chapter 3 Flashcards
outer part of the cell which separates the cell’s internal environment from its external environment
plasma membrane
inside of the cell which contains the intracellular fluid and all the organelles embedded in it
cytoplasm
most prominent part of the cell, houses the DNA and is the control center of the cell
Nucleus
another term for the plasma membrane
phospholipid bilayer
plasma membrane consists of three things
phospholipids
cholesterol
proteins
why do we use the fluid mosaic model to describe the plasma membrane
because it is not a ridged structure, it’s very fluid - the proteins move around in the membrane.
why is the plasma membrane called a bi-layer
it has two layers the outside is Phospho which is hydrophilic meaning it loves water and lipid layer on the inside is hydrophobic meaning it is scared of water.
what are the three main components of the cell
plasma membrane - (outer) separates internal from external
cytoplasm- contains cytosol the intracellular fluid and all the organelles embedded in it
nucleus - which houses the DNA and is the control center of the cell
describe the two body fluid types in the body
intracellular fluid - found inside the cell called cytosol
extracellular fluid - found outside the cell and includes:
cerebrospinal fluid
plasma
and lymph - found in lymphatic vessels
what are the proteins of the plasma membrane
integral proteins
peripheral proteins
glycoproteins
these proteins extend into the plasma membrane
Integral proteins
these proteins are found on the surface of the plasma membrane
peripheral proteins
these proteins have one or move carbohydrates attached
Glycoproteins
what are the functions of the plasma membrane
to provide a boundary between internal and external environment.
It is selectively permeable - so the membrane selects what can and cannot pass through the membrane.
it has cell recognition
and it can communicate through receptors that receive communication and cell binding which binds tissues together
what are the three ways to move things through the plasma membrane
passive transport
active transport
vesicular transport
what are the three types of passive transport
simple diffusion
facilitated diffusion
osmosis
this type of transport requires no energy but does require a concentration gradient.
simple diffusion
movement from an area of high concentration to an area of low concentration
simple diffusion
list three examples of things that move through simple diffusion
oxygen
carbon dioxide CO2
urea
this type of transport is highly selective and uses channel or carrier proteins
facilitated diffusion
diffusion that needs help from a transport protein; is used to regulate flow of ions and glucose
facilitated diffusion
give two examples of things that move through facilitated diffusion
ions
glucose
This type of transport uses energy to pump substances across the membrane against its concentration gradient
active transport
what is a type of active transport
sodium potassium pump maintains ion balance of sodium (NA+) and potassium (k+) in the cell
movement of substances from out of the cell into the cell via vesicles
endocytosis
movement of substances from inside the cell out of the cell via vesicles
exocytosis
water moving from an area of high solutes to an area of low solutes
osmosis
only refers to a net diffusion of water across a semi-permeable membrane
osmosis
give an example of osmosis
the movement of water from the intracellular fluid to the extracellular fluid and vice versa
specialized cells that engulf and destroy bacteria
phagocytes
“cell eating” large solid particles such as bacteria or viruses or aged or dead cells are taken in by the cell
phagocytosis
“cell drinking” cells take up the droplets of extracellular fluid. occurs in most body cells and takes in any and all solutes dissolved in the extracellular fluid
pinocytosis
is vesicular transport active or passive
it requires energy so it is active
a solution with a high concentration of water and a low concentration of solutes,
hypotonic
the fate of a cell placed in a hypotonic solution
it will swell or expand and could possibly burst in blood cells this is called hemolysis
a solution with the same concentration of water and solutes
isotonic
what happens to a cell placed in a isotonic solution
it stays the same
a solution with a low concentration of water and a high concentration of solutes,
hypertonic
what happens to a cell placed in a hypertonic solution
shrinks or crenates
Small and non-polar molecules like oxygen co2 and urea use this type of transport
simple diffusion
Large, polar or charged molecules that need the help of a transport protein such as a channel protein or a carrier protein use this type of transport
facilitated diffusion
what is the difference between a channel protein and a carrier protein?
a channel protein make a channel that the molecule can move through and a carrier protein is like a revolving door it loads up with molecules on one side and moves through and then discards the molecules on the other side.
the most important transport protein in the body is
the sodium potassium pump because it maintains the ion balance of the sodium and potassium
the fluid inside of the cell that is 75-90% water and the remainder is organelles, nutrients, ions, gasses, wastes and inclusions.
Cytosol
The site of chemical reactions in the cell
Cytosol
What are the three components of the cytoskeleton
microfilaments, intermediate filaments and microtubules
concentrated at the periphery of the cell and contribute to the cells strength and shape. providing mechanical support and helping generate movement and also provide support for microvilli.
microfilaments
microscopic fingerlike projections supported by the microfilament, involved in muscle contraction, cell division and cell locomotion.
microvilli
thicker than microfilaments but thinner than microtubules, found in parts of cells subject to tension, they help hold organelles such as the nucleus in place and help attach cells to one another
intermediate filaments
the largest of the cytoskeletal components are long hollow tubes that help determine cell shape and function in both movement of organelles, such as secretory vesicles, within a cell and the migration of chromosomes during cell division. They are also responsible for movements of cilia and flagella.
microtubules
the rod like structures near the nucleus that create the mitotic spindle on the centromere during cell division
centrosomes
numerous short hair-like structures that move in a brushing motion
cilia
where is the cilia located
airways and uterine
long tail like structures that have a whip-like movement for locomotion
flagella
what is the only example of flagella in the human body
sperm
the organelle that is the site of ATP synthesis
mitochondria
the organelle that destroys old organelles / pathogens with acids or digestive enzymes
lysosome
the organelle that sorts, modifies, and packages proteins
Golgi aparatus
the organelle that is made of RNA and assembles or manufactures amino acids into proteins
ribosome
the organelle that is the site of lipid synthesis and detoxification
smooth endoplasmic reticulum
the organelle that produces the mitotic spindle during mitosis
centrosome
the organelle that degrades fatty acids and toxic foreign material
peroxisome
the organelle that is the site of protein synthesis and modification
rough endoplasmic reticulum
what are the two types of ribosomes
free ribosomes
fixed ribosomes
which ribosome produces proteins for immediate use
free ribosomes
which ribosome produces proteins for secretion and are attached to an organelle (the rough ER)
fixed ribosomes
the two membranous system that is contiguous (next to or touching) with the nuclear membrane
rough and smooth ER
studded with ribosomes; synthesizes proteins to be secreted and for the plasma membrane
rough ER
lacks ribosomes; synthesizes lipids, and some hormones; involved in detoxification, high concentration in the liver
smooth ER
made up of chromosomes and chromatin, has both a double layer membrane and pores or holes that allow passage of RNA but not DNA
nucleus
located inside the nucleus and is the site of ribosome synthesis
nucleolus
how do chromosomes differ from chromatin
chromosomes are where the genes are contained, there are 46 individual chromosomes when the cell is dividing that line up during metaphase in mitosis, when a cell is not dividing they form a ball or mass of the those 46 chromosomes and that is called chromatin
“the post office of the cell” packages and sends off materials in vesicles
Golgi Aparatus
two vesicles that contain powerful enzymes that could damage the cell
peroxisomes
lysosomes
contain oxidative enzymes, involved in metabolism of amino acids and fatty acids and detoxification, come contain catalase to breakdown hydrogen peroxide
peroxisomes
contains digestive enzymes used for destroying bacteria, and large solutes, involved in autolysis and apoptosis.
lysosomes
the “powerhouse” of the cell, site of ATP synthesis, has a double membrane, initiates apoptosis, contains DNA and self replicate
mitochondria
this part of the mitochondria increases surface area for reactions
cristae
________ or Deoxyribonucleic Acid, double stranded molecule that is spiraled like a staircase, each step of the staircase is made of a molecule called a _________.
DNA / nucleotide
composed of a sugar deoxyribose, a phosphate and a nitrogenous base. Phosphates lie on the outside of the molecule and the nitrogenous base are in the middle of the molecule.
Nucleotides
what are the 4 nitrogenous bases of DNA and how do they pair, also what is this pairing called?
adenine, guanine, cytosine, thymine
A&T, C&G, complimentary base pairing
_______, or ribonucleic acid, is another nucleic acid and is synthesized from DNA.
RNA
This nucleic acids jobs is to create proteins, which in turn can have a structural or functional role in the body.
RNA
Define the three steps of transcription
1>starts at the promoter (which signals the gene that it needs to be copied)
2>RNA nucleotides bind to their complimentary DNA pairs (A&T, U&A, C&G) via RNA polymerase.
3>The mRNA transcript is released from the DNA at the terminator.
This is the process of converting the DNA message into an RNA message known as mRNA or messenger RNA, analogous to you copying your biology notes from the PowerPoint into your handwriting.
Transcription
This is the process of turning the RNA message into a protein, the sequence of RNA determines the protein that is made, like turning a paper that is written in Japanese to one that is written in English
Translation
where does transcription occur
in the nucleus
where does translation occur
in the cytoplasm on the ribosome
a sequence of 3 nucleotides that encodes a particular amino acid,
Codon
The order in which the codons are arrange dictates the ________ formed.
protein
what are the steps of translation?
1>tRNA binds to the start codon
2>the ribosome assembles
3>another tRNA pairs with the next codon
4>The two amino acids are linked together via a peptide bond
5>the first tRNA leaves the ribosome while the second shifts over to make room for the next tRNA
steps 3-5 repeat until…
6>protein synthesis stops when the ribosome reaches the stop codon, at which time the completed protein detaches from the final tRNA.
what type of bond link amino acids together during translation?
a peptide bond
what happens during the first growth phase of interphase
the cell grows and performs its daily functions
what happens during the synthesis phase of interphase
DNA replication occurs
what happens during the second growth phase of interphase
final preparation for mitosis
describe the makeup of tRNA or the translator RNA
one end contains the Anticodon, the complimentary sequence of the mRNA, this matches up with
The other end which carries a specific amino acid
what are the three differences between transcription and translation?
Location
starting materials
products
what is the location, starting materials, and products in transcription?
location > nucleus
Materials > DNA
Product > RNA
what is the location, starting materials, and products in transcription?
Location > Ribosome
Materials > RNA
Product > Protein
The division of the cell, specifically the nucleus, which has 4 phases.
mitosis
what are the 4 phases
prophase “preparation”
metaphase “middle”
anaphase “apart”
telophase “together”
chromatin condenses to form chromosomes, nuclear membrane breaks down, and nucleoli disappear, mitotic spindle forms and attaches to the centromere of the chromosomes and maneuvers the chromosomes during mitosis.
prophase
chromosomes line up on the metaphase plate , ensures that the chromosomes will be evenly and properly divided amongst the two daughter cells
metaphase
the sister chromatids are separated, and move to opposite ends of the poles.
anaphase
the nuclear membrane reforms, the chromosomes unwind back into chromatin and nucleoli reappears
telophase
one half of a chromosome, an exact copy of DNA
sister chromatid
Center of the chromosome where the mitotic spindle attaches.
centromere
made up of microtubules, attaches to the centromere, and maneuvers the chromosomes during mitosis (prophase)
mitotic spindle
the name of the site where the chromosomes line up during metaphase
metaphase plate
division of the cytoplasm, begins toward the ends of mitosis in telophase
cytokinesis
_________ forms, microfilaments form a contractile ring that pinches the cell in half, always perpendicular to the mitotic spindle during _________.
cleavage furrow / cytokinesis
