ksafa Flashcards
Characteristics of life
- Growth and Development
2.Maintain Homeostasis
- Reproduction
- Response to Environment or Stimuli
- Energy Processing
- Organized
It is any part of an organism’s environment that causes reaction
Stimulus
It is a common method of modification of the heat exchange for most mammals.
Piloerction
is the most common photosynthetic process and is seen in algae, cynobacteria and plants
Oxygenic photosynthesis
photosynthetic process that makes use of electron donors other than water
Anoxygenic Photosynthesis
enzymes that are retained intracellularly & function within the cell
Endoenzymes
enzymes transported extracellularly, where they break down large food molecules or harmful chemicals; cellulase, amylase, penicillinase
Exoenzymes
Control of enzyme synthesis
enzymes that are always present, always produced in equal amounts or at equal rates, regardless of amount of substrate; enzymes involved in glucose metabolism
Constitutive Enzymes
Control of enzyme synthesis
enzymes not constantly present, produced only when substrate is present, prevents cell from wasting resources
synthesis of these enzymes is induced by a metabolite
Induced Enzymes
Control of enzyme synthesis
Enzymes not produced when the end product of the pathway is present
synthesis of these enzymes is suppressed by a metabolite
Repressible Enzymes
Control of enzyme activity directly
Occurs when a substance that resembles normal substrate competes with substrate for active site
Competitive Inhibition
Control of enzyme activity directly
Characterized by a substance binding to the cofactor and distorts the shape of the active site
Noncompetitive Inhibition
Control of enzyme activity directly
Control mechanism wherein the concentration of product at the end of a pathway blocks the action of a key enzyme
Feedback Inhibition
Control of Enzyme Activity Categories
- Control of enzyme activity directly
- Control of enzyme activity by regulating enzyme synthesis
These are anabolic reactions to form covalent bonds between smaller substrate molecules, require ATP, release one molecule of water for each bond
Synthesis/condensation reactions
These are catabolic reactions that break down substrates into small molecules, requires the input of water
Hydrolysis Reactions
a type of chemical reaction that involves a transfer of electrons between two species.
Oxidation-Reduction Reaction
They convert one type of amino acid to another by transferring an amino group
Aminotransferases (or transaminases)
The transfer of phosphate groups, involved in energy transfer
Phosphorylation
Three types: Photophosphorylation, Substrate level phosphorylation, Oxidative phosphorylation
a model for enzyme-substrate interaction suggesting that the enzyme and the substrate possess specific complementary geometric shapes that fit exactly into one another.
Lock and Key Model
a model for enzyme–substrate interaction to describe that the substrate is capable of inducing the proper alignment of the active site of the enzyme, causing the latter to subsequently perform its catalytic function.
Induced Fit Model
Enzymes that contain protein (apoenzyme) and nonprotein (cofactors) molecules
Conjugated Enzymes or holoenzymes
Enzymes consisting of proteins alone
Simple enzymes
- biosynthesis
- building complex molecules from simple ones
- requires energy (ATP)
Anabolism
- degradation
- breaking down complex to simple molecules
- generates energy (ATP)
Catabolism
The sum total of all chemical reactions and physical workings occurring in a cell
Metabolism
- For a reaction to occur, an energy barrier must be surmounted
- the minimum quantity of energy which the reacting species must possess in order to undergo a specified reaction
Activation Energy
- Point when a reaction can easily run in either direction, to product or back to reactant
- Unstable at the highest energy level
- Substrate is bound most tightly to an enzyme in this state
Transition State
is where a small part of the chromosome is moved to another chromosome.
Translocation
is where a portion or part of the chromosome is lost during the cell division and the result is mostly lethal
Deletion
happens if the fragment joins the homologous chromosome, then that region is repeated
Duplication
- some call this as chromosomal rearrangements.
- In this disorder, there is a part of chromosome that is affected
Chromosomal Alterations
- has 45 chromosomes because there is no Y chromosome
- They are genetically female, but they do not mature sexually during puberty
Monosomy X (Turner’s Syndrome)
- has 47 chromosomes and this time there are three X chromosome and no Y chromosome
- female
- Their distinct features include widely spaced eyes, abnormally curved pinky fingers, flat feet and abnormally shaped breastbone
Trisomy X (Triple X Syndrome)
- has 47 chromosomes, just like Klinefelter, but this is because there is a pair of Y chromosome instead of just 1
- Person with this abnormality has no distinct physical features and mostly show behavioral difference
XYY Syndrome
- has 47 chromosomes because there is a pair of X chromosome instead of just 1
Klinefelter’s Syndrome
- occurs when pairs of homologous chromosomes or the sister chromatids fail to separate during anaphase I or anaphase II (rare in mitosis)
Nondisjunction
- From the name itself, it implies that there is an excess chromosome in chromosome 21.
- down syndrome
Trisomy 21
- this means that there is an excessive copy of chromosome (normally it is a pair (2) but in these cases, there are 3 chromosomes)
Excessive Chromosomes (Autosomes)
it is the abnormality in the number of chromosomes; either there is too much or too few
Aneuploidy
- it is the production of female gametes (ova) within ovaries (sometimes it happens in the oviduct)
- starts during fetal development
Oogenesis
is the haplid cell which is formed by meiosis in spermatocytes
Spermatid
Differentiation of spermatids to spermatozoa
Spermiogenesis
- complete process of meiosis I and meiosis II to produce 4 spermatids
Spermatocytogenesis
CAUSES OF VARIATIONS
- Crossing Over in Prophase I
- Independent Assortment in Metaphase I & II
- Random Fertilization
differences between members of population
Variation
- produces body/somatic cells
- produces diploid cells
- daughter cells are genetically identical
- cell division and replication occurs ONCE
Mitosis
Mitosis
- chromosomes condense
- microtubules form
- nuclear envelope breaks down
Prophase
Mitosis
- chromosomes are pulled to the center of the cell
- Line up along “metaphase plate”
Metaphase
Mitosis
- centromeres divide
- spindle fibers pull one set of chromosomes to each pole
- Precise alignment is critical to division
Anaphase
- Nuclear enveope form around the chromosomes
- chromosomes uncoil
Telophase
- Found majority on eukaryotic cells and considered as the largest organelle, accounting for around 10% of the cell’s volume
Nucleus
- is the process of selectively permeable nuclear envelope separates the contents of the nucleus from that of the cytoplasm
Cell Compartmentalization
- Major site of synthesis in the cell
- This is a flattened sac network (cisternae) that is continuous with the outer nuclear membrane
Endoplasmic Reticulum
- takes proteins from the cytosol and continues its production in the golgi apparatus until completion
Rough Endoplasmic Reticulum
is important in lipid, phospholipid and steroid synthesis
Smooth Endoplasmic Reticulum
- Mostly present in eukaryotic cells which is responsible for packaging of macromolecules into vesicles so that is can be sent out to their site of action
Golgi Apparatus
- It has inner and outer membrane with an intermembrane space in between
- The outer membrane contains proteins known as porins that enable ion movement to and from mitochondrion
- The inner membrane includes a number of enzymes such as ATP synthase that produces ATP in the matrix and carries proteins that control metabolite movement into and out of the matrix
Mitochondria
- An acidic membrane-bound organelle that contain numerous hydrolytic enzymes which catalyze hydrolysis reactions
Lysosomes
- Consists of single membrane and granular matrix scattered in the cytoplasm
- Contain enzymes involved in a variety of metabolic reactions including several aspects of energy metabolism.
Peroxisomes
- Surrounded by a membrane called tonoplast which encloses fluid containing inorganic materials like water and organic materials like nutrients and enzymes
Vacuoles
A membrane-bound organelle containing liquid or cytosol which is enclosed by a lipid bilayer.
Vesicles
It is a type of plastid that involved in photosynthesis in plants and algae.
Chloroplast
Non-membrane
- It is a structure of cells which produces protein
- Many cellular functions such as repairing damage or directing chemical processes require protein
Ribosomes
Non-membrane
- It is an organelle that helps cell divide or make copies of themselves
- Each cell has a pair of these in the centrosome, a region near the nucleus
Centrioles
Non-membrane
- It is a network of microscopic molecular filaments found in the cytoplasm of all nucleated eukaryotic cells
Cytoskeleton
Cell Modifications
- Also called brush/striated border
- They are finger-like cytoplasmic extensions of the apical surface which increase surface area for absorption
Microvilli
Cell Modifications
Appears as short hair-like structures or projections
Cilia
Cell Modifications
- They have the same axial structure with cilia but much longer that also functions with movement
Flagella
Cell Modifications
- They support the epithelium and also functions as a passive molecular sieve or ultrafilter
Basal Infoldings
Cell Modifications
- They are intercellular adhesion complexes in epithelia and endothelia that control paracellular permeability
Tight Junctions
Cell Modifications
- This is an element of the cell-cell junction in which cadherin receptors bridge the neighboring plasma membranes via their hemophilic reactions
Adherens Junction
- is one of the essential structures common to all cell types
- It acts as a barrier that separates the cytoplasm from the cell’s outer surroundings
Cell or Plasma Membrane
- a two-layer of phospholipid oriented in opposite direction
- A phospholipid molecule consists of a glycerol molecule bonded to a phosphate “head” group and two fatty-acid “tails”.
Phospholipid Bilayer
Phosphate head:
- means attracted to water molecules
Hydrophilic
Phosphate tail:
- means water-dreading or it repels water
Hydrophobic
Since phospholipid molecule is comprised of two different ends, it is called?
amphiphilic or amphiphatic
- can freely move within the lipid bilayer because of its fluidity
- they may also be confined to certain areas of the bilayer
Membrane Proteins
- also known as intrinsic proteins are embedded entirely in the lipid bilayer
- They are usually alpha-helices forming transmembrane region
- extending through the lipid bilayer such that one end reaches the interior of the cell and the other extends in the outside
Integral Proteins
- are attached to either inner or outer layer of the phospholipid bilayer
- They are easily separable from the lipid bilayer, that can be removed in any way without harming the bilayer
Peripheral Proteins
- are a very narrow tube-shaped protein that help establish a tiny pore in the cell membrane
- They are only large enough to allow an ion to go through
Ion Channels
They are embedded in the cell membrane to help transport too large molecules such as glucose and amino acids to go through ion channels across the membrane
Transporter or Carrier Proteins
are chemicals that catalyze and causes chemical reactions to occur
Enzymes
also known as cell identity markers
Recognition Sites
- They are located in between few phospholipid molecules
- It helps the cell membrane maintain the appropriate level of fluidity by managing the space between phospholipids
Cholesterol
- Model used to describe the cell membrane
- This is because the structure of the membrane is flexible and fluid rather than a rigid solid barrier
The Fluid Mosaic Model
- is a naturally-occurring phenomenon and does not require the cell to exert any of its energy to accomplish the movement
Passive Transport
- All forms of passive transport involve
- substances simply move from an area of higher concentration to an area of lower concentration
Diffusion
Factors that affect the rate of diffusion:
- The greater the difference in concentration, the faster the molecules will go down the concentration gradient, hence more rapid diffusion
Concentration Gradient
Factors that affect the rate of diffusion
- Higher temperatures increase the energy and therefore the movement of the molecules, increasing the rate of diffusion
- Lower temperatures decrease the energy of the molecules, thus decreasing the rate of diffusion
Temperature
Factors that affect the rate of diffusion
- Heavier molecules move more slowly; therefore, they diffuse more slowly. The reverse is true for lighter molecules
Mass of Particles
Factors that affect the rate of diffusion
- Diffusion is significantly influenced by viscosity and density
- The denser or viscous the medium is, the harder it is for the given particle to diffuse through it.
Solvent Properties
- is a form of passive transport in which substance moves down its concentration gradient without the use of transport proteins
Simple Diffusion
- a form of passive transport wherein materials diffuse across the plasma membrane with the help of membrane proteins.
Facilitated Diffusion
a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one, thus equalizing the concentrations on each side of the membrane.
Osmosis
- the pressure that must be applied to the solution side to stop fluid movement when a semipermeable membrane separates a solution from pure water
Osmotic Pressure
- any external solution that has the same solute concentration and water concentration compared to body fluids
Isotonic Solution
- refers to the relative concentration of solutes in the water inside and outside the cell
Tonicity
- the solute concentration is higher outside the red blood cells than inside, Because the concentration of water molecules inside the cell is higher than outside, water moves out of the cell, causing the cell to shrink and shrivel
Hypertonic Solution
- the solute concentration is lower outside the red blood cell than inside
Hypotonic Solution
- The plant cell is said to have become swollen and hard
Turgid
- is the resulting force of water against the cell wall
Turgor Pressure
- If the plant cell is then observed under a microscope, it will be noticed that the cytoplasm has shrunk and pulled away from the cell wall. This phenomenon is called?
- Due to loss of water of cell
Plasmolysis
- This can be reversed as soon as the cells are transferred into a hypotonic solution in the process
- opposite process of plasmolysis
Deplasmolysis
- a cell uses transport protein to move a substance against its concentration gradient—from an area of lower concentration to an area of higher concentration
Active Transport
Transport protein that transports a single type of molecule or ion
Uniporter
Transport protein that transports two molecules or ions in the same direction
Symporters
Transport protein that transports two molecules or ions in the opposite direction
Antiporter
- a difference in the electrical potential (voltage) across their cell membrane.
Membrane Potential
- a small sac that can pinch off or fuse with a cell membrane.
Transport Vesicle
- Endocytosis and exocytosis together provide _____________ , because many molecules are moved at the same time
Bulk Transport
- cell membrane engulfs fluids or large molecules to bring them into the cell
Endocytosis
- “cell eating” is the process by which large particles, such as cells or relatively large particles, are taken in by a cell
Phagocytosis
- “cell drinking” and was named at a time when the assumption was that the cell was purposefully taking in extracellular fluid
Pinocytosis
is a form of endocytosis in which receptor proteins on the cell surface are used to capture a specific target molecule.
Receptor-mediated Endocytosis
is a form of bulk transport in which materials are transported from the inside to the outside of the cell in membrane- bound vesicles that fuse with the plasma membrane
Exocytosis
Process in which a parent cell divides, giving rise to two or more cells
Cell Division
process by which a nucleus divides, resulting in the segregation of the genome to opposite poles of a dividing cell
Nuclear Division
a thin fibrous form of DNA and proteins
Chromatin
identical structures that result from chromosome replicaition, formed during S phase
Sister Chromatid
condensed DNA (from DNA Helix)
Chromosome
sequence of phases in the life cycle of a cell
Cell Cycle
is the longest event in the cell cycle, specifically in the S phase where the DNA must be copied
Interphase
“inter” means
In between
- cell is recovering from mitosis
- growth
G1 Phase
- DNA replicates
- growth and DNA synthesis
S Phase
- preparation for mitosis
- organelles are replicated
G2 Phase
phase in which they are inactive in the sense that the cells are not dividing or preparing to divide
G0 Phase
- cell’s control system
- cell cycle stops until a go-ahead signal is received
Checkpoints
Checkpoint
- Restriction point
- enough nutrients
- enough organelles
- growth that happens
G1 Checkpoint
Checkpoint
Enough genetic material
G2 Checkpoint
Checkpoint
line-up of chromosomes in the equatorial region
M Checkpoint
- if the cell does not receive the go-ahead sugnal, it will exit the cycle, switching into a non dividing state called?
G0 Phase
the proteins that interact to regulate the cell cycle are called (?) because they undergo a constant cycle of synthesis and degradation during cell division
Cyclins
the proteins that interact to regulate the cell cycle are kinases which either activates or deactivates another protein through phosphorylating them.
Cyclin-dependent Kinase
is a cyclin-cdk complex that triggers a cell’s passage past the G2 checkpoint into the M phase
Maturation-promotion Factor
These are cells that are like clay that is ready to be molded to get a specific shape
Stem cells
are cells that don’t stop dividing and growing even if there is already enough of them in an area
Cancer Cells
- implies, it is a progressive damage in nerve cells
- We can say that it is the loss of nerve structure and function which are notable in the diseases such as Alzheimer’s, Huntington’s and Parkinson’s.
Neurodegeneration
is the most widespread and known degenerative disease and is characterized by memory loss
Alzheimer’s
it is an inherited disorder characterized by neuronal dysfunction and degeneration in striatum and cerebral cortex
Huntington’s
is also about cell deaths but targeting those neurons responsible for movements
Parkinson’s
- biotechnology is the process of creating copies of DNA fragments, cells or organisms
Cloning
as fragments of tissue from an animal or plant are transferred to an artificial environment in which they can continue to survive and function
Tissue Culture
- a division of nucleus that reduces the chromosome number by half
- REDUCTION DIVISION
- Daughter cells produces are not genetically identical to one another
- cell division takes place TWICE, but replicates ONCE
Meiosis
each chromosome in pair are identical to other (carry genes for same trait
Homologous Pair
pairing of homologous chromosomes forming a tetrad
Synapsis
chromatids of tetrad exchange parts
Crossing over
Meiosis
- chromosomes condense
- homologous chromosomes pair with each other
- each pair contains four sister chromatids
- tetrad
Prophase I
Meiosis
- spindle fibers attach to the chromosomes through their centromeres
- while this is happening the chromosome continue to condense
Prometaphase
Meiosis
- Tetrads or homologous chromosomes move to the center of the cell
- independent assortment occurs
- 2 homologous chromosomes will separate
Metaphase I
Meiosis
homologous chromosomes pulled to opposite poles
Anaphase I
Meiosis
Daughter nuclei formed
haploid
Telophase I
Meiosis
- daughter cells undergo a second division much like mitosis
- no additional replication occurs
Meiosis II
Meiosis
Spindle fibers form again
Prophase II
Meiosis
Sister chromatids move to the center
Metaphase II
Meiosis
- centromeres split
- sister chromatids are pulles to poles
Anaphase II
Meiosis
- Four non-identical haploid daughter cells result from one original diploid cells
Telophase II
- Tissue that performs different functions depending on the type and position of the cells in the plant, including:
> parenchyma (photosynthesis in the leaves and storage in the roots)
> collenchyma (shooting support in areas of active growth)
> schlerenchyma (shooting support in areas where growth has stopped)
Ground Tissue
- It is involved in the collection and transmitting of information through detecting stimuli- external and internal signals
- It is composed of two main cell types: neurons or nerve cells and glia
Nervous Tissues
Tissue that covers and protects the plant and monitors exchange of gases and absorption of water in roots
Dermal Tissue
Tissue that transports water, minerals and sugars into different parts of the plant
Vascular Tissue
Main Postulates of Cell Theory
- All known living things are made up of cells.
- The cell is a structural and functional unit of all living things.
- All cells come from pre-existing cells by division.
Additional Postulates for Cell Theory
- All cells contain hereditary information which is passed from cell to cell
during division.
- All cells are basically the same in chemical composition.
- All energy flow of life occurs within cells.
- are large, complex molecules playing several critical roles in the body
- It does most of the work in cells and are necessary for the tissues and organs of the body’s structure, function and control
Proteins
- performs a range of function such as providing energy, structural support and cellular communication
- It has the most important function as a source of energy.
Carbohydrates
- are the basic building blocks for all cells and they play many important and varied roles
- they are made up of fatty acids that can either be saturated or unsaturated
- They are important components of the plasma membrane and other cellular compartments
Lipids
have two types: deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
Nucleic Acids
- unicellular
- found in bacteria
- reproduce through binary fission
- circular DNA structure
- rigid cell wall from glycoproteins (Murein)
- asexual reproduction
- Lack membrane-bound organelles
- Lack membrane-bound nucleus
- Nucleoid: cytoplasm area where majority of their DNA is in a chromosome-like
Prokaryotic Cells
- multicellular
- found in plants, animals, fungi, protists
- reproduce through mitosis
- linear DNA structure
- sexual reproduction
- Contains organelles enclosed in membranes (Golgi Body and endoplasmic reticulum)
- store their DNA as chromosomes within the nucleus
Eukaryotic Cells
Similarities of Prokaryotic and Eukaryotic
- Both have ribosomes -Both have DNA responsible for genetic coding
- Both have plasma membrane
- Both have cytoplasm - Both have plasma membrane
Tissue that consists of closely packed sheets of cells covering
surfaces- including the outside of the body- and cavities of the body wall
Epithelial Tissue
- Tissue made up of cells that are suspended in an extracellular matrix
- supports and, as the name implies, binds other tissues
- The most abundant and widely distributed tissues that also functions as protection
Connective Tissue
- cells, often referred to as muscle fibers contain actin and myosin proteins which allow them to contract
- Important tissue in holding the body stable, enabling it to move and also pumping blood and pushing food through the digestive tract
Muscle Tissue
- also striated-striped- muscle is what we refer to in daily life as muscle
- is attached by tendons to the bones, which helps you to regulate your movements consciously
Skeletal Muscle
- muscle is found in blood vessel walls, digestive tract walls, uterus, urinary bladder and various other internal structures
- is not striated and its involuntary, not under conscious control
Smooth Muscle
muscle that can only be seen in the walls of the heart
Cardiac Muscle
- “Father of Modern Pathology”
- He published his now famous aphorism “omnis cellula e cellula” which means “every cell stems from another cell.”
Rudolf Virchow
- Zoologist
- also studied different animals using his microscope and later on concluded that animals are made up of cells
Theodor Schwann
- line the cavities and surfaces of the body such as the inside of the stomach and the outermost skin layer
Epithelial Tissues
- Tissues that supports, protects and binds certain parts of the body such as muscles
Connective Tissue
- can receive stimuli and conduct electrical impulses.
Nervous Tissue
Muscles of the body that produce movement by contraction and expansion
Muscular Tissue
Plants have outer coverings formed by ?
Dermal Tissue
- a Dutch spectacle-maker who discovered the first compound microscope which was later disputed as many had invented their own versions of glass lenses across Europe to be used at that time
Zachrias Janssen
- he is known for telescope
- he was alsoable to make his own microscope because of his knowledge about glass and focal lengths
- It has two new lenses same as his telescope: a bi-convex objective and a bi-concave eyepiece
Galileo Galilei
- “Father of Microbiology”
- he made his own very odd looking version. But, with his strange looking microscope, he was able to discover bacteria and protozoa
- used his dental scraping to look for bacteria and protozoa
Antony van Leeuwenhoek
- Antony van Leeuwenhoek did not call them bacteria but instead he called it?
Animalcules
- he was able to coin the term “cell” by looking at a piece of cork stripped from the trunk of the Cork Oak tree under his microscope.
Robert Hooke
- a German botanist who loves observing his plants under the microscope, noticed that every plant is made up of cells
Matthias Schlieden
