisting cells, with cells passing down copies of their genetic information to their daughter cells.

What are compound light microscopes? What is their maximum magnification and why?

1) Microscopes that use a series of glass lenses and visible light to produce a magnified and inverted image.

2) 1000X.

3) Objects cause light to scatter, so images above 1000X are blurred.

What is a transmission electron microscope?

A microscope passes electrons through a thinly sliced specimen to a screen where the image of the cell’s interior forms.

How must a specimen be prepared for an electron microscope?

They must be thinly sliced and stained with heavy metals, meaning that they must be dead.

What are scanning electron microscopes?

Microscopes that directs electrons over the surface of a specimen and forms a 3D image of the specimen’s surface.

What is a scanning tunneling electron microscope?

A microscope that brings a charged tip very close to the surface of the specimen so that the electrons tunnel through the small gap between the specimen and the tip. This allows scientists to form 3D images of objects as small as atoms. This can be used with live specimens.

What is an atomic force microscope?

A microscope that measures the various forced between the tip of a probe and the surface of a specimen.

What trait do all cells have in common? Define it.

1) They have a plasma membrane.

2) A boundary that helps control what enters and leaves the cell.

What are the two main categories of cells? Define them.

1) Eukaryotic cells - cells with a nucleus and organelles that tend to be larger than prokaryotic cells.

2) Prokaryotic cells - cells without a nucleus and membrane bound organelles.

What is the endosymbiont theory?

A theory that states that one prokaryotic cell started living inside another prokaryotic cell and became an organelle.

What is the cytoplasm?

The environment inside the cell’s plasma membrane.

Where do the chemical processes of prokaryotic cells happen? Eukaryotic cells?

1) Inside the cytoplasm.

2) Inside specialized organelles.

What is the cytoskeleton?

The cytoskeleton is a supporting network of long, thin protein fibers that form a framework for the cell and provide an anchor for the organelles inside the cell.

What is the cytoskeleton composed of? What do they do?

1) Microtubules and microfilaments.

2) Microtubules and microfilaments are constantly disassembling and assembling in order to slide past one another and allow the cell and the organelles within it to move.

Do organelles simply float in the cytoplasm? How are they supported?

No, instead they are supported by microtubules and microfilaments.

What is the nucleus? What is it surrounded by? Define it.

1) the cell’s managing structure which contains most of the cell’s DNA (which is used for making proteins for cell growth, function, and reproduction).

2) The nuclear membrane.

3) A double membrane that is similar to the plasma membrane, except it contains pores for substances to move in and out of the nucleus.

What are ribosomes? What are they made of? Why are they unique?

1) Organelles that manufacture proteins.

2) RNA and proteins.

3) They are not membrane bound like other organelles.

What do free floating ribosomes do? Bound ribosomes?

1) produce proteins for use within the cytoplasm.

2) produce proteins that will be bound within membranes or used by other cells.

What is the endoplasmic reticulum?

a membrane system of folded sacs and interconnected channels that serves as a site for lipid and protein synthesis.

What is the rough ER responsible for? The smooth ER?

1) The rough endoplasmic reticulum is responsible for protein synthesis and is covered in ribosomes.

2) The smooth endoplasmic reticulum does not have ribosomes and is responsible for synthesizing complex carbohydrates and lipids.

What is the golgi apparatus? What are vesicles?

1) a flattened sac of membranes that modifies, sorts, and packages proteins into sacs called vesicles.

2) Vesicles help transport proteins out of the cell.

What are vacuoles?

membrane-bound vesicles for the temporary storage of materials within the cytoplasm.

What are lysosomes?

Vesicles that contain substances that digest excess or worn-out organelles and food particles.

What are centrioles?

a structure that aids in cell division formed by groups of microtubules.

What is the mitochondrion? Why does it have both and inner and outer membrane?

1) The powerhouse of the cell.

2) an outer and inner membrane that provides surface area for breaking down sugars and turning them into usable energy.

What are chloroplasts? What are thylakoids?

1) Organelles that carry out photosynthesis.

2) Small compartments within the inner membrane of chloroplasts.

What is the cell wall? What is it composed of?

1) A thick, rigid mesh of fibers that surrounds the outside of the cell membrane which protects the cell and gives it support.

2) Cellulose.

What are cillia?

short projections that look like hairs that aid in movement and feeding.

What are flagella?

Long hairlike projections that move in a whipping motion in order to move the cell.

What unique organelles are found in plant cells? What unique organelles are found in animal cells?

1) Plastids and the cell wall.

2) Centrioles and lysosomes.