Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
169 Cards in this Set
- Front
- Back
|
Cells
|
Smallest units that perform all vital physiological functions
|
|
|
Atoms
|
Building blocks of molecules
|
|
|
Cytology
|
Study of the structure and function of cells
|
|
|
Somatic cells
|
Include the other cells in the human body
|
|
|
The human body contains _______ classes of cells. (#)
|
2
|
|
|
What are the two classes of cells in the human body?
|
Somatic and sex cells
|
|
|
What is another name for somatic cells?
|
Germ cells
|
|
|
There are more than _________ cells in the human body. (#)
|
100 trillion
|
|
|
Plasma membrane
|
Barrier between cell and external environment
|
|
|
Intracellular fluid (ICF)
|
Fluid inside cell
|
|
|
Extracellular fluid (ECF)
|
Fluid outside cell
|
|
|
Plasmalemma
|
Plasma membrane; forms the outer boundary of the cell
|
|
|
Cell membrane
|
Physical barrier that separates the inside of the cell from the surrounding extracellular fluid
|
|
|
Differences in and outside of the cell must be maintained to preserve _______.
|
Homeostasis
|
|
|
The cell membrane controls the entry of _______ and _______.
|
Ions and nutrients
|
|
|
What three structures does the cell membrane contain?
|
Lipids, proteins, and carbohydrates
|
|
|
What forms most of the cell membrane surface?
|
Lipids
|
|
|
Why is the cell membrane called a phospholipid bilayer?
|
The phospholipids form two distinct layers
|
|
|
________ and ___________ cannot enter the interior of a micelle.
|
Ions and water-soluble compounds
|
|
|
What is the importance of cytoplasm being isolated from the surrounding fluid environment?
|
Cytoplasm composition is different than extracellular fluid and the cell can't survive if differences are eliminated
|
|
|
Phospholipids
|
Basic structure of membrane
|
|
|
Cholesterol
|
Adds fluidity to membrane and decreases permeability
|
|
|
Are there more integral proteins or peripheral proteins?
|
Integral proteins
|
|
|
Peripheral proteins
|
Bound to the inner and outer surfaces of membrane
|
|
|
What are the ways membrane proteins may function? (6)
|
Anchoring proteins, identifiers, enzymes, receptors, carriers, or channels
|
|
|
Anchoring proteins
|
Membrane proteins that may attach the cell membrane to other structures to stabilize its position
|
|
|
Recognition proteins
|
Identifier proteins that recognize other cells as normal or abnormal on the basis of the presence or absence of characteristic recognition proteins
|
|
|
Many important recognition proteins are __________.
|
Glycoproteins
|
|
|
Enzymes may be _______ or ________ proteins.
|
Integral or peripheral
|
|
|
Receptor proteins
|
Proteins that are sensitive to the presence of specific molecules
|
|
|
Carrier proteins
|
Proteins that bind solutes and transport them across the cell membrane
|
|
|
Channels
|
Central pore that forms a passageway that permits the movement of water and other solutes across the cell membrane
|
|
|
What does not dissolve in lipids?
|
Ions
|
|
|
What are the two major kinds of channels in membrane proteins?
|
Leak channels and gated channels
|
|
|
Leak channels
|
Permit water and ion movement at all times
|
|
|
Gated channels
|
Can open or close to regulate ion passage
|
|
|
Amphipathic
|
Have hydrophilic and hydrophobic parts
|
|
|
_______ are covalently bound to membrane lipids or proteins
|
Carbohydrates
|
|
|
Carbohydrates account for roughly what percentage of the cell membrane?
|
3%
|
|
|
Calyx
|
Cup
|
|
|
Cytoplasm
|
General term for material located inside the cell membrane and outside the membrane surrounding the nucleus
|
|
|
Cytoplasm contains many more __________ than does the extracellular fluid.
|
Proteins
|
|
|
What are the two major subdivisions of cytoplasm?
|
Cytosol (intracellular fluid) and organelles
|
|
|
Cytosol
|
Contains dissolved nutrients, ions, soluble and insoluble proteins, and waste products
|
|
|
Organelles
|
Structures that perform specific functions within the cell
|
|
|
The cytosol contains a relatively high concentration of ______ and a low concentration of ________.
|
Potassium ions; sodium concentration
|
|
|
Extracellular fluid contains a high concentration of ________ and a low concentration of ________.
|
Sodium ions; potassium concentration
|
|
|
What are the two categories of organelles?
|
Nonmembranous organelles and membranous organelles
|
|
|
What are the cell's nonmembranous organelles? (6)
|
Cytoskeleton, microvilli, centrioles, cilia, flagella, and ribosomes
|
|
|
Membranous organelles
|
Surrounded by lipid membranes that isolate them from the cytosol
|
|
|
What are the membranous organelles? (6)
|
Mitochondria, endoplasmic reticulum, golgi apparatus, lysosomes, peroxisomes, and the nucleus
|
|
|
Nucleus
|
Control center of cellular operations
|
|
|
Nucleolus
|
Site of rRNA synthesis
|
|
|
What is the function of the nucleus?
|
To transmit and express genetic information in the form of DNA
|
|
|
How does the nucleus determine the structural and functional characteristics of the cell?
|
By controlling which proteins are synthesized and in what amounts
|
|
|
Nuclear envelope
|
Surrounds the nucleus and separates it from the cytosol
|
|
|
________ is a double-layer membrane separated by a narrow perinuclear space.
|
Nuclear envelope
|
|
|
Chemical communication between the nucleus and cytosol occurs through _________.
|
Nuclear pores
|
|
|
Nucleoplasm
|
Refers to the fluid contents of the nucleus
|
|
|
DNA strands are located in complex structures known as _________.
|
Chromosomes
|
|
|
Endoplasmic Reticulum (ER)
|
Network of intracellular membranes that is connected to the nuclear envelope surrounding the nucleus
|
|
|
What are the two appearances of ER?
|
Rough ER and smooth ER
|
|
|
What are the main differences between rough ER and smooth ER?
|
Rough ER contains ribosomes, and smooth ER does not.
|
|
|
Cisternae
|
Round chambers that act as a reservoir for water
|
|
|
The endoplasmic reticulum forms what 3 things?
|
Hollow tubes, flattened sheets, and cisternae
|
|
|
What are the four major functions of the endoplasmic reticulum?
|
Synthesis, storage, transport, and detoxification
|
|
|
What does rough endoplasmic reticulum function in doing?
|
In synthesis of proteins to be packaged into vesicles
|
|
|
What does smooth endoplasmic reticulum function in doing?
|
In lipid synthesis, including triglycerides and steroids
|
|
|
Golgi apparatus
|
Consists of 5-6 flattened membrane discs that communicate with the ER to help in movement of various synthesized chemicals
|
|
|
Saccules
|
Flattened membrane discs contained in the Golgi apparatus
|
|
|
What are the three major functions of the Golgi apparatus?
|
Synthesis and packaging secretions, renewal or modification of cell membrane, and packaging special enzymes
|
|
|
Mitochondria
|
Small organelles where ATP is created by means of the Krebs cycle
|
|
|
Cristae
|
Folds located in the inner membrane of the mitochondria
|
|
|
Matrix
|
Surface area exposed to the fluid contents of the mitrochondria
|
|
|
Metabolic enzymes in the _______ perform the reactions that provide energy for cellular function.
|
Matrix
|
|
|
Where do most of the cellular activities that require energy occur in?
|
The surrounding cytoplasm
|
|
|
Energy is stored and transferred in the form of _________.
|
High-energy bonds
|
|
|
What kind of group do high-energy bonds generally attach to?
|
Phosphate group
|
|
|
What is the most important high-energy compound?
|
Adenosine triphosphate (ATP)
|
|
|
_______ break the high-energy bond under controlled conditions.
|
Living cells
|
|
|
In the mitochondria, living cells break the high-energy bond under controlled conditions. What does ATP become? (2 things)
|
ADP and phosphate
|
|
|
Most cells generate ATP and other high-energy compounds through the breakdown of _________, esp. glucose.
|
Carbohydrates
|
|
|
Lysosomes
|
Vesicles filled with digestive enzymes
|
|
|
Lysosomes are produced where?
|
Golgi apparatus
|
|
|
Primary lysosomes contain _______.
|
Inactive enzymes
|
|
|
When does enzyme activation occur?
|
When the lysosome fuses with the membranes of damaged organelles
|
|
|
What is the function of lysosomes?
|
To contain enzymes that degrade cellular or extracellular debris
|
|
|
What are the two types of lysosomes?
|
Endocytosis and phagocytosis
|
|
|
___________ perform essential cleanup and recycling functions inside the cell.
|
Lysosomes
|
|
|
Peroxisomes
|
Organelles that are smaller than lysosomes and carry a different group of enzymes, usu. peroxide-based enzymes
|
|
|
What is the function of peroxisomes?
|
To degrade certain waste molecules
|
|
|
Ribosomes
|
Organelles that manufacture proteins using information provided by the DNA of the nucleus
|
|
|
The number of ribosomes within a particular cell varies depending on _________.
|
The type of cell
|
|
|
A functional ribosome consists of _____ subunits and are normally separate and distinct.
|
2; large and heavy or light and small
|
|
|
What must happen before protein synthesis can begin?
|
A light and heavy ribosomal subunit must join together with a strand of mRNA to create a functional ribosome
|
|
|
What are the two major types of functional ribosomes?
|
Free ribosomes and fixed ribosomes
|
|
|
Where are the free ribosomes located?
|
Scattered throughout the cytoplasm
|
|
|
Where are the fixed ribosomes located?
|
Attached to the endoplasmic reticulum
|
|
|
Vaults
|
Barrel-shaped organelles that may function in transport of molecules between nucleus and cytoplasm
|
|
|
Centrioles
|
Paired cylindrical structures that function in development of the mitotic spindle
|
|
|
Cytoskeleton
|
An internal protein framework that gives the cytoplasm strength and flexibility; the "backbone" of the cell
|
|
|
What are the four major components of the cytoskeleton?
|
Microfilaments, intermediate filaments, thick filaments, and microtubules
|
|
|
Thick filaments only appear in _________ cells.
|
Muscle
|
|
|
What is the most common type of microfilament?
|
Actin
|
|
|
What are the functions of microfilaments?
|
Separation of cytoplasm during cell division and structural support for cell projections
|
|
|
Microvilli
|
Small, finger shaped projections of the cell membrane that greatly increase the surface area of the cell exposed to the extracellular environment
|
|
|
Cilia
|
Appear as 9 pairs of microtubles surrounding a central pair (9+2 structure)
|
|
|
Fagella
|
Whip-like structure that allows for moving upstream (sperm)
|
|
|
The _______ cell is the only cell that has a flagellum in humans.
|
Sperm
|
|
|
What are the functions of the microtubles?
|
Mitotic spindle and major component of cilia and flagella
|
|
|
Where can you find microtubles in the body? (3 places)
|
Respiratory tract, oviduct, and sperm
|
|
|
Cell adhesion molecules
|
Send signals from cell to cell
|
|
|
Tight junctions
|
Cell adhesion molecule that causes transepithelial transport
|
|
|
Desmosomes
|
Cell adhesion molecule that binds cells together for strength
|
|
|
Gap junctions
|
Composed of membrane proteins that allow for ions and molecules moving between cells act as a signal of electricity
|
|
|
Chromosomes
|
Area where DNA is stored
|
|
|
Histones
|
Special proteins where DNA strands are bound
|
|
|
DNA strands coil around _________ allowing a great deal of DNA to be packaged in a small space.
|
Histones
|
|
|
Somatic cells
|
All cells other than sex cells
|
|
|
How many chromosomes do the nuclei of somatic cells contain?
|
23 chromosomes
|
|
|
One of each pair of chromosomes are derived from ________.
|
Parents
|
|
|
Nucleotide structure
|
5-carbon carbohydrate that makes up chromosomes
|
|
|
What are the two kinds of messenger molecules?
|
cAMP and cGMP
|
|
|
What are the 3 kinds of pyrimidines?
|
Cytosine, thymine, and uracil
|
|
|
What are the 2 kinds of purines?
|
Adenine and guanine
|
|
|
Nucleic acids are polymers of ________.
|
Nucleotides
|
|
|
What are the 2 kinds of nucleic acids?
|
DNA and RNA
|
|
|
What carbohydrate does DNA contain?
|
Deoxyribose
|
|
|
The DNA of the nucleus controls the cell by means of what?
|
Protein synthesis
|
|
|
What are the 2 levels of DNA control?
|
Direct control and indirect control
|
|
|
The nucleus can accelerate the rate of ________ by increasing the number of needed enzymes in the cytoplasm.
|
Glycolysis
|
|
|
Protein synthesis
|
The role of the genetic code by means of transcription and translation
|
|
|
What are the steps of protein synthesis? (3 steps)
|
1. DNA ----- transcribed -----> mRNA
2. mRNA = nucleus -----> cytoplasm 3. mRNA ------ translated ------> cytoplasm to proteins |
|
|
Gene
|
Portion of DNA with code
|
|
|
Triplet
|
Nucleotide sequence that codes for particular amino acid
|
|
|
Triplet is transcribed into ______.
|
Codon
|
|
|
______ is transcribed into codon.
|
Triplet
|
|
|
How many amino acids are there?
|
20
|
|
|
Each codon codes for how many amino acids?
|
1
|
|
|
One amino acid can be coded by how many codons?
|
1+
|
|
|
What is the role of RNA polymerase?
|
To help with DNA's process of uncoiling (DNA sequencing) and to speed up processes
|
|
|
A DNA molecule consists of a pair of DNA strands held together by what?
|
Hydrogen bonding between complementary nitrogenous bases
|
|
|
When does DNA replication begin?
|
When various enzymes unwind and disrupt weak bonds between the nitrogenous bases
|
|
|
Liga
|
To tie
|
|
|
Ligases
|
Enzymes that link nucleotides together
|
|
|
Spliced exons
|
Contains code in processed mRNA
|
|
|
5' CAP
|
Necessary for initiation of translation of mRNA
|
|
|
3' Poly A tail
|
Protects mRNA from degration
|
|
|
Translation requires what 3 things?
|
mRNa, tRNA, and rRNA
|
|
|
Where does translation occur?
|
In the cytoplasm
|
|
|
What are the two kinds of tRNA?
|
Charged tRNA and free tRNA
|
|
|
What's the difference between charged tRNA and free tRNA?
|
Charged tRNA is amino-acid-bound, and free tRNA is not
|
|
|
What are the 2 tRNA binding sites?
|
P site and A site
|
|
|
What is the difference between the P site and the A site?
|
The P site holds tRNA with the last amino acid added to the polypeptide chain, and the A site hols tRNA with next amino acid to be added
|
|
|
The ultimate destination of translation depends on _________.
|
Leader sequence
|
|
|
Mitosis
|
Process that separates duplicated chromosomes of the original cell into two identical nuclei
|
|
|
________ specifically refers to the division and the duplication of the nucleus of the cell.
|
Mitosis
|
|
|
_______ is the reproduction of the nucleus of the cell.
|
Mitosis
|
|
|
_________ is the reproduction of the cell itself.
|
Cytokinesis
|
|
|
Cytokinesis
|
Division of cytoplasm to form new distinct cells
|
|
|
What are the four stages of mitosis?
|
Prophase, metaphase, anaphase, and telophase
|
|
|
Prophase
|
Phase of mitosis that begins when the chromosomes coil so tightly that they become visible as individual structures
|
|
|
Metaphase
|
Phase of mitosis that begins after the degeneration of the nuclear evelope
|
|
|
Metaphase ends when _________.
|
Chromatids are aligned
|
|
|
Anaphase
|
Phase of mitosis that begins when the chromatid pair splits
|
|
|
Anaphase ends when ________.
|
Daughter chromosomes arrive near the centrioles
|
|
|
Telophase
|
Phase of mitosis that begins when each cell prepares to return to the interphase state
|
|
|
_______ marks the end of mitosis.
|
Telophase
|
|
|
_______ is the formation of two new cells; ______ is the formation of two new nuclei.
|
Cytokinesis; mitosis
|
