Chapter 4
State differences between Eukaryotic cells and Prokaryotic cells.
1. prokaryotic cells have naked DNA found in cytoplasm in region named nucleoid. eukaryotic cells have chromosomes made up of DNA and protein found in the nucleus enclosed in the nuclear envelope 2. prokaryotic cells do not have mitochondria eukaryotic does 3. prokaryotic have small ribosomes eukaryotic have large ribosomes 4. prokaryotic have no or few membrane-bound organelles eukaryotic have many
The smooth ER is the primary site for the synthesis of PROTEINS and cholesterol needed to make membranes.__________________. ture or false
False phospholipids
Proteins made on ribosomes may be further modified within which organelle?
Golgi complex
aerobic respiration
Respiration that requires oxygen
Evidence that all living cells have a common origin is best illustrated by the:
basic similarities in cell structure and chemistry.
What cellular structure is unique to plant cells and some photosynthetic fungi?
chloroplasts
Which process is a function of peroxisomes?
detoxification
Apoptosis
process of programmed cell death
List the organelles that are part of endomembrane system.
nucleus membrane golgi apparatus vacuole vesicles rough ER smooth ER
A glycoprotein destined for secretion from the cell would move through the Golgi complex which sequence?
cis face to medial region to trans face
rodlike structures consisting of actin
microfilaments
What is found between the primary walls of adjacent cells for cells to adhere tightly to one another?
middle lamella
Which of the following organelles plays an important role in apoptosis, or programmed cell death?
mitochondria
What is one cellular characteristic found in all prokaryotic and eukaryotic cells?
plasma membrane
encloses an internal thylakoid membrane
plastids
The cellular structure indicated by the arrow in the accompanying figure is responsible for:
protein synthesis.
What does the nucleolus, within the nucleus, synthesize?
ribosomal RNA
Cell fractionation
technique in which cells are broken into pieces and the different cell parts are separated
What is the primary function of mitochondria?
transformation of energy
The micrometer (μm) is the most convenient unit for measuring cells. True or false?
true
Which organelle can be considered a sorting, processing and packaging center?
Golgi complex
The smooth ER is the primary site for the synthesis of phospholipids and cholesterol needed to make ____.
cell membranes
How does the nucleus store information?
in the form of DNA
Mitochondria play an important role in cell NECROSIS.__________________. true or false
False apoptosis
Which strategy is most effective for larger cells to have an effective surface area to volume ratio?
having thin, finger-like projections
Golgi complexes of prokaryotic cells produce extracellullar polysaccharides that are used to make cell walls.__________________. True or false
False plant
Homeostasis
Appropriate regulation and balance in internal environment
Identify two structural components of the cytoskeleton, and briefly describe their function(s)
intermediate filaments: provides mechanical support for the plasma membrane microtubules: is to help support and give shape to the cell
Photosynthesis
Conversion of light energy from the sun into chemical energy.
The ratio of the size of the image seen with the microscope to the actual size of the object is called:
magnification.
large membranous sacs of plants and fungi
va
Magnification
the ratio of an object's image size to its real size
Describe three functions of cell membranes.
1. keeping the contents of cell within it 2. protecting self from foreign materials 3.diffusing important molecules from outside to inside the cell and also discarding waste product from within the cell
Resolving power
A measure of the clarity of an image; the ability of an optical instrument to show two objects as separate.
Organelles
A tiny cell structure that carries out a specific function within the cell
list the similarities and differences between the function of the chloroplasts and mitochdria. include the identification of specific structures in you comparison
Both have outer and inner membranes and provides the cell with energy. Chloroplast only occurs in plants and conducts photosynthesis. Mitochondria occurs in both plants and animal cells and conducts cellular respiration
Nucleus
Control center of the cell. Contains DNA.
Why are membrane-bounded organelles able to facilitate faster chemical reactions?
Enzymes are organized close together on the membrane surface.
consists of RNA and protein within another organelle
Nucleolus
ribosomes stud its outer surface
Rough ER
How does the scanning electron microscope differ from the transmission electron microscope?
The SEM gives a three-dimensional image of the object being studied.
Mitochondria
The organelles in which nutrients are converted to energy and enclosed membrane
Which statements about centrioles is false?
They have a 9 + 2 arrangement of microtubules.
DNA is associated with RNA and certain proteins forming chromatin.__________________. True or false?
True
Why is it advantageous for cells to be small?
a small cell has a small volume relative to surface area, thereby increasing efficient transport
DNA is associated with certain proteins, forming a complex called:
chromatin
The outer membrane of the nuclear envelope is continuous with the membrane of the ____ and is usually covered with attached ribosomes
endoplasmic reticulum
membranous sacs in animals
lysosome
Plants lack organ systems for disposing of toxic metabolic waste products. Their cells' vacuoles are like what animal cell organelle?
lysosomes
Chromatin
the readily stainable substance of a cell nucleus consisting of DNA and RNA and various proteins