bio 101 study guide : module 4
Cytosol = fluid inside the cell; surrounds each organelle
Cytoplasm = entire region between nucleus and plasma membrane
Cell wall = NOT found in animal cells; functions to protect the cell, provides strength and rigidity, and prevents the cell from bursting; found in plants, fungi, and some protists
Cell membrane = both in plant and animals cells; functions to regulate passage of molecules in and out of the cell and protects the cell from the surrounding environment
Nucleus = command center of cell; contain DNA; provides the “blueprints” for building proteins and maintaining the proper function of the cell; surrounded by a double-layered nuclear membrane
Nucleolus = ribosomal RNA (rRNA) is produced
Chromatin = DNA combines with protein
Chromosomes = thread-like structures located in the nucleus of eukaryotic cells that carry genetic information
Ribosomes = found in the cytoplasm/cytosol; “machines” that help translate mRNA into proteins and amino acids; protein synthesis occurs here
Smooth endoplasmic reticulum = helps maintain cell health and function; synthesis of steroids; storage of ions like calcium; forms transport vesicles to carry substances around the cell
Rough endoplasmic reticulum = site of the synthesis and initial transport of secreted protein; characterized by ribosomes that dot the surface; make phospholipids and new plasma membrane which is transferred to other parts of the cell
Golgi apparatus = stacks of flattened membrane stacks; processes proteins and packages them into vesicles to be transported within the cell or secreted; receives, refines, stores, and distributes chemicals inside the cell
Lysosomes = provide a location for dangerous chemical reaction to take place; filled with digestive (hydrolytic) enzymes; found in animal cells only
Vacuoles = large membrane-bound storage saces; they contain nutrients or water; plant cells have the largest membrane
Chloroplasts = convert light to energy to chemical energy in plant cells; perform photosynthesis
Mitochondria = powerhouse of the cell; organelles perform cell respiration; uses ATP; found both in plant and animal cells
Cytoskeleton = network of protein fibers (microtubules, microfilaments, intermediate filaments); provides structure and support for cell; gives the cell shape; anchors organelles inside cells; aids in chromosome movement and separation during cell division
Microtubules = act like train tracks; organelles can crawl along microtubules to move around inside the cell; small molecules can be shipped inside the microtubule
Cilia = motile appendage; short hair-like appendages; made of microtubules; back and forth wafting movement; found in respiratory tract; propels protists through fluid
Flagella = motile appendage; hair-like appendage; made of microtubules; has whip-like movements; found on sperm; propels protists through water
Cells
What is the smallest unit that displays all the properties of life? cells
What does unicellular mean? made up of one cell
What does multicellular mean? made up of many cells
Are prokaryotes unicellular or multicellular? unicellular
Compare and contrast prokaryotic and eukaryotic cells
Which is larger? eukaryotic
Which is older evolutionarily? prokaryotic
Which has just 1 circular chromosome? prokaryotic
Which has a nucleus? eukaryotic
Which has membrane-bound organelles? eukaryotic
Do prokaryotes have a cell wall? yes
Do prokaryotes have a cell membrane? yes
Compare and contrast eukaryotic plant and animal cells.
What 3 things are found in plant cells and not in animal cells? central vacuole, cell wall, and chloroplast
Do animal cells have a cell wall? no
What is stored in the central vacuole? nutrients or water
What is the function of chloroplasts? converting light energy to chemical energy in the plant cells
Do plant cells have mitochondria? yes
What is cytoplasm? entire region between the nucleus and plasma membrane
What is cytosol? fluid inside the cell; surrounds each organelle
What is a cell organelle? specialized structure within a cell that performs a specific function
What is the function of the plant cell wall? protect the cell, provide strength and rigidity, prevent the cell from bursting
Describe the structure of the plasma membrane and the structures found within it.
What is the function of the plasma membrane? regulate the passage of molecules in and out of the cell and protects; protect the cell from the surrounding environment
Where is extracellular fluid (ECF) found? sticky outer coat on animal cells
Which organic molecule is the plasma membrane mainly composed of? phospholipids
What is the meaning of the term “bilayer”? double layer
Which part of a phospholipid is hydrophilic? head
Which part of a phospholipid is hydrophobic? tail
What is the function of cholesterol in the cell membrane? to maintain membrane fluidity, stability, and integrity
What is the purpose of integral proteins in the cell membrane? transport, communication and structural support
What are the functions of peripheral proteins on the cell membrane? support, signaling, and enzyme activity
Explain why the term “fluid mosaic” is used to describe plasma membranes. structure and behavior of the plasma membrane
What is the correct organization of phospholipids in a plasma membrane? C
What is the extracellular matrix? sticky outer coat on animal cells
What are some functions of the extracellular matrix? attracts water to cell; anchors cell; allows communication between cells of the tissue; acts as a marker for recognition of cell
What is a proteoglycan/glycoprotein composed of? a core protein attached to long chains of carbohydrates called glycosaminoglycans; a protein with short, branched carbohydrate chains
What is a glycolipid composed of? a lipid (fatty acid) embedded in the cell membrane
What are the functions of glycoproteins and glycolipids?
glycoproteins:
cell recognition; cell signaling; structural support; immune response
clycolipid:
cell recognition
membrane stability
protection
Nucleus
What is the function of the nucleus? command center of cell
What is the wrapper for the nucleus? double layered nuclear membrane (nuclear envelope)
Are there holes in the nuclear envelope? yes because it allows substances to move in and out of the nucleus
Genetic material
Does chromatin 1 and chromosome 1 have the same genetic information? yes, but they exist in different structural forms
What is the difference between chromatin and chromosomes?
chromatin:
uncoiled, loose form of DNA
DNA wrapped around histone
allows gene expression, replication, and DNA repair
during interphase
DNA is accessible for transcription and replication
chromosome:
condense, tightly packed form of DNA
highly coiled and compact DNA
ensures accurate DNA distribution during cell division
during cell division (mitosis or meisosis)
DNA is tightly packed, making it less accessible
In a dividing cell would you see chromatin or chromosomes? chromosomes
Nucleolus
What is made by the nucleolus? rRNA
Ribosomes
What is the function of ribosomes? protein synthesis; “machines” that help translate mRNA into proteins and amino acids
What are ribosomes made of? rRNA and proteins
What are the names of the two ribosomal subunits? prokaryotic and eukaryotic
Rough Endoplasmic Reticulum (RER)
What is the function of the RER? site of the synthesis and initial transport of secreted protein; makes phospholipids and new plasma membrane which is transferred to other parts of the cell
What is stuck all over the RER making it rough? ribosomes
Smooth Endoplasmic Reticulum
What can the SER synthesize? steroids
What is another function of the SER? storage of ions
Golgi apparatus
What is the function of the Golgi apparatus? processes proteins and packages them into vesicles to be transported within the cell or secreted
To help remember its function, we compared the Golgi apparatus to a: post office/ups store
Lysosomes
What is contained inside a lysosome? filled with digestive (hydrolytic) enzymes
What is the function of lysosome? provide a location for dangerous chemical reactions to take place
Why not digest food in the cytoplasm? Why do it inside a lysosome? breaks down damaged cell organelles recycling the components
Vacuole
What is the general function of vacuoles? storage; structural support; can hold toxic substances protecting the cell; helps regulate osmotic pressure
What is stored in the central vacuole of plants? contains water
What do animal cells store in their vacuoles? contains nutrients
What other function do vacuoles serve in animal cells? transport of material into the cell
Chloroplast
What is the function of chloroplasts? convert light energy to chemical energy
Why are chloroplasts green? the grana are stacks of membranes that contain a green pigment called chlorophyll
Describe the membrane of a chloroplasts. Is it single or double? double membrane
Mitochondria
What is the function of the mitochondrion? powerhouse of the cell; perform cell respiration
What is the energy molecule that cells use that is created by the mitochondrion? ATP
What is ATP short for? adenosine triphosphate
Describe the mitochondria membrane. Single or double? double membrane
Are mitochondria found in plant cells? yes
Explain Endosymbiotic Theory and describe the organelles that are included in this theory
What two organelles are endosymbiotic? mitochondria and chloroplasts
What is the evidence that the organelles are prokaryotes living inside eukaryotes? own DNA, replicated independently, same size as bacterial ribosomes, double membrane is present
What is the advantage for the eukaryotic cell? producing more energy, perform photosynthesis, and larger and more complex organisms
Cytoskeleton
What are the functions of the cytoskeleton? network of protein fibers; provides structure and support for cell; gives it shape; anchors organelles inside cells; aids in chromosome movement and separation during cell division
Microtubules
What is the function of microtubules? acts like a train track; crawl along microtubules to move around inside the cell; small molecules can be shipped inside the microtubule
If something can’t fit inside a microtubule for movement, how can the microtubule help it move? it can still be carried along by motor proteins
What is ameboid movement? rapid degradation and rebuilding of microtubules allows crawling movement
Flagella
What is the function of flagella? has whip like movements
What is the only human cell with a flagellum? sperm cell
Cilia
What is the function of cilia? back and forth wafting movement
Where are cilia found in humans? respiratory tract