Cell Physiology And CVS Physiology Flashcards
What is physiology,pathophysiology
What are the principles of the cell theory
Name five characteristics of prokaryotic and eukaryotic cells
Physics Biology = Physiology
●Definition: Physiology is the branch of medical science that deals with the study of all the NORMAL functions of the human body.
● vital processes or functions of living of the body.
●Pathophysiology: How physiological processes are altered in disease or injury.
1.All living things are made of cells
2.●Smallest living unit of structure and function of all organisms is the cell
3.All cells arise from preexisting cells
●this principle discarded the idea of spontaneous generation
●First cell type on earth ●Cell type of Bacteria ●No membrane bound nucleus ●Nucleoid = region of DNA concentration ●Organelles not bound by membranes
Eukaryotic:
Nucleus bound by membrane
●Include fungi, protists, plant, and animal cells
●Possess many organelles
What is chloroplast as a part of the plant cell and peroxisome as a part of the animal cell
Organelle= “little organ”
●Found only inside eukaryotic cells
●All the stuff in between the organelles is cytosol
●Everything in a cell except the nucleus is cytoplasm
True or false
A chloroplast is an organelle within the cells of plants and certain algae that is the site of photosynthesis, which is the process by which energy from the Sun is converted into chemical energy for growth.
Peroxisomes are organelles that sequester diverse oxidative reactions and play important roles in metabolism, reactive oxygen species detoxification, and signaling. Oxidative pathways housed in peroxisomes include fatty acid β-oxidation, which contributes to embryogenesis, seedling growth, and stomatal opening.
Peroxisomes are oxidative molecules
Describe a nucleus
What is a nuclear pore,nucleoplasm,chromatin and chromosome
Control center of the cell ●Contains DNA ●Surrounded by a double membrane ●Usually the easiest organelle to see under a microscope ●Usually one per cell
The parts of the nucleus are the nuclear pores(A nuclear pore is a part of a large complex of proteins, known as a nuclear pore complex that spans the nuclear envelope, which is the double membrane surrounding the eukaryotic cell nucleus. )nuclear envelope and the nucleolus
Or
nuclear membrane, called the nuclear envelope, nucleoplasm, nucleolus, and chromosomes. Nucleoplasm, also called karyoplasm, is the matrix present inside the nucleus.
Chromatin refers to a mixture of DNA and proteins that form the chromosomes found in the cells of humans and other higher organisms.
The DNA is packaged by special proteins called histones to form chromatin. The chromatin further condenses to form chromosomes.
What are the functions of the cytoskeleton
Name the three types of filaments of the cytoskeleton
What is the function of the endoplasmic reticulum
Acts as skeleton and muscle
●Provides shape and structure
●Helps move organelles around the cell
●Made of three types of filaments
Microtubules(Despite the “micro” in their name, microtubules are the largest of the three types of cytoskeletal fibers .made up of tubulin proteins),actin filaments or micro filaments(Because of its relationship to myosin, actin is involved in many cellular events requiring motion Actin filaments have directionality, meaning that they have two structurally different ends. They are the narrowest filaments),intermediate filaments(One protein that forms intermediate filaments is keratin, )
●Connected to nuclear membrane
●Highway of the cell
●Rough ER: studded with ribosomes; it makes proteins
●Smooth ER: no ribosomes; it makes lipids
What is the function of ribosomes and Golgi apparatus,lysosomes,mitochondria ,chloroplast,cell wall,vacuole,centrioles
Site of protein synthesis
●Found attached to rough ER or floating free in cytosol
●Produced in a part of the nucleus called the nucleolus
Golgi:
Looks like a stack of plates
●Stores, modifies and packages proteins
●Molecules transported to and from the Golgi by means of vesicles
Garbage disposal of the cell
●Contain digestive enzymes that break down wastes
Powerhouse of the cell”
●Cellular respiration occurs here to release energy for the cell to use
●Bound by a double membrane
●Has its own strand of DNA
Found only in plant cells
●Contains the green pigment chlorophyll
●Site of food (glucose) production
●Bound by a double membrane
Cell wall: Found in plant and bacterial cells
●Rigid, protective barrier
●Located outside of the cell membrane
●Made of cellulose (fiber)
Large central vacuole usually in plant cells
●Many smaller vacuoles in animal cells
●Storage container for water, food, enzymes, wastes, pigments, etc.
Centriole
●Aids in cell division
●Usually found in animal cells
●Made of microtubules
What is the cell membrane and state it’s functions
What does the fluid-mosaic model state
What are phospholipids
Also called Plasma Membrane
●surrounds the cell and functions as an interface between the living interior (intracellular space) of the cell and the nonliving exterior (extracellular space).
●The cell membrane separates the intracellular environment (ICF) from the extracellular environment (ECF).
●It regulates the movement of molecules into and out of the cell.
The cell membrane is one of the great multi-taskers of biology. It provides structure for the cell, protects cytosolic contents from the environment, and allows cells to act as specialized units. A membrane is the cell’s interface with the rest of the world - it’s gatekeeper, if you will. This phospholipid bilayer determines what molecules can move into or out of the cell, a
The fluid-mosaic model states that cell membranes are phospholipid bilayers with protein molecules embedded in the bilayer.
●Phospholipids: Phospholipids mean it contains a phosphate group as the head and the tail is made up of lipid or glycerol, (two fatty acids).
●The phosphate group is polar (hydrophilic- loves water), enabling it to interact with water. The fatty acid tails are nonpolar (hydrophobic- hates water) and do not interact with water.
What are the two main types of transport in the cell membrane
Explain them each (define them and how they happen)
BASIC CONCEPT OF TRANSPORT IN BIOLOGICAL SYSTEM
●Types of transport in the cell membrane
●There are two major ways that the molecules move through the cell membrane
●Passive
● does not make use of energy in the form of ATP (Adenosine Triphosphate).
●Active transport
● makes use of energy in the form of ATP (Adenosine Triphosphate).
In Passive transport molecules or ions cross the cell membrane by
● moving down a concentration or electrochemical gradient (down hill).
●In active transport molecules or ions cross the cell membrane by
●moving against their concentration or electrochemical gradient (up hill).
What is the difference between transport and exchange surfaces and give an example to explain
What is diffusion
What is osmosis and give examples
Differences between osmosis and diffusion
Transport
Organisms need to be able to move materials (such as respiratory gases, nutrients, waste products and heat) both into and out of, and within, themselves - that is called transport.
Exchange Surfaces
Specialized exchange surfaces are biological structures whose features are such that they permit the highly efficient transfer of materials e.g. respiratory gases, across them (i.e. across the exchange surfaces) via mechanisms such as diffusion or active transport.
Example:
All living things need to breathe (perform respiration) so movement of respiratory gases, e.g. accepting oxygen into the organism, is an important part of transport in biology.
Although many microorganisms accept oxygen directly through their cell membrane, organisms whose surface-area:volume ratio is larger, e.g. mammals, need specialized exchange surfaces through which to receive oxygen and release carbon dioxide. Such exchange surfaces are often part of organs, e.g. within the lungs of birds and mammals and within the gills of fish.
Example of passive mechanisms include diffusion(simple diffusion and facilitated diffusion ) and osmosis,filtration
Osmosis
The process of moving of solvent particles across a semipermeable membrane from a dilute solution into a concentrated solution to equalize concentration. The complete process does not require energy in order to take place.
For example, the absorption of water molecules from the soil through the roots of the plant.
Diffusion
The process of moving particles from a region of higher concentration to the region of lower concentration until equilibrium is reached. Simple diffusion does not require energy in order to take place; however, facilitated diffusion requires ATP.
An example of diffusion of the perfume sprays into the air by spreading the aroma.
Osmosis
It is limited only to the liquid medium. Diffusion -Occurs in liquid, gas and even solids.
Osmosis-Requires a semipermeable membrane.
Diffusion-Does not require a semipermeable membrane.
Osmosis-Depends on the number of solute particles dissolved in the solvent
Diffusion:. Depends on the presence of other particles.
Requires water for the movement of particles. Does not require water for the movement of particles.
Only the solvent molecules can diffuse. Both the molecules of solute and solvent can diffuse.
The flow of particles occurs only in one direction. The flow of particles occurs in all the directions.
The entire process can either be stopped or reversed by applying additional pressure on the solution side. This process can neither be stopped nor reversed.
What is facilitated diffusion
Give examples of passive transport
Give five differences between active and passive transport
Name molecules transported by active transport
State and define the types of active transport
What is exocytosis,Endocytosis
Facilitated Diffusion
Facilitated diffusion is the passive transportation of ions or molecules across the cell membrane through specific transmembrane integral proteins. The molecules, which are large and insoluble require a carrier substance for their transportation through the plasma membrane. This process does not require any cellular or external energy.
Examples Of Passive Transport
Following are some of the examples of passive transport:
Ethanol enters our body and hits the bloodstream. This happens because the ethanol molecules undergo simple diffusion and pass through the cell membrane without any external energy.
Reabsorption of nutrients by the intestines by separating them from the solid waste and transporting the nutrients through the intestinal membrane into the bloodstream.
When a raisin is soaked in water the water moves inside the raisin by the process of osmosis and it swells.
Active Transport
Requires cellular energy.
Passive Transport -Does not require cellular energy.
Active-It circulates from a region of lower concentration to a region of higher concentration(remember the person pushing a stone up a hill so it’s hard to push unless you put in more energy)
Passive:It circulates from a region of higher concentration to a region of lower concentration(person pushing stone down a hill)
Active-Required for the transportation of all the molecules such as proteins, large cells, complex sugars, ions, etc. passive-Required for the transportation of all soluble molecules, including oxygen, water, carbon dioxide, lipids, sex hormones, etc.
Active-It transports various molecules in the cell.
Passive-It is involved in the maintenance of the equilibrium level inside the cell.
Active transport is a dynamic process. Passive Transport is a physical process.
It is highly selective. It is partly non-selective
Active transport is a rapid process. Passive transport is a comparatively slow process.
Transpires in one direction. Transpires bidirectionally.
Active transportation is influenced by temperature. Passive transportation is not influenced by temperature.
In active transport, carrier proteins are required In passive transport, carrier proteins are not required
This process reduces or halts as the oxygen content level is reduced. This process is not affected by the level of oxygen content.
Metabolic inhibitors can influence and stop active transport. Passive transportation is not influenced by metabolic inhibitors.
Different types of Active Transport are –
Exocytosis, endocytosis, sodium-potassium pump Different types of Passive Transport are – Osmosis, diffusion, and facilitated diffusion
Complex sugar, ions, large cells, proteins and other particles are transported in this process. There are two types of Active transport:
Primary Active transport
Secondary Active transport
Exocytosis, endocytosis and sodium-potassium pump are a few examples of active transport. The process of endocytosis and exocytosis are utilized by all the cells for transportation of molecules which cannot passively permeate via the membrane.
Endocytosis is the process of active transportation of molecules into the cells by the action of engulfing it along with its membrane.
Exocytosis produces a counter function thereby forcing molecules out of the cell. The process of homeostasis facilitates an equal flow of molecules in and out of a cell which confers that the number of molecules that enter the cell through endocytosis equates to the number of molecules that exits a cell through the process of exocytosis. Both the processes assure that nutrients and wastes are balanced for the smooth functioning of the cells.
Explain primary active transport and secondary active
Primary active transport
In this process of transportation, the energy is utilized by the breakdown of the ATP – Adenosine triphosphate to transport molecules across the membrane against a concentration gradient. Therefore, all the groups of ATP powered pumps contain one or more binding sites for the ATP molecules, which are present on the cytosolic face of the membrane. Basically, the primary active transport uses external chemical energy such as the ATP.
Sodium-potassium pump, the most important pump in the animal cell is considered as an example of primary active transport. In this process of transportation, the sodium ions are moved to the outside of the cell and potassium ions are moved to the inside of the cell.
Secondary active transport
Secondary active transport is a kind of active transport that uses electrochemical energy. It takes place across a biological membrane where a transporter protein couples the movement of an electrochemical ion (typically Na+ or H+) down its electrochemical gradient to the upward movement of another molecule or an ion against a concentration or electrochemical gradient.
Electrochemical Gradient
Electrochemical gradient exists whenever there is a net difference in charges. The positive and negative charges of a cell are separated by a membrane, where the inside of the cell has extra negative charges than outside. The membrane potential of a cell is -40 to -80 millivolts.
The cell has higher potassium concentration inside the cell but lower sodium concentration than the extracellular fluid. The sodium ions will move inside the cell based on the concentration gradient and voltage across the membrane. The voltage across the membrane facilitates the movement of potassium into the cell, but its concentration gradient drives it out of the cell. The combination of voltage across the membrane and the concentration gradient that facilitates the movement of ions is called the electrochemical gradient.
the best examples of active transport include:
Phagocytosis of bacteria by Macrophages.
Movement of Ca2+ ions out of cardiac muscle cells.
Transportation of amino acids across the intestinal lining in the human gut.
Secretion of proteins like enzymes, peptide hormones, and antibodies from different cells.
Functioning of the White Blood Cells by protecting our body by attacking diseases causing microbes and other foreign invaders.
Proteins are negatively charged true or false
What’s re the types of transporters in active transport
An example of active transport is the sodium-potassium pump, which moves sodium ions to the outside of the cell and potassium ions to the inside of the cell.
True or false
True
The interior of living cells is electrically negative with respect to the extracellular fluid in which they are bathed. At the same time, cells have higher concentrations of potassium (K+) and lower concentrations of sodium (Na+) than does the extracellular fluid.
There are three types of these proteins or transporters: uniporters, symporters, and antiporters. A uniporter carries one specific ion or molecule. A symporter carries two different ions or molecules, both in the same direction. An antiporter also carries two different ions or molecules, but in different directions.
For example, your nerve cells (neurons) would not send messages to your brain unless you had protein pumps moving molecules by active transport.
The sodium-potassium pump (Figure below) is an example of an active transport pump. The sodium-potassium pump uses ATP to move three sodium (Na+) ions and two potassium (K+) ions to where they are already highly concentrated. Sodium ions move out of the cell, and potassium ions move into the cell. How do these ions then return to their original positions? As the ions now can flow down their concentration gradients, facilitated diffusion returns the ions to their original positions either inside or outside the cell.
True or false
When the cell concentrates potassium within, against the natural tendency of matter, it is performing active transport.
True or false
Plant cells also form tissues, such as the bark of a tree. And plant cells work together, forming organs, such as roots and leaves.
True or false
True for both
What are the three major fluid compartments in the internal environment (surroundings of the cell inside the body)
What is Homeostasis? ●Body cells work best if they have the correct ●Temperature ●Water levels ●Glucose concentration
●Your body has mechanisms to keep the cells in a constant environment.
True or false
What is homeostasis and state the homeostatic factors
There are three major fluid compartments; intravascular(plasma),interstitial, and intracellular
The ability of the body to maintain a relatively constant internal environment regardless of the changes that goes in the external environment.
Homeostatic factors ●Temperature ●Concentration of O2 and CO2 (metabolism). ●Blood Volume ●Blood pressure ●Concentrations of waste products ●Concentration of water, salt other electrolytes (Ca2+, Na+, etc.). ●Concentration of nutrients (energy). ● PH
How is homeostasis regulated
What is negative and positive feedback
The receptor:
●receives information that something in the environment is changing.
●The control center or integration center :
●receives and processes information from the receptor.
●The effector:
●responds to the commands of the control center by either opposing or enhancing the stimulus
Regulation of homeostasis
●Homeostasis is regulated by two feedback systems
Negative feedback
●A rise in the variable above a certain limit inhibits further production of that variable
●A fall below a certain limit withdraws the inhibition and permits the production.
Positive feedback
●An increase in a variable provokes further increase.
What is the constant body temperature of mammals
Why control temperature?
What is core body temperature
All mammals maintain a constant body temperature.
●Human beings have a body temperature of about 37ºC.
●E.g. If your body is in a hot environment your body temperature is 37ºC
●If your body is in a cold environment your body temperature is still 37ºC
Despite this, the body must be kept at a constant temperature of 37 °C. Why?
This is the optimum temperature for the body’s enzymes and other proteins. Even slight changes in body temperature can have a life-threatening effect on health.
If body temperature falls too low, reactions become too slow for cells to survive: too high, and the body’s enzymes are at risk of denaturing.
What is core body temperature?
The vital organs located deep within the body, such as the heart, liver and kidneys, are maintained at 37 °C. This is the core body temperature.
Skin temperature at the body’s extremities, such as the fingers and toes, is usually lower than the core body temperature.
On a warm day, skin temperature may be just 1 °C lower than the core body temperature, but on a very cold day it could be up to 9 °C lower.
