Bio: Cells 2

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demonstrate the relationship between surface area and volume.

A large, round cell has a lower surface area to volume ratio than a thin, flat cell. Cellular extensions increase the cell's surface area to volume ratio. Root hairs, flat leaves, and feathery gills increase surface area.

Golgi apparatus

A system of membranes that modifies and packages proteins for export by the cell

Membrane

All cells have a cell __________ , that surrounds the cytoplasm and forms a boundary between the cell and its environment.

Choice, centrioles present centrioles present

Animal Cell

In cell membranes, the phospholipids are arranged into a

Bilayer

lipid-rich boundary between the cells and outside environment

Cell membrane

Eukaryotic cells

Cells that contain membrane-bounded organelles and a nucleus

Types of light microscope

Confocal and Compound

all cell contents except the nucleus

Cytoplasm

the cell's genetic information

DNA

how DNA in the nucleus is used to specify protein production by the cell.

DNA is copied into mRNA in the nucleus, and the mRNA is used outside the nucleus to make proteins.

Rudolph Virchow

Discovered all cells come from other cells

What is a network of sacs and tubules extending off the nuclear envelope and is where proteins and lipids are produced?

Endoplasmatic Reticulum

Peroxisomes are organelles that originate at the ______ and contain enzymes that dispose of toxic substances.

Endoplasmatic reticulum

Protists, plants, fungi, and animals are organisms in the domain

Eukarya

The ______ is a series of flattened sacs that sorts and packages materials into vesicles to be sent to the cell membrane.

Golgi Apparatus

Lysosomes originate from vesicles that bud from the ______, and the enzymes contained in lysosomes are synthesized in the ______.

Golgi apparatus; rough ER

attach to the endoplasmic reticulum.

If an mRNA specifies a protein to be used in the cell membrane or to be secreted from the cell, this protein is made on ribosomes that

cell with more surface area relative to volume

What cell shape has the most efficient exchange of materials between the cell's interior and exterior?

Peroxisomes

What organelle protects all eukaryotic cells from toxic substances or toxic by-products of chemical reactions?

Description of a confocal microscope

White or laser light is focused through a lens, and the image passes through a pinhole.

Eukarya

possible larger cell size, fatty acids in the cell membrane, and nucleus present

contractile vacuole in Paramecium matches

pump excess water out of the cell

roles that membranes play in cells.

receive and respond to external stimuli enclose organelles in eukaryotic cells transport substances into and out of the cell

Proteins to be secreted outside of a eukaryotic cell are formed at ribosomes on the surface of the ______ endoplasmic reticulum.

rough

What plant cell organelle can occupy up to 90% of the cell volume and can exert turgor pressure against the cell membrane when it acquires water?

central vacuole

Choice, contains enzymes, salts, pigments, sugars, and acids contains enzymes, salts, pigments, sugars, and acids

central vacuole in plants

differ between domains Bacteria and Archaea.

chemical composition of flagella molecules that compose the cell membranes evolutionary relationship to eukaryotes

present in plant cells but not in animal cells.

chloroplasts cell wall

The two-layered nuclear envelope separates the nucleus of a cell from the

cytoplasm

Organelles called lysosomes contain ______ that break down food particles, old organelles, and other cellular debris.

enzymes

Bacteria

small cell size, fatty acids in the cell membrane, and prokaryotic

Archaea

small cell size, nonfatty acid lipids in the cell membrane, and prokaryotic

Lipids, detoxifying enzymes, and membrane components are produced and stored in the ------------ endoplasmic reticulum.

smooth

What is the function of mitochondria in eukaryotic cells?

extract energy from food

Nuclear pores

holes in the nuclear envelope that allow materials to pass in and out of the nucleus

functions of the smooth endoplasmic reticulum.

house enzymes that detoxify drugs and poisons synthesize lipids

The head of a phospholipid is ______, meaning its polar covalent bonds attract water, but the tails of a phospholipid are ______ and thus water-insoluble.

hydrophilic; hydrophobic

Nuclear envelope

layer of two membranes that surrounds the nucleus of a cell

ways that cells avoid surface area limitations.

long or thin shape efficient transportation system within cell

functions of lysosomes.

lyse captured bacteria breakdown large food particles into smaller subunits dismantle worm-out organelles

Archaeans called methanogens use carbon dioxide and hydrogen from the environment and produce ______ as a byproduct

methane

electron

microscope allows resolution of objects that are about 5 nanometers in size

about prokaryotes.

most ancient forms of life on Earth simplest types of life lack a nucleus

characteristics of eukaryotic cells.

nucleus larger than prokaryotic cells system of internal membranes

components of the cytoplasm

organelles cytosol ions and enzymes cytoskeleton

components of phospholipid molecules

two fatty acids phosphate group glycerol molecule

The enzymes in one lysosome could not digest a cell because the ______ of the lysosome is much ______ than the neutral cytoplasm, and therefore the lysosome enzymes would not be able to function fully in the cell cytoplasm.

pH

describe compound microscopes.

type of light microscope uses two or more lenses to focus visible light commonly used in biology lab courses

describe electron microscopes

use beam of electrons instead of light provide greater magnification than light microscopes usually require that specimen be killed expensive to build and operate

The protein produced by a free ribosome (left panel) will most likely be ______, while the protein produced by a ribosome attached to the rough ER's membrane (right panel) will most likely be ______.

used in the cytosol; used in the cell membrane

Plant cells have large central ______ where water, salts, and sugars are stored and where materials are broken down and recycled with enzymes similar to lysosomes in animal cells.

vacuoles

Turgor pressure in plant cells results from the expansion of the central vacuole as it fills with

water

Lysosomes are often required to process ______, which reach toxic levels in the brain cells of people with malfunctioning lysosomes (a condition called Tay-Sachs disease).

Lipids

What organelle of the endomembrane system breaks down debris, food, and old cell parts with special dismantling enzymes?

Lysosome

examples in which the ratio of surface area to volume of cells is increased.

Nerve cells are long and thin. Amoebas have extensions of their cell membrane. Paramecia are horizontally flattened in shape.

The ______ found within the nuclear envelope are lined with specialized proteins that allow the transport of substances into and out of the nucleus.

Nuclear pores

allow the passage of regulatory proteins into the nucleus and mRNA molecules out of the nucleus?

Nuclear pores

membrane

Organelles carry out specialized functions in the cell and are enclosed by

Eukarya

Organisms in the domain ______ are made of cells that have a nucleus and membranous organelles.

cell wall and chloroplasts present

Plant Cell

In all cells, RNA and ribosomes play a role in the production of ______, which are molecules that carry out all of the cell's work.

Proteins

What cell structure binds to mRNA coming from the nucleus and manufactures proteins?

Ribosome

structures that manufacture proteins

Ribossome

Light

The ______ microscope is ideal for viewing living cells that are between 200 nanometers and 1 millimeter in size.

transmission; scanning

Two types of electron microscopes are ______ electron microscopes, which pass electrons through a specimen, and ______ electron microscopes, which beam electrons over the surface of a metal-coated specimen.

In the Golgi apparatus, proteins are sorted and packaged into ______ that deliver the proteins to their destinations.

Vesicles

Cytosol

The watery mixture of ions, enzymes, and RNA within the cytoplasm is called the

Based on Carl Woese's work, biologists recognized _____ domains of life.

Three

Most cells have a small size that is less than 0.1 mm in diameter to maximize surface area relative to volume.

True

Enzymes in the lysosomes function at a more ______ pH than the cytoplasm, which means the enzymes only function within the enclosed lysosome, unless all of a cell's lysosomes burst at once.

acid

Enzymes in the Golgi apparatus can synthesize and attach ______ to proteins and lipids, forming glycoproteins and glycolipids.

carbohydrates

liver cells white blood cells

cells that have relatively more lysosomes.


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