BIOB33 MIDTERM EXAM QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS VERIFIED GRADED A++
Plasmalemma
lipid bilayer, containing phospholipids, steroids, proteins, and carbohydrates. Isolation;
protection, sensitivity; support; control of entrance/exit materials
Cytosol
fluid component of cytoplasm; may contain inclusions of insoluble materials. Distributes
materials by diffusion; stores glycogen, pigments, and other materials
Cytoskeleton
proteins organized in fine filaments or slender tubes. Strength and support; movement
of cellular structures and materials
Microvilli
membrane extensions containing microfilaments. Increase surface area to facilitate
absorption of extracellular materials
Centrosomes
cytoplasm containing two centrioles at right angles; each centriole is composed of nine
microtubule triplets. Essential for movement of chromosomes during cell division;
organization of microtubules in cytoskeleton
Cillia
membrane extensions containing microtubule doublets in 9 + 2 array. Movement of
materials over cell surface
,Ribosomes
RNA (60%) + proteins (40%); attached ribosomes bound to rough endoplasmic
reticulum; free ribosomes scattered in cytoplasm. Protein synthesis
Mitochondria
double membrane, with inner membrane folds (cristae) enclosing metabolic enzymes.
Produce 95% of ATP required by cell
Nucleus
nucleoplasm containing nucleotides, enzymes, nucleoproteins, and chromatin;
surrounded by double-layer membrane (nuclear envelope) containing nuclear pores.
Control of metabolism; storage and processing of genetic information; control of protein
synthesis
Nucleolus
dense region in nucleoplasm containing DNA and RNA. Site of rRNA synthesis and
assembly of ribosomal subunits
Endoplasmic Reticulum (ER)
network of membranous channels extending throughout cytoplasm. Synthesis of
secretory products; intracellular storage and transport
Rough ER
has ribosomes bound to membranes. Modification and packaging of newly synthesized
proteins
Smooth ER
lacks attached ribosomes. Lipid, steroid, and carbohydrate synthesis; calcium ion
storage
,Golgi Apparatus
stacks of flattened membranes (cisternae) containing chambers. Storage, alteration,
and packaging of secretory products and lysosomal enzymes
Lysosomes
vesicles containing digestive enzymes. Intracellular removal of damaged organelles or
pathogens
Peroxisome
vesicles containing degradative enzymes. Catabolism of fats and other compounds;
neutralization of toxic compounds generated in the process
X-Ray
form of high-energy radiation that can penetrate living tissue
In the human body, the order of increasing radiodensity is as follows...
... air, fat, liver, blood, muscle, bone
Image with radiodense tissues, such as bone, appears...
... white. While less dense tissues are seen in shades of gray to black
Barium-Contrast X-Ray
in upper digestive tract. Barium is very radiodense. Contours of the gastric and intestinal
lining is seen outlined against the white of the barium solution
CT Scans (CAT)
use a single x-ray source rotating around the body. The x-ray beam strikes a sensor
monitored by a computer. The source completes one revolution around the body every
few seconds. It then moves a short distance and repeats this process
Digital Subtraction Angiography (DSA)
, used to monitor blood flow through specific organs (brain, heart, lungs, kidneys). X-rays
are taken before and after radiopaque dye is administered, and a computer subtracts
details common to both images. Result is a high-contrast image showing the distribution
of the dye
Magnetic Resonance Imagine (MRI)
scan surrounds body with magnetic field about 3000 times as strong as Earth. Affects
protons within atomic nuclei throughout the body, which line up along the magnetic lines
of force like compass needles in Earth's field
Spiral CT Scan (Helical CT Scan)
new form of 3D imaging technology that is becoming increasingly important in clinical
settings. With spiral CT, patient is placed on platform that advances through scanner
while imaging source (usually x-rays) rotates around
Ultrasound
small transmitter contacting skin broadcasts brief, narrow burst of high-frequency sound
and then picks up the echo. The sound waves are reflected by internal structures, and a
picture (echogram) can be assembled from the pattern of echoes
The skin can regenerate effectively, even after considerable damage has
occurred, because...
... cells persist in both epithelial and connective tissue components
Germinative cell divisions replace lost...
... epidermal cells
Mesenchymal cell divisions replace lost...
... dermal cells
COMPLETE SOLUTIONS VERIFIED GRADED A++
Plasmalemma
lipid bilayer, containing phospholipids, steroids, proteins, and carbohydrates. Isolation;
protection, sensitivity; support; control of entrance/exit materials
Cytosol
fluid component of cytoplasm; may contain inclusions of insoluble materials. Distributes
materials by diffusion; stores glycogen, pigments, and other materials
Cytoskeleton
proteins organized in fine filaments or slender tubes. Strength and support; movement
of cellular structures and materials
Microvilli
membrane extensions containing microfilaments. Increase surface area to facilitate
absorption of extracellular materials
Centrosomes
cytoplasm containing two centrioles at right angles; each centriole is composed of nine
microtubule triplets. Essential for movement of chromosomes during cell division;
organization of microtubules in cytoskeleton
Cillia
membrane extensions containing microtubule doublets in 9 + 2 array. Movement of
materials over cell surface
,Ribosomes
RNA (60%) + proteins (40%); attached ribosomes bound to rough endoplasmic
reticulum; free ribosomes scattered in cytoplasm. Protein synthesis
Mitochondria
double membrane, with inner membrane folds (cristae) enclosing metabolic enzymes.
Produce 95% of ATP required by cell
Nucleus
nucleoplasm containing nucleotides, enzymes, nucleoproteins, and chromatin;
surrounded by double-layer membrane (nuclear envelope) containing nuclear pores.
Control of metabolism; storage and processing of genetic information; control of protein
synthesis
Nucleolus
dense region in nucleoplasm containing DNA and RNA. Site of rRNA synthesis and
assembly of ribosomal subunits
Endoplasmic Reticulum (ER)
network of membranous channels extending throughout cytoplasm. Synthesis of
secretory products; intracellular storage and transport
Rough ER
has ribosomes bound to membranes. Modification and packaging of newly synthesized
proteins
Smooth ER
lacks attached ribosomes. Lipid, steroid, and carbohydrate synthesis; calcium ion
storage
,Golgi Apparatus
stacks of flattened membranes (cisternae) containing chambers. Storage, alteration,
and packaging of secretory products and lysosomal enzymes
Lysosomes
vesicles containing digestive enzymes. Intracellular removal of damaged organelles or
pathogens
Peroxisome
vesicles containing degradative enzymes. Catabolism of fats and other compounds;
neutralization of toxic compounds generated in the process
X-Ray
form of high-energy radiation that can penetrate living tissue
In the human body, the order of increasing radiodensity is as follows...
... air, fat, liver, blood, muscle, bone
Image with radiodense tissues, such as bone, appears...
... white. While less dense tissues are seen in shades of gray to black
Barium-Contrast X-Ray
in upper digestive tract. Barium is very radiodense. Contours of the gastric and intestinal
lining is seen outlined against the white of the barium solution
CT Scans (CAT)
use a single x-ray source rotating around the body. The x-ray beam strikes a sensor
monitored by a computer. The source completes one revolution around the body every
few seconds. It then moves a short distance and repeats this process
Digital Subtraction Angiography (DSA)
, used to monitor blood flow through specific organs (brain, heart, lungs, kidneys). X-rays
are taken before and after radiopaque dye is administered, and a computer subtracts
details common to both images. Result is a high-contrast image showing the distribution
of the dye
Magnetic Resonance Imagine (MRI)
scan surrounds body with magnetic field about 3000 times as strong as Earth. Affects
protons within atomic nuclei throughout the body, which line up along the magnetic lines
of force like compass needles in Earth's field
Spiral CT Scan (Helical CT Scan)
new form of 3D imaging technology that is becoming increasingly important in clinical
settings. With spiral CT, patient is placed on platform that advances through scanner
while imaging source (usually x-rays) rotates around
Ultrasound
small transmitter contacting skin broadcasts brief, narrow burst of high-frequency sound
and then picks up the echo. The sound waves are reflected by internal structures, and a
picture (echogram) can be assembled from the pattern of echoes
The skin can regenerate effectively, even after considerable damage has
occurred, because...
... cells persist in both epithelial and connective tissue components
Germinative cell divisions replace lost...
... epidermal cells
Mesenchymal cell divisions replace lost...
... dermal cells
