CELLS Flashcards
Functional and structural unit of all living organisms
Cell
Discovered in the middle of the 17th century after the microscope was invented
Cell
What is Cell theory?
- All living things are composed of cells.
- Cells are the basic units of structure and function for living things.
- All cells come from pre-existing cells. Also, organisms grow by “adding on more cells” NOT by increasing the size of their cells.
Contributor to the Cell theory?
Robert Hooke Antonie Van Leeuwenhoek Matthias Jakob Schleiden Theodor Schwann Rudolf Virchow
In 1655, He was the first to identify cells and he name them
Hooke
In 1674, because he made better lenses, he was the first to look at cells in much clearer and greater detail
Leeuwenhoek
In 1838, he was the first to note that plants are made of cells
Schleiden
in 1839, he concluded that all living things are made of cells
Schwann
in 1855, he proposed that all cells come form other cells
Virchow
In what year did the biologist discovered that organisms are made out of cells?
1830s
- has nucleus
* has membrane-bound organelles
Eukaryotic
Cells
- lack nucleus and membrane-bound organelles
* has nucleoid
Prokaryotic Cells
3 major components of all cells
Plasma membrane
Cytoplasm
Genetic material
Plasma Membrane
outer boundary of the cell that separates internal events from the environment
- protective covering of the cell
Cytoplasm
has semifluid cytosol and small structures called organelles (“little organs”)
Genetic material
-DNA
- Can be found inside the nucleus
_ in a bacteria, the genetic material is not found in the nucleus—-stored in a membrane bound nucleus (Nucleoid)
Cell shapes and Sizes: Cocci
Round thingy
Cell shapes and Sizes: Bacilli
Rod shaped
Cell shapes and Sizes: Spirilli
Spiral
Cell shapes and Sizes: vibrios
comma
Cell shapes and Sizes:Filamento
like a twig
Bacterial Cell Arrangement: Diplococci
2 round thingy, a pair of round thingy
Bacterial Cell Arrangement: Streptococci
round thingy arrange in a snaky pattern chuchu train
Bacterial Cell Arrangement: Staphylococci
round thingy grape like structure
a semipermeable membrane
a phospholipid bilayer with interspersed proteins and other molecules
Cell Membrane
phospholipids
major components of cell membrane
components of the phospholipids
each consists of two hydrophobic “tails” (water dreading)
and a hydrophilic phosphate “head” (water attracting)
contain cholesterol that make membrane less permeable or modulates membrane fluidity
Cell Membrane
Cell Membrane: Proteins
- Receptor protein
- Channel protein (always open)
- Gated Channel protein (always closed)
- Transport Protein
- Glycoprotein
the basic unit of life
Cell
arise from pre-existing cells
Cell
What is a Plasma/ Cell Membrane
the membrane found in all cells that separates the interior of the cell from the outside environment. In bacterial and plant cells, a cell wall is attached to the plasma membrane on its outside surface.
Plasma/Cell Membrane Characteristics
a semipermeable membrane
a phospholipid bilayer with interspersed proteins and other molecules
Phospholipid Bilayer
a thin polar membrane made of two layers of lipid molecules
Phospholipid Bilayer Parts: Hydrophobic Tail
water-fearing,” part of a phospholipid consists of its long, nonpolar fatty acid tails. The fatty acid tails can easily interact with other nonpolar molecules, but they interact poorly with water.
- prevent phospholipid molecules from packing together and forming a solid.
- repelled by water molecules attracts each other instead
Phospholipid Bilayer Parts: Hydrophilic Head
- Water loving
- attracted to water molecules
Plasma/ cell Membrane Parts: Glycoprotein
proteins with carbohydrates attached
Plasma/ cell Membrane Parts: Glycolipid
lipid with carbohydrates attached
Major component of the cell membrane
Phospholipids
Composed of two hydrophobic tails (water- dreading) and a hydrophilic phosphate “head”(water- attracting)
Phospholipids
contains cholesterol that makes the ,membrane less permeable or modulates membrane fluidity
Cell Membrane
PROTEINS ON THE CELL MEMBRANE
Receptor protein Channel Protein Gated Channel Protein Transport Protein Glycoprotein
PROTEINS ON THE CELL MEMBRANE: Receptor Protein
Transmit signals or informations into the cell
PROTEINS ON THE CELL MEMBRANE: Channel Protein
- A type of transport protein
- They have the ability to form hydrophilic pores in cell membrane transporting molecules down the concentration gradient.
- always open
PROTEINS ON THE CELL MEMBRANE: Gated Channel protein
-transport protein that opens a gate allowing an a molecule to pass through the membrane.
PROTEINS ON THE CELL MEMBRANE: Transport Protein
protein that serves the function of moving other materials in an organism
Cell Membrane Parts
Phospholipid bilayer Cholesterol Proteins Cytoskeleton Filaments carbohydrates groups
appear as a large rounded oval structure that contains the DNA and is the control center of the cell
NUCLEUS
DNA
Deoxyribonucleic Acid
- Hereditary Material in humans
- the blueprint of life
- exists in combination with protein (histones) in the form of chromatin
- chromatin condensed into chromosomes (cell division)
is the location where DNA is transcribed into RNA. Then the RNA is translated at ribosomes into proteins that determine a cell’s activities
Nucleus
nucleoplasm
Inside the nuclear membrane is the nucleoplasm, which main function is to store DNA and facilitate an isolated environment where controlled transcription and gene regulation is enabled. The nucleoplasm contains several non-membrane bound substructures,such as nuclear bodies and nuclear speckles.
nuclear envelope
is a membrane that separates the nucleus from the cytoplasm; continuous with the ER
nuclear pores
penetrate the surface of the nuclear envelope that allow materials to enter and the leave the nucleus; the pores prevents DNA from leaving the nucleus but permits the RNA to be moved out
nucleolus
is the preassemble point for ribosomes
Chromosome
- Two chromatids
- Centromere
When mitosis is about to begin, the chromatin packs even more tightly, giving rise to visible chromosome
RIBOSOME
- protein work benches
- sites for protein synthesis
Types of ribosome
Attached Ribosomes in the Endoplasmic reticulum
- Free Ribosomes ( Scattered in the Cytoplasm
Usually cluster in groups connected by the messenger RNA (MMRNA) called the polysomes
Ribosomes
a flattened sheets, sacs, and tubules scattered throughout the cytoplasm and continuous to the nuclear envelope
Endoplasmic Reticulum
what is the function of the endoplasmic reticulum
Production (e.g. lipids) and Transportation of molecules (e.g. proteins) —– POSTAL service of the cell
Types of ER: RER
Rough Endoplasmic Reticulum
with ribosomes
to make proteins
Types of ER: SER
- Smooth Endoplasmic Reticulum
- Without ribosomes
- synthesizes lipids, phospholipids as in plasma membranes and steroids.
Golgi apparatus/complex
composed of flattened stacks of 3 – 12 cisternae
It is an organelle responsible in sorting , packaging, and secretes proteins and lipids
Golgi Apparatus/complex
Who discovered the golgi apparatus?
Camillo Golgi
when was the golgi apparatus discovered?
1898
Golgi Apparatus: Cis Face
“Receiving”side
Golgi Apparatus: Trans Face
“shipping side”
GOLGI APPARATUS PARTS
Cis face Trans Face Cisternae Transport Vesicle from the Golgi Transport vesicle from the RER Secretory vesicle from trans face.
a series of flattened, curved membrane saccules of the ER and Golgi Apparatus
Cisternae
spherical organelles that contain acid hydrolase enzymes that break down material brought into the cell, waste organic molecules, and worn organelles
lysosomes
PARTS OF THE LYSOSOME
MEMBRANE
DIGESTIVE ENZYMES AND ACID
PARTIALLY DIGESTED ORGANELLE
It act as a floating garbage disposals for cells, digesting and recycling cellular waste products and consumed material.
LYSOSOMe
“garbage collector” of the cell
lysosome
Sequester diverse oxidative reactions and play an important roles in metabolism, reactive oxygen species detoxification, and signaling
Peroxisomes
are vesicle-like structures
contain enzymes that break down hydrogen peroxide (H2O2) molecule to water and oxygen
or H2O2 induce DNA damage and cause cell death
Peroxisomes
used for temporary storage and transport
Vacuoles
occur in several shapes and various functions. In animal cells they help sequester waste products. In Plant cells , they help maintain water balance
Vacuoles
only few animals have this
vacuole, Fat cells contain a very large lipid, engorged vacuole.
Power generators, Powerhouse of the cell
mitochondria
They generate the most chemical energy needed to power the cell’s biochemical reactions.
Mitochondria (plural)
Mitochondrion ( Singular)
produce adenosine triphosphate (ATP) —- basic chemical fuel that powers the cell’s activities through cellular respiration
Mitochondria
ATP
Adenosine Triphosphate—basic chemical fuel that powers the cell’s activities through cellular respiration.
Stage 1: Glycolysis
linear metabolic pathway of enzyme-catalyzed reactions that convert glucose into two molecules of pyruvate (Pyruvic Acid) in the presence of oxygen or into two molecules of lactate in the absence of oxygen.
Stage 2: Krebs cycle
a sequence of reactions in the living organism in which oxidation of acetic acid or acetyl equivalent provides energy for storage in phosphate bonds (as in ATP) called also citric acid, tricarboxylic acid cycle.
aste product; carbon dioxide
Finish product; oxaloacetic acid
STAGE 3: ELECTRON TRANSPORT CHAIN/ ATP SYNTHASE ACTION
a series of electron transporters embedded in the inner mitochondrial membrane that shuttles electrons from NADH and FADH2 To molecular oxygen. In the process protons are pumped from the mitochondrial matrix to intermembrane space, and oxygen is reduced to form water.
MITOCHONDRIA PARTS
- MATRIX
- OUTER MEMBRANE
- SPACE BETWEEN MEMBRANES
- FOLDS
- INNER MEBRANE
network of interconnected filaments and tubules that give shape and texture to a cell
Cytoskeleton
can be compared to the bones and muscles of an animal
cytoskeleton
Cytoskeleton: Microfilaments
-strands made of spherical protein subunits called actins
Cytoskeleton: Intermediate Filaments
tough protein fibers constructed like woven ropes composed of tetrameter () fibrils
Cytoskeleton: Microtubules
hollow tubes of spherical protein subunits called tubulins
play an essential role in cell division
Centrioles
participates in the formation of the spindle fibers which assists the movement of chromosomes
Centrioles
in charged of movement of the cells
Cilia and Flagella
elongated appendages on the surface of some cells that are used for movement
Cilia and Flagella
5 – 20x longer than cilia
Flagella
numerous and shorter
, and is used for movement
Cilia
the movement of particles (solute) across or through a membranous barrier
Membrane Transport
Different types of membrane transport
- Simple diffusion
- Facilitated diffusion
- primary active transport
the movement of molecules through a cell membrane without using the channels formed by integral membrane protein.
Simple diffusion
the transport of substances across a biological membrane from an area of higher concentration to an area of lower concentration with the help of a transport molecule.
Facilitated diffusion
also called direct active transport, directly uses chemical energy (such as from adenosine triphosphate or ATP in case of cell membrane) to transport all species of solutes across a membrane against their concentration gradient.
primary active transport
Size and charge affect the rate of diffusion across membrane
TRUE
Hydrophobic molecules
O2, CO2, N2
Small uncharged polar molecules
H20, INDOLE, GLYCEROL
Large uncharged polar molecules
Glucose, sucrose
ions
CI-, k+ Na+
refers to the relative concentration of solutes in the water inside and outside the cell
tonicity
membranes are permeable to ions, less to water
False, membranes are permeable to WATER, less to IONS
a solution that does not cause an osmotic flow of water into or out of a cell is called?
ISOTONIC (iso- same+ tonos- tension)
causes osmotic water flow into the cell. If red blood cells is placed in this solution it will swell up like a balloon and may eventually burst releasing ist contents.
HYPOTONIC
HEMOLYSIS
the process in which a a red blood cell swell like a balloon and then burst.
- hemo (blood)
- lysis- loosening
exposure to this solution results in the osmotic movement of water OUT of the cell
HYPERTONIC
HYPERTONIC SOLUTION: As water moves out, the cell shrivels and dehydrates. The shrinking of red blood cells is called what?
Crenation, and the cells are said to be crenated
mechanism by which large molecules get into and out of the cells
Endocytosis and Exocytosis
TYPES OF ENDOCYTOSIS
PHAGOCYTOSIS
PINOCYTOSIS
cellular eating- solid
PHAGOCYTOSIS
cellular drinking- fluids
PINOCYTOSIS
ligands bind to specific receptors on cell surface
Receptor mediated Endocytosis