Human organization plus DNA Flashcards
what are tissues?
assembles of similarly specialized cells that perform a common function
four main group Soft tissues?
muscle tissues
epithelial tissues
connective tissues
nervous tissues
epithelial tissues are aka?
epithium tissues
what are epithelial tissues?
tightly packed tissues that form a continues surface that covers body cavities
external surfaces where epithelial tissues can be useful?
prevents injuries, infection and drying out
internal surfaces where epithelial tissues can be useful?
modified to assist the transport of molecules and secretion
what do you call an epithelium that secretes a product?
glandular
how can an epithelium be specified?
shape
whether it secretes or not
whether its internal or external
what’s the general purpose of connective tissues?
acts as filler tissues
what are some(5) specific proposes of connective tissues?
binds organs together
fills space
provides support
stores fat
create red blood cells
are connective tissues made entirely out of cells?
no
what’s the material that’s linking the connective tissue?
matrix ( the other material present in connective tissues along with cells)
what is the matrix composed of?
non cellular material arranged on fibres containing collagen/elastin
3 ways matrix fibres can be grouped as?
white collagen fibres
reticular fibres
yellow elastic fibres
is blood considered as a connective tissue?
yes
if blood is grouped was a 5th type of tissue what would it be called?
vascular tissue
what’s the matrix of blood?
plasma
what do you call the arrangement of muscle tissue?
fibre like assembles called muscle fibre
how do the muscle fibre account it’s movement?
they have large amounts of actin and myosin filaments
what are the 3 types of muscular tissue?
skeletal muscle
smooth muscle
cardiac muscle ( a special type of smooth muscle )
what is the skeletal muscle attached to the skeleton by? it’s appearance and is its functions voluntary or involentary?
attached to skeleton by tendons
appearance is striated due to light and dark bands
functions voluntary
function of smooth muscle? appearance? is its functions voluntary or involentary?
functions to move substance across the body
appearance is not striated ( hence the name)
involuntarily functions
where is the cardiac muscle found? it’s function? appearance and is it involuntary or voluntary?
found in the heart
function is pumping blood
appears striated
functions involuntary
what is the nervous tissue cells composed of?
specialized cells called neurones
whats the function of nervous tissue?
relay stimulus info from one part of the body to another in the form of nerve impulses.
integumentary system contain what organs?
skin
circulatory system contain what organs?
heart, blood vessels
lymphatic & immune systems contain what organs?
lymph nodes
lymph vessels
lymphoid organs
digestive system contain what organs?
mouth
esophagus
stomach
small intestine
colon
liver
gall-bladder
pancreas
urinary system contain what organs?
bladder
kidneys
muscular system contain what organs?
bones
skeletal, smooth and cardiac muscle
nervous system contain what organs?
brain
spinal cord
endocrine system contain what organs?
hormonal glands
reproductive system contain what organs?
ovaries
penis
testes
vagina
what is homeostasis?
body’s ability to maintain a relatively constant internal temperature/ph etc.
some factors determining homeostasis?
pH
temperature
concentration of various chemicals
the primary mechanism that maintain homes stasis?
negative feedback
when does negative feedback occur?
when a change in the internal environment causes the body to deviate from the accepted homeostatic level.
what does the body create to balance a change of the body?
an effector
feedback loops will have the______ sensors and effectors involved in the process
same
when does an effector stop a process
when the body is no longer experiencing the change through negative feedback
what happens by the presence of an effector in positive feedback?
increased production of that effector.
4 types of diseases?
infectious
deficiency
hereditary
physiological
infectious diseases are caused by?
pathogens that can be transmitted
deficiency diseases are caused by?
insufficient molecule(s) in the body
hereditary diseases are caused by?
genetic mutations that run in the family
physiological diseases are caused by?
physical abnormalities within organ tissues
describe what a disease is?
sum of total problems associated with a specific condition
describe what a symptom is?
evidence of the disease
describe what a cause is ?
source of the disease
describe what a pathogen/infection is?
presence of a foreign body that might be a source
what are the molecules responsible for self replication?
nucleic acids ( RNA & DNA)
general description of RNA & DNA?
long chains of specific nucleic acids with the ability to bind themselves and each other, capable of encoding the info for protein production in a cell
3 part structure of RNA & DNA?
pentose sugar ( a five carbon ring shape)
Phosphate group
Nitrogenous base
pentose sugar in RNA vs DNA?
ribose and deoxyribose
how are nucleotides linked together?
phosphate group binding to it’s neighbouring pentose sugar
if described as a ladder, what molicules make up the sides of it and what is considered to be the “rungs” of it?
sides are considered to be sugar and phosphate groups
rungs are considered to be nitrogenous bases
what does the nitrogenous bases prominently feature?
nitrogen atoms in their composition
explain the stability of DNA in alkaline conditions
stable, as the nitrogenous bases are more closely packed and closed off from the environment (less exposed) than in the single staged RNA.
what’s the use of DNA vs RNA?
DNA - used to store and transfer genetic info
RNA - used as an intermediary and translator for the information that DNA encodes.
Where is DNA found?
in the cell nucleus
how does DNA exist during mitosis and what is it called?
exist as long, loose strands called chromatin
what is chromatin made up of?
long sequence of DNA wrapped around groups of proteins called histones.
what are nucleosomes?
DNA wrapped around histones
what happens to the chromatin during mitosis? and why?
it compacts and condenses into chromosomes, which allows more simplifies means of separating and accounting for all the DNA.
chromatin?
lots of neucleosomes together
what are genes?
the regions of DNA that code for the production of proteins needed for a specific metabolic task
a gene has around _____ base pairs and there are around _____ genes on a single chromosomes
1000
175,000
roughly how many genes do we have?
8 million
how many chromosomes do humans have?
46
chromosomes in pairs are called?
homologous chromosomes
homologous chromosomes code as the _____ gene as each other. variations between these two are called??
same
alleles
genes responsible for features of the body are called?
traits
what leads to variation in traits?
variation of alleles
abnormalities in chromosome numbers can lead to???
genetic disorders
what’s the abnormality in TRISOMY 21?
(Down syndrome) there is an extra pair of chromosomes, total 47
what’s the abnormality in CRI DU CHAT ?
deletion of the part of the 5th chromosome
what’s the abnormality in 45 XO
turner syndrome, full deletion of the second sex chromosome
how many chromosomes determines sex?
1
the egg has ___ chromosome and the sperm has ____?
x
x or y (which determines gender)
variations in the sex chromosomes of individuals?
XXY ( Klinefelter, 0.17% males)
XXX ( Trisomy X, 0.1% females )
XYY ( Jacob’s, 0.1% males)
X ( Turner, 0.05% females)
Y non viable fetus
use of helicase?
unzip DNA double strand by breaking hydrogen bonds for transcription and zip it back after.
use of RNA polymerase?
transcribes the DNA according the their complimentary base pairs in the unzipped DNA. forms a strand of mRNA carrying the DNA’s instructions.also adds a ribose sugar and a phospahte group to create the backbone of the RNA
what adds the ribose sugar and phosphate group to create the backbone of the RNA strand?
DNA polymerase
how does mRNA leave the nucleus ?
through nuclear pores.
2 important things to note about the newly created RNA in transcription?
the strand will be complimentary base of the template strand, “opposite” of the DNA.
URACIL will be in the place of thymine, binding with adenine.
3 nucleotide sequences are called?
codons
what is redundancy when considering the composition of codons?
the fact that there are multiple codon sequences to get a specific amino acid.
what are introns?
the spaces in the transcribed mRNA, that needs to be removed for the final product
what are exons?
the remaining portion of mRNA after the introns have been removed, the part that gets translated.
what removes intrones and bind exons?
enzymes
after the removing and the binding of introns and exons, what happens to the mRNA?
A “cap” made of modified guanine nucleotide is fixed to one end. along with a poly A tail made up of adenine nucleotide is fixed to the other end.
the modification process of mRNA is called?
mRNA processing
importance of introns?
they are used to create multiple sequences from the same initial sequence
what needs to happen for any mRNA that leave the nucleus?
translated into an amino acid and eventually a functioning protein
where does the translation of protein take place?
rRNA ( ribosomal RNA)
the function of rRNA?
act as binding sites where translation happen. codons are read and translated to the appropriate amino acids.
function of tRNA?
carry appropriate amino acids to the developing sequence. they bind to the correct mRNA codon to transfer the complimentary amino acid.
3 facts about tRNA?
typically shown as a cross shape with 3 loops
amino acid (that it carries) is attached to the top
the anticodon ( complimentary bases to the codon) is located at the bottom end )
the portion of the tRNA where amino acids bind needs what?
ATP
3 steps in translation
initiation
elongation
termination
describe initiation
START codon of the mRNA binds to the small subunits of the ribosomes then to the larger one.
describe elongation
creation of a polypeptide chain via dehydration synthesis. each ribosome has 3 binding sites
describe termination
STOP codon of the mRNA is read and the 2 subunits if rRNA fall off the mRNA sequence. the produced polypeptide chain is cut away by hydrolytic enzymes.
what can happen to a fully synthesized protein?
can further fold
can be store
can be combined with other molecules
can be transported outside of the cell
what are polysomes? and why are they there?
ribosomes that read the same mRNA and create the same polypeptide chain, they increase the efficiency of the protein production
where are rRNA’s created?
created from DNA in the nucleus.
the protein section of it form in the cytoplasm
DNA is considered semi-conservative, why?
because each helix produced conserves one half of the original double helix
what ensues the production of 2 identical copies and DNA double helix?
the complimentary base paring of DNA
order of DNA transcription and translation
DNA helices unzips
DNA polymerase reads and creates mRNA strand
it is refined and the mRNA is processed
it leaves the nucleus and binds to a rRNA
which act as a binding site where it reads the mRNA and pairs it with the correct tRNA
termination, makes the rRNA fall apart
the newly created polypeptide chai is cut away by hydrolytic enzymes
Okazaki fragments ?
the addition of piece by piece mRNA in the lagging strand
what connects the Okazaki fragments?
DNA ligase
damages in the DNA are called?
mutations
frequency of mutations during DNA replication?
1 mistake per billion nucleotide pairs replicated
mutation occur due to _____ and happen due to what?
environmental conditions
harmful influences called mutagens
disorders can result in mutation that occur in the ____or the ____ cells
germ cells (gametes)
somatic ( non-gamete)
two variations that can happen to proteins due to mutations ?
non functional proteins are created
new protein may be produced
mutations become more common with ____?
age
cancer is? simply put?
uncrossed cell growth (tumours)
3 factors that enable cancer?
the suppressor genes turned off
cell division genes turned on
unresponsive to apoptosis ( cell death signals)
initial stage of cancer?
abnormal/irregular but harmless cell growth (benign)
how do benin tumors become harmful?
by undergoing more mutations and becoming malignant
4 general characteristics of cancer?
does not undergo apoptosis
does not regulate according the cell cycle
are genetically unstable
can survive and proliferate in various ares and conditions within the body.
cancer that spread to additional regions of the body is____?
metastasized
underwent metastasis
why are tumors so hard to remove?
as they can supply itself blood by forming it’s very own blood vessels through angiogenesis. angiogenesis gets the tumour acces to the body’s resources.
general treatments for cancer?
chemotherapy
radiation therapy
surgery
what is recombinant DNA?
DNA contained from 2 or more different sources.
advantage of recombinant DNA?
insertion of these specifically selected genes into another organism makes it create proteins it didn’t before
( insulin producing genes in bacteria)
what is polymerase chain reaction?
copying of DNA segments in large quantities
advantage of polymerase chain reaction?
tiny quantities of DNA can be taken and amplifies into large amounts for analysis
what is Gene therapy?
insertion of specifically selected genes into an organism to Treat a disorder that stems from protein deficiency.
