Biology Chapter 4: A tour of the cell
How is the nucleic region of a prokaryotic cell different from the nucleus of a eukaryotic cell?
There is no membrane enclosing the prokaryotic nucleus region.
What is the relationship between chromosomes, chromatin, and DNA?
chromosomes are made of chromatin, wicks is a combination of DNA and proteins
You look into a microscope and view an unknown cell. What might you see that would tell you whether the cell is prokaryotic or eukaryotic?
A Nucleus
Place the following cellular structures in the order they would be used in the production and secretion of a protein: Golgi apparatus, nucleus, plasma membrane, ribosome, transport vesicle.
Nucleus, ribosome, transport vesicle, Golgi apparatus, plasma membrane.
Ribosomes
a cellular structure consisting of RNA and protein organized into two subunits and functioning as the site of protein synthesis in the cytoplasm. The ribosomal subunits are constructed in the nucleolus and then transported to the cytoplasm where they act.
organelles
little organs, found in eukaryotic cells, membrane enclosed structures that perform specific functions, and prokaryotic cells do not.
Explain how each word in the term fluid mosaic describes the structure of a membrane.
A membrane is fluid because its components are not locked into place. A membrane is mosaic because it contains a variety of suspended proteins.
What is cellular respiration/
A process that converts the chemical energy of sugars and other foods molecules to chemical energy in the form of ATP
Name two similarities in the structure or function of chloroplasts and mitochondria. Name two differences.
Both organelles use membranes to organize enemies and both provide energy to the cell. But chloroplasts capture every from sunlight during photosynthesis, whereas mitochondria release energy from glucose during cellular respiration. Chloroplasts are only in photosynthetic plants and protists, whereas mitochondria are in almost all eukaryotic cells.
Compare and contrast cilia and flagella
Cilia and flagella have the same basic structure, are made from microtubules, and help move cells or move fluid over cells. Cilia are short and numerous and move back and forth. Flagella are longer, often occurring singly, and they undulate.
Two types of vacuoles:
Contractile vacuole and central vacuole
Identify which of the following structures includes all the others in the list:rough ER, Smooth ER, endomembrane system, the golgi apparatus?
Endomembrane system
How can defective lysosomes result in excess accumulation of a particular chemical compound in a cell?
If the lysosomes lack an enzyme needed to break down the compound the cell will accumulate an excess of that compound.
cell theory
states that all living things are composed of cells and that all cells come from earlier cells.
What function does the organization of phospholipids into a bilayer in water serve?
the bilayer structure shields the hydrophobic tails of the phospholipids from water while exposing the hydrophilic heads to water.
Chromatin
the combination of DNA and proteins that constitutes chromosomes; often used to refer to the diffuse, every extended form taken by the chromosomes when a eukaryotic cell is not dividing.
From which important class of biological molecules are the microtubules of the cytoskeleton made?
Protein
A type of cel called a lymphocyte makes proteins that are exported from the cell. You can track the path of these proteins within the cell from production through export by labeling them with radioactive isotopes. Identify which of the following structures would be radioactively labeled in your experiment, listng them in the order in which they would be labeled; Chloroplasts, golgi appararts, plasma membrane, smooth er, rough er, nucleus, mitochondri
Rough ER, golgi apparatus, plasma membrane
What does photosynthesis accomplish?
The conversion of light energy to chemical energy stored in food molecules.
Lysosome
a digestive organelle in eukaryotic cells; contains enzymes that digest the cells foods and wastes.
Phospholipid bilayer
a double layer of phospholipid molecules(each molecule consisting of a phosphate group bonded to two fatty acids) that is the primary component of all cellular membranes
Nuclear envelope
a double membrane, perforated with pores, that encloses the nucleus and separates it from the rest of the eukaryotic cell
Chromosomes
a gene carrying structure found in the nucleus of a eukaryotic cell and most visible when compacted during mitosis and meiosis; also, the main gene carrying structure of a prokaryotic cell. Each chromosome consists of one very long threadlike DNA molecule and associated proteins
Flagella
a long appendage that propels protists through the water and moves fluids across the surface of many tissue cells in animals. a cell may have one or more flagella
central vacuole
a membrane enclosed sac occupying most of the interior of a mature plant cell, having diverse roles in reproduction, growth, and development.
Vacuoles
a membrane-enclosed sac, part of the endomembrane system of a eukaryotic cell, having diverse functions.
vesicles
a membranous sac in the cytoplasm of a eukaryotic cell.
Cytoskeleton
a meshwork of fine fibers in the cytoplasm of a eukaryotic cell; includes microfilaments, intermediate filaments, and microtubules.
What is the role of mRNA in making a protein?
a molecule of mRNA carries the genetic message from a gene (DNA) to ribosomes that translate it into protein
Phospholipids
a molecule that is part of the inner bilayer of biological membranes, having a hydrophilic head and a hydrophobic tail
rough endoplasmic reticulum
a network of interconnected membranous sacs in a eukaryotic cell's cytoplasm. rough er membranes are studded with ribosomes that make membrane proteins and secretory proteins. the rough er constructs membrane from phospholipids and proteins.
smooth endoplasmic reticulum
a network of interconnected membranous tubules in a eukaryotic cell's cytoplasm. smooth er lacks ribosomes, enzymes embedded in the smooth er membrane function in the synthesis of certain kinds of molecules , such as lipids.
endomembrane system
a network of organelles that partitions the cytoplasm of eukaryotic cells into functional compartments. some to the organelles are structurally connected to each other, whereas others are structurally separate but functionally connected by the traffic of vesicles among them.
Cilia
a short appendage that propels some protists through the water and over fluids across the surface of man tissue cells in animals
Nucleolus
a structure within the nucleus of a eukaryotic cell where ribosomal RNA is made and assembled with proteins to make ribosomal subunits; consists of parts of the chromatin DNA, RNA transcribed from he DNA, and proteins imported from the cytoplasm.
transport vesicles
a tiny membranous sphere in a cells cytoplasm carrying molecules produced by the cell. The vesicle buds form he endoplasmic reticulum or Golgi apparatus and eventually fuses with another organelle or the plasma membrane, releasing its contents.
Organelles with their funcitons
a3, b1, c5, d2, e4 Ribosomes-protein synthesis Microtubules-movement Mitochondria-Cellular respiration Chloroplasts-photosynthesis Lysosomes-digestion
endoplasmic reticulum
an extensive membranous netwrok in a eukaryotic cell, continuous with the outer nuclear membrane and composed of ribosome-studded (rough) and ribosome-free(smooth) regions
Chloroplasts
an organelle found in plants and photosynthetic protists. enclosed by two membranes, a chloroplast absorbs sunlight and uses it to power the synthesis of organic food molecules.
Mitochondria
an organelle in eukaryotic cells where cellular respiration occurs. enclosed by two concentric membranes, it is where most of the cells ATP is made.
golgi apparartus
an organelle in eukaryotic ces consisting of stacks of membranes sacs that modify, store, and ship products of the endoplasmic reticulum
Extracellular matrix
animal cells lack a cell wall, but most animal cells secrete a sticky coat called the extracellular matrix
Plasma membrane
barrier of cells, regulates the traffic of molecules between the cell and its surroundings
Compare and contrast cilia and flagella
both are appendages that aid in movement and that extend from the surface of a cell. Cells with flagella typically have on long flagellum that propels the cell in a whiplike motion; cilia are usually shorter, are more numerous , and beat in a coordinated fashion.
Name two structures that may be found in animal cells but not plant cells:
centrioles and lysosomes
Name three structures in plant cells that animals lack:
chloroplasts, a central vacuole, and a cell wall
antibiotics
drugs that disable or kill infectious bacteria
cells are in two basic categories
eukaryotic and prokaryotic
Fluid mosaic
fluid because molecules can move freely past one another and mosaic because of the diversity of proteins that fat like icebergs in the phospholipid sea.
Prokaryotic cells
found in organisms of the domains bacteria and archaea, know as prokaryotes
Ciprofloxacin
is the antibiotic of choice to combat anthrax causing bacteria, targets an enzyme that bacteria need to maintain their chromosome structure.
nucleus
most important organelle, surrounded by a double membrane
What makes rough ER rough?
ribosomes attached to the membranes
The ER has two distinct regions that differ in structure and function. Lipids are synthesized within the ___; and proteins are synthesized within the ____?
Smooth ER; rough ER
What is the relationship between the Golgi apparatus and the ER in a protein secreting cell?
The Golgi apparatus receives proteins from the ER via vesicles, processes the proteins, and then disputed them in vesicles.
nucleoid
nucleus like region which is not partitioned form the rest of the cell by membranes
DNA controls the cell by transmitting genetic messages that result in protein production. Place the following organelles in the order that represents the flow of genetic info from the DNA throughout eh cell; nuclear pores, ribosomes, nucleus, rough er, golgi apparatus
nucleus, nuclear pores, ribosomes, rough er, Golgi apparatus
Eukaryotic cells
organisms of the domain Eukarya including protists, pants, fungi, and animals
what was the first antibiotic discovered and when?
penicillin in 1920
Name four structures found in both prokaryotic and eukaryotic cells:
plasma membrane, chromosomes, cytosol, and ribosomes
What is the function of ribosomes?
protein synthesis
cytoplasm
the region of the cell outside the nucleus and within the plasma membrane
Microtubules
the thickest of the three main kinds of fibers making up the cytoskeleton of a eukaryotic cell; a straight hollow tube made of globular proteins called tubules. microtubules form the basis of the structure and movement of cilia and flagella.
cytosol
thick jellylike fluid, in which cellular components are suspended.
What is the goal of antibiotic treatment?
to knock out invading bacteria while doing no damage to the human host
