CHAPTER 3: CELL ANATOMY Flashcards
Specialized structures in cells that perform specific functions.
Example: nucleus, mitochondria, ribosomes
Organelles
Jelly-like substance that holds organelles.
Cytoplasm
Also termed the plasma membrane. It is a structure that encloses the cytoplasm.
Cell membrane
What are the functions of the cell?
• Smallest units of life
• Cell metabolism and energy use
• Synthesis of molecules
• Communication
• Reproduction and inheritance
Is the outermost component of the cell. It forms a boundary between material inside the cell and outside. It acts as a selective barrier.
Cell membrane
Materials inside the cell are called what?
Intracellular
Materials outside the cell are called what?
Extracellular
The fluid inside the cell is called _______
Intracellular Fluid (ICF)
The fluid outside the cell is called ________.
Extracellular fluid (ECF)
What is the model used to describe the cell membrane structure?
Fluid-mosaic model
Add: It is proposed by Singer-Nicolson.
The cell membrane of the cell contains ________, _______, ________, and ________.
Phospholipid, cholesterol, proteins, and carbohydrates
The cell membrane of the cell forms phospholipid bilayer and it contain 2 regions. What are these?
Polar region - This part is the head which is hydrophilic - loves water
Nonpolar region - This part is the tail which is hydrophobic - fear water
Note: This phospholipid bilayer is passive (doesn’t use energy)
A phospholipid molecule has a polar head region that is _________ and a nonpolar tail region that is _________.
Hydrophilic
Hydrophobic
The _______ region of the phospholipid is exposed to water around the membrane.
Polar
The ______ region of the phospholipid is facing the interior of the membrane.
Nonpolar
The cell membrane has ____________, which allows only certain substances to pass in and out of the cell.
Selective permeability
Substances such as _______, ________, and ________ are found in higher concentrations inside the cell.
Enzymes, glycogen, and potassium
Substances such as ________, ________, and ________ are found in higher concentrations outside the cell.
Sodium, calcium, and chloride
PISO in cell membrane means
Note: This is only a technique from our professor for us to remember this part in cell.
Potassium INSIDE Sodium OUTSIDE
Some substances, like _____ and _____, can pass directly through the cell membrane’s phospholipid bilayer
Oxygen (O2) and Carbon Dioxide (CO2)
Some substances must pass through transmembrane protein channels, such as _____ through its channels.
Sodium (Na+)
The route of transport through the membrane depends in the _____,_____, and ______ of the substance.
Size, shape, and charge
Some substances require carrier molecules to transport them across the cell membrane, such as _______.
Glucose
Some substances require a ________ across the cell membrane. The vesicle must fuse with the cell membrane for transport.
Vesicular transport
What are the 2 membrane transport?
Active and Passive transport
What membrane transport does not require the cell to expend energy?
Example: CO2, O2, Steroids, Lipid, fats soluble vitamins (A, D, E, and K)
Passive Transport
Note: This is because the molecules move from higher concentration to low concentrated area.
What membrane transport does require the cell to expend energy, usually in the form of ATP?
It needs molecule or protein channel.
Example: Sodium, potassium
Active Transport
Note: This is because the molecules move from low concentration to high concentration.
Passive membrane transport mechanism include ________, _______, and _________.
Diffusion, Osmosis, and Facilitated Diffusion
Active membrane transport mechanisms include __________, _________, ________, and _________.
- Active transport
- Secondary active transport
- Endocytosis
- Exocytosis
This is the type of passive transport where there is movement of molecules down their concentration gradient from an area of higher concentration to an area of lower concentration.
Diffusion
A solution is generally composed of two major parts. What are these?
Solutes and solvent
Solutes are substances dissolved in a predominant liquid or gas, which is called what?
Solvent
This is the difference in the concentration of a solute in a solvent between two points divided by the distance between the two points.
Concentration gradient
The concentration gradient is said to be ________ when the concentration difference is large and/or the distance is small.
Steeper
Determine the sequence of diffusion:
A. Salt ions (green) move down their concentration gradient into the water.
B. When a salt crystal (green) is placed into a beaker of water, a concentration gradient exists between the salt from the salt crystal and the water that surrounds it.
C. Salt ions and water molecules are distributed evenly throughout the solution. Even though the salt ions and water molecules continue to move randomly, an equilibrium exists, and no net movement occurs because no concentration gradient exists.
B, A, C
Involves the movement of molecules across the membrane but with the aid of either channel or carrier proteins. These molecules are usually those that cannot cross due to their molecular size or chemical nature.
Facilitated diffusion
_______ soluble substances can diffuse directly through the phospholipid bilayer.
Lipid
Water-soluble substances, such as ions, can diffuse across the cell membrane only by passing through what?
Cell membrane channels
What are the two classes of cell membrane channels?
Leak channels and Gated channels
This is one of the two classes of cell membrane channels that constantly allow ions to pass through.
Leak channels
Class of cell membrane channels that limits the movement of ions across the membrane by opening and closing.
Gated channels
Is the diffusion of water (a solvent) across a selectively permeable membrane from a region of higher water concentration to one of lower water concentration.
Osmosis
Three requirements for osmosis to happen:
- Solvent - water
- Selectively permeable membrane (SPM)
- Higher to lower concentration
Osmosis exerts a pressure, a termed __________, which is the force required to prevent movement of water across cell membrane.
Osmotic pressure
Osmotic pressure depends on the difference of ___________ inside a cell relative to outside the cell.
Solution concentration
What solution has a lower concentration of solutes and a higher concentration of water relative to the cytoplasm of the cell. The water goes inside the cell
The solution has less tone, or osmotic pressure, than the cell.
Hypotonic
Note: Water is attracted to salt, that’s the reason why the water goes inside the cell since there is higher concentration of solute inside.
In hypotonic, water moves by osmosis into the cell, causing it to swell.
If the cell swells enough, it can rupture, a process called _________
Lysis
This solution has the same solute concentrations inside and outside the cell. The cell will neither shrink nor swell. No movement of water.
Isotonic
Note: Iso means equal
The cytoplasm of the cell in this solution has a lower solute concentration and higher water concentration than the surrounding solution. The water goes outside the cell.
Hypertonic solution
Water moves by osmosis from the cell into the hypertonic solution, resulting in what?
Cell shrinkage or crenation
In carrier-mediated transport
Some water-soluble, electrically charged or large sized particles cannot enter or leave through the cell membrane by diffusion. These substances include _______, ______, and some __________ produced by the cell.
Amino acids, glucose, some polar molecules
These are proteins within the cell membrane involved in carrier-mediated transport.
Carrier molecules
Carrier-mediated transport mechanisms includes these two. What are these?
Facilitated diffusion and Active transport
Note:
Facilitated diffusion does not require ATP for energy while Active transport does require ATP for transport.
Is a carrier-mediated transport process that moves substances across the cell membrane from an area of higher concentration to an area of lower concentration of that substance.
Facilitated diffusion
In facilitated diffusion,
Because the movement is with the concentration gradient, metabolic energy in the form of ATP is ________
A. required
B. not required
B. not required
Is a carrier- mediated process, requiring ATP, that moves substances across the cell membrane from regions of lower concentration to those of higher concentration against a concentration gradient.
Active transport
_____________ processes accumulate necessary substances on one side of the cell membrane at concentrations many times greater than those on the other side.
Active transport
A major example of active transport is the action of the _________ present in cell membranes. This moves Na+ out of cells and K+ into cells.
The result is a higher concentration of Na+ outside cells and a higher concentration of K+ inside cells.
Sodium-Potassium Pump
Uses the energy provided by a concentration gradient established by the active transport of one substance, such as Na+ to transport other substances.
No additional energy is required above the energy provided by the initial active transport pump.
Secondary active transport
In secondary active transport,
What do you call it when the diffusing substance moves in the same direction as the initial active transported substance?
Cotransport
In secondary active transport,
What do you call it when the diffusing substance moves in a direction opposite to that of the initial active transported substance?
Countertransport
This is a process that brings materials into cell using vesicles.
Endocytosis
A type of endocytosis that occurs when a specific substance binds to the receptor molecule and is transported into the cell.
Example: Virus
Receptor-mediated endocytosis
This is often used for endocytosis when solid particles are ingested. This is the most common.
The word means cell eating
Example: WBC eating bacteria
Phagocytosis
This has much smaller vesicles formed, and they contain liquid rather than solid particles.
The word means cell drinking
Pinocytosis
What are the 3 types of endocytosis?
• Receptor-mediated endocytosis
• Phagocytosis
• Pinocytosis
This is the process where the vesicles move to the cell membrane and fuse, ultimately releasing the material outside the cell.
Example: Secretion of digestive enzymes
Exocytosis
Exocytosis involves the use of membrane bound sacs called _______ that accumulate materials for release from the cell.
Secretory vesicles
What are the three major part of the cell?
Nucleus
Cytoplasm
Cell membrane
What is the sausage like organelle in the cell? It is also known as the powerhouse of the cell.
Mitochondria
What is a large organelle usually located near the center of the cell?
Nucleus
The nucleus is bounded by a _______, which consists of outer and inner membranes with a narrow space between them.
Nuclear envelope
What does the nuclear membrane contains which materials can pass into or out of the nucleus?
Nuclear pores
DNA stands for
Deoxyribonucleic acid
The nuclei of human cells contain how many pairs of chromosomes which consists of DNA and proteins?
23 pairs
Small proteins that is responsible for protein synthesis
Ribosomes
What is the covering of the nucleus that has an outer and inner membrane?
Nuclear envelope
Is a term used to describe the physical structure of DNA.
Double helix
What part of the nucleus produces ribosomes?
Nucleolus
What do you call it when ribosomes attached to other organelles such as the endoplasmic reticulum?
Rough Endoplasmic reticulum
Ribosomes that are not attached to any other organelle are called what?
Free ribosomes
Endoplasmic reticulum that doesn’t have any ribosomes attached are called
Smooth endoplasmic reticulum
What is the correct order of ribosome production?
A. The small and large ribosomal subunits leave the nucleolus and the nucleus through nuclear pores.
B. Ribosomal proteins, produced in the cytoplasm, are transported through nuclear pores into the nucleolus.
C. rRNA (ribosomal RNA), most of which is produced in the nucleolus, is assembled with ribosomal proteins to form small and large ribosomal subunits.
D. The small and large subunits, now in the cytoplasm, combine with each other and with mRNA during protein synthesis.
B, C, A, D
Since the smooth endoplasmic reticulum doesn’t have ribosomes attached to it, what is the function of this organelle?
Site for lipid synthesis
Note: It also store calcium which is necessary for muscle contraction and deposition of bones (bone formation)
Is a series of membranes forming sacs and tubules that extend from the outer nuclear membrane into the cytoplasm.
Endoplasmic Reticulum (ER)
Consists of closely packed stacks of curved, membrane-bound sacs. It collects, modifies, packages, and distributes proteins and lipids manufactured by the ER.
Golgi Apparatus
Note: This is like the post office
Golgi Apparatus is also called as
Golgi complex
This plays an important role in moving molecules outside of the cell, through a process called exocytosis.
Secretory vesicles
This is a cellular process in which substances are brought into the cell.
Endocytosis
These are membrane-bound vesicles formed from the Golgi Apparatus. It contains a variety of enzymes that function as intracellular digestive systems. Its main function is digestion and waste removal.
Lysosomes
This is a process by which a phagocyte (a type of white blood cell) surrounds and destroys foreign substances (such as bacteria) and removes dead cells.
Phagocytosis
These are small, membrane-bound vesicles containing enzymes that break down fatty acids, amino acids, and hydrogen peroxide (H2O2).
Peroxisomes
Hydrogen peroxide is a by-product of fatty acid and amino acid breakdown and can be toxic to a cell but the enzymes in peroxisomes break it down into what so that it will not be toxic anymore?
Water and oxygen (H2O + O2)
Singular of mitochondria
Mitochondrion
ATP Stands for
Adenosine Triphosphate
ADP Stands for
Adenosine Diphosphate
Are small organelles responsible for producing considerable amounts of ATP by aerobic (with O2) metabolism.
Mitochondria
Mitochondria’s outer membrane have a smooth contour, but the inner membranes have numerous folds. What do you call those folds?
Cristae
The material within the inner membrane of the mitochondria that contains enzymes and mitochondrial DNA (mtDNA) is called
Mitochondrial matrix
This part of the cell gives an internal framework to the cell. It consists of protein structures that support the cell, hold organelles in place, and enable the cell to change shape.
Cytoskeleton
What are the 3 protein structures that are an example of cytoskeleton?
- Microtubules
- Microfilaments
- Intermediate filaments
During most of a cell’s life, the chromosomes are loosely coiled and collectively called
Chromatin
What do you call the cytoskeleton that are hollow structures formed from protein subunits?
Microtubules
The microtubules perform a variety of roles, including helping to support the cytoplasm of cells, assisting in cell division, and forming essential components of certain organelles, such as ______ and ________.
Cilia and flagella
What do you call the cytoskeleton that are small fibrils formed from protein subunits that structurally support the cytoplasm, determining cell shape?
Microfilaments
Note: Some microfilaments are involved in cell movement. In muscle cells, it enable the cells to shorten or contract.
What do you call the cytoskeleton that are fibrils formed from protein subunits that are smaller in diameter than microtubules but larger in diameter than microfilaments.
Intermediate filaments
A specific type of intermediate filament is _______, a protein associated with skin cells.
Add: Intermediate filament helps in providing mechanical support to the cell.
Keratin
The ________ is a specialized area of
cytoplasm close to the nucleus where
microtubule formation occurs.
Centrosome
The centrosome contains two centrioles, which are normally oriented _________ to each other.
Perpendicular
The ___________ is involved in the process of mitosis. Each of these is a small, cylindrical organelle composed of microtubules.
Centrioles
_______ are cylindrical structures that extend from the cell and are composed of microtubules. This project from the surface of certain cells. They are responsible for the movement of materials over the top of cells, such as mucus.
Cilia
These have a structure similar to that of cilia but are much longer, and they usually occur only one per cell.
Flagella
Sperm cells each have one ________, which
propels the sperm cell.
flagellum
_______ are specialized extensions of the cell membrane that are supported by microfilaments.
They do not actively move as cilia and flagella do.
Microvilli
Microvilli are numerous on cells that have them and they increase the _________ of those cells.
Surface area
Microvilli are abundant on the surface of cells that line the intestine, kidney, and other areas in which ________ is an important function.
Absorption
A ______________ are determined by the type of proteins produced.
The proteins produced are in turn determined by the ____________ in the nucleus.
Information in DNA provides the cell with a ____ for its cellular processes.
cell’s characteristics
genetic information
code
DNA contains the information that directs protein synthesis; a process called ________________.
gene expression
A DNA molecule consists of ___________ joined together to form two nucleotide strands.
nucleotides
In DNA, The two nucleotide strands are connected and resemble a ________ that is twisted around its long axis.
ladder
Each nucleotide consists of these 3. What are these?
5-carbon sugar (Deoxyribose)
A phosphate group
Nitrogenous bases (adenine (A), thymine (T), cytosine (C), and guanine (G))
Each nucleotide on one DNA strand has a specific bonding pattern to another nucleotide on the _________ strand.
A. same
B. opposite
B. opposite
A _______ is a sequence of nucleotides that provides a chemical set of instructions for making a specific protein.
gene
______________, which is protein synthesis, involves transcription and translation.
Gene expression
This involves copying DNA into messenger RNA. It takes place in the nucleus of the cell.
Transcription
This involves messenger RNA being used to produce a protein.
Translation
During growth and development, This occurs to increase the number of cells or replace damaged or dying ones.
This also involves a cell cycle.
Cell division
The cell cycle includes two major phases: a nondividing phase, called _______, and a cell dividing phase, termed ________.
Interphase
Mitosis
A cell spends most of its life cycle in this phase performing its normal functions.
During this, the DNA (located in
chromosomes in the cell’s nucleus) is replicated.
Interphase
During cell cycle,
Replication of DNA gives two identical _________ joined at a centromere; both form one chromosome.
chromatids
Individuals having two X chromosomes (XX) are what?
Female
Individuals having one X chromosome and one Y chromosome (XY) are what?
Male
Each human cell (except sperm and egg) contains how many pairs of chromosomes and its total.
23 pairs
46 in total
This involves the formation of 2 daughter cells from a single-parent cell. It has four phases.
Mitosis
Mitosis is divided into 4 phases. What are these?
Remember PMAT
Prophase, Metaphase, Anaphase, and Telophase
This is the phase in mitosis where the chromatin condenses to form visible chromosomes.
Microtubules, termed spindle fibers, form to assist in breaking the centromere between the chromatids and move the chromosomes to opposite sides of the cell.
The nuclear membrane dissolves.
Prophase
This is the phase in mitosis where the chromosomes align near the center of the cell.
The movement of the chromosomes is regulated by the attached spindle fibers.
Metaphase
Phase in mitosis where
At the beginning of this phase, the chromatids separate and each chromatid is called a chromosome.
Each of the two sets of 46 chromosomes is moved by the spindle fibers toward the centriole at one of the poles of the cell.
At the end of this phase, each set of
chromosomes have reached the opposite pole of the cell, and the cytoplasm begins to divide.
Anaphase
Phase in mitosis where
During this phase, the chromosomes in each of the daughter cells become organized to form two separate nuclei, one in each newly formed daughter cell.
The chromosomes begin to unravel and resemble the genetic material during interphase.
Following this phase, cytoplasm division is completed, and two separate daughter cells are produced.
Telophase
In differentiation,
A ______ and an _______ unite to form a single cell, and then a great number of mitotic divisions occur to give the trillions of cells of the body.
sperm cell and an oocyte
Note: oocyte is a developing egg
The process by which cells develop with specialized structures and functions is called
Differentiation
During differentiation of a cell, some portions of DNA are _____, but others are ______.
active and inactive
This is termed programmed cell death, and is a normal process by which cell numbers within various tissues are adjusted and controlled.
Apoptosis
In the developing fetus, apoptosis removes ______, such as cells between the developing fingers and toes.
extra tissue
In some adult tissues, apoptosis eliminates excess cells to maintain a _________ of cells within the tissue.
constant number
In Cellular Aspects of Aging
There are various causes for cellular aging. What are these?
- Existence of a cellular clock
- Presence of death genes
- DNA damage
- Formation of free radicals
- Mitochondrial damage
What do you call the abnormal proliferation of cells?
They are due to problems occurring in the cell cycle.
Tumors
Tumors can be ____ and _______.
benign and malignant (cancer)
Malignant tumors can spread by a process, termed what?
Metastasis
