Everything since the last lecture exam up until the end of the course Flashcards
What is the major function of the circulatory system for the body?
Transport materials
(highways)
What type of tissue if blood?
Liquid/ Fluid (connective tissue)
What is the heart?
Hollow muscular pump
What is blood made out of?
55% plasma (extracellular matrix) (water is 90% of plasma) (protein fibers and ground substance)
45% blood cells (red erythrocytes/white leukocytes, cell fragments platelets)
Where do blood cells originate from?
Red bone marrow.
Created by mitosis from our stem cells within the red bone marrow
What do stem cells differentiate into?
White blood cells, red blood cells, platelets
What happens to the blood once it matured in the red bone marrow?
it enters the blood stream
Fancy name for red blood cells? and how big are they? what shape do they have?
Erythrocytes (smallest cell in the body) 5um
Biconcave disk shape
What in the blood cells determines the blood type?
The antigens that are on the surface of the cell
What is the main function of erythrocytes?
Transport oxygen
Why do erythrocytes not have nuclei?
no nucleus= more room for oxygen carrying hemoglobin
Fancy name for white blood cells?
Leukocytes
Fancy names of platelets?
Thrombocytes (small cellular fragments)
What do thrombocytes do?
Aid in blood clotting. they see tears in collagen fibers of torn blood vessels and the platelets activate and glue or plug the tear
What does the hemoglobin do in red blood cells?
with the help of Iron (Fe), hemoglobin proteins stabilize oxygen (O2)
What type of muscle surrounds blood vessels?
Smooth
Compare the look of leukocytes and erythrocytes
Erythrocytes are more abundant. they are smaller and look like disks. no nucleus
Leukocytes are larger and they’re are less of them. they also have a nucleus
What is the main function of leukocytes?
To identify and destroy toxins and damaged or damaging cells. Immune response
What materials do red blood cells transport?
NUTRIENTS (from intestines to other tissues)
CHEMICAL SIGNALS (hormones from endocrine organs)
IMMUNE CELLS (from lymphatic organs)
CHEMICAL WASTE (CO2, metabolites - from tissues to excretory organs
and oxygen
What do blood vessels do?
Carry blood to and from the heart
What do arteries do?
Carry blood AWAY from the heart
What do veins do?
Carry blood BACK to the heart
What do capillaries do?
Allow for diffusion between blood and tissues. (like a school drop off)
Structure of arteries
Much narrower than veins (the more narrow the more pressure).
Thick layer of muscle that can contract to increase pressure (vasoconstriction)
What are the smallest arteries called?
Arterioles
Structure of Veins
Veins are wide (low pressure). have valves to prevent back flow.
What are the smallest veins called?
venules
What are capillaries?
They connect arterioles and venules. a web of tiny tiny vessels. so small only a single blood cell can fit through at a time. Capillaries are made of a single layer of simple squamous (for simple diffusion)
WHat type of cells are capillaries made of?
Capillaries are made of a single layer of simple squamous (for simple diffusion)
What are capillaries?
They connect arterioles and venules. a web of tiny tiny vessels. so small only a single blood cell can fit through at a time.
What are the 2 circuits of the heart?
1) pulmonary (lungs)
2) systemic (body)
What are the 4 chambers of the heart?
Left and Right Atrium (atria pl)
Left and Right Ventricles
What are the ventricles separated by?
SEPTUM
What side of the heart is deoxygenated and what side is oxygenated?
Right side (deoxygenated)
Left side (oxygenated)
What blood vessel brings deoxygenated blood from the upper body to the heart? and to what chamber does it bring it to?
Superior vena cava brings deoxygenated blood from the upper body to the right atrium
What blood vessel brings deoxygenated blood from the lower body to the heart? and to what chamber does it bring it to?
Inferior vena cava brings deoxygenated blood from the lower body to the right atrium
Where does the right ventricle send blood to?
pulmonary truck –> pulmonary arteries
Where does the left ventricle send blood to?
Aorta
What blood vessel brings oxygenated blood from the lungs to the heart? and what chamber does it bring it to?
Pulmonary veins bring oxygenated blood from the lungs into the left atrium
What are the names of the valves that are between the artia and the ventricles?
Atrioventricular valves (AV valves)
What is the name of the valve that sits between the right ventricle and the pulmonary trunk?
Pulmonary (semi-lunar valve)
What is the name of the valve between the left ventricle and the aorta?
Aortic (semi-lunar valve)
What type of muscle is in the heart?
Cardiac muscle
Tell me some shit about cardiac muscle
1) it contracts on its own (no use for neural stimulation)
2) highly branched and has intercalated discs between the cells
What are intercalated disks?
little disks between the cells that allow for coordinated contractions of the chambers
What is the “pacemaker” of the heart?
Sinoatrial node (SA node).
Found in the right atrium. It sets the pace for the muscular contractions. Sends signals to the left atrium so both atria can contract together
What is the 2nd node in the heart and where is it?
Atrioventricular node (AV node). Delays the signal from the SA node before sending it out to the ventricles. The ventricles then contract together AFTER the atria does. Near bottom on right atria*
What is the coordinated contraction of the heart called?
Systole
What is it called when the chambers in the heart are at a state of “relaxation”?
Diastole
What is blood pressure?
The force that the blood exerts on the walls of the blood vessels .
Ventricular systole over ventricular diastole. 120/80 mmHg
name of that thing that tests your blood pressure
Sphygmomanometers
What is your pulse?
The speed of the rhythmic stretching of the arteries during ventricle systole.
What happens if your blood pressure is too low?
Baroreceptors in your aorta will send signals to your brain to speed up your heart and to contract the arteries.
What happens when blood pressure equalizes?
baroreceptors will stop sending signals (negative feedback)
What do pedigree charts determine?
patterns; they are created to demonstrate the inheritance pattern of a particular trait down a family line
What is autosomal recessive inheritance?
child inherits one copy of each gene from parents (who do not show the gene)
trait cannot be dominant
PARENTS MUST BE HETEROZYGOUS
Xx Xx
2 unaffected parents have an affected offspring
What is autosomal dominant inheritance?
child inherits one copy of a gene from one parent
trait cannot be recessive
PARENTS MUST BE HETEROZYGOUS
Xx Xx
A child who has a parent with the mutated gene has a 50% chance of inheriting that mutated gene
What is complete dominance?
a form of dominance wherein the dominant allele completely masks the effect of the recessive allele in heterozygous conditions
what is incomplete dominance?
a form of dominance where neither allele is dominant
the alleles are usually both written as capital letters
i.e. flowers: RR (red), RW (pink), WW (white)
what is a genotype?
the specific combination of alleles that an individual possesses for a particular gene
i.e. for flower colour, pea plants could be PP, Pp, or pp
what is a phenotype?
the physical expression of those alleles
i.e., Pea plants that are PP or Pp have purple flowers, pea plants that are pp have white flowers
What is an intermediate phenotype?
when a heterozygote displays a phenotype that is one allele from each homozygous parent (one is homozygous dominant - XX and one is homozygous recessive - xx )
Xx
a demonstration of partial or incomplete dominance
What is the genotypic and phenotypic ratio for the offspring of a cross between two heterozygotes?
genotypic and phenotypic ratio of 1:2:1
What is the genotypic and phenotypic ratio for the offspring of a cross between two heterozygotes?
genotypic and phenotypic ratio of 1:2:1
What is co-dominance?
where both alleles are dominant and will be expressed
Both allelesare written as capital letters, or as super script letters on a capital letter
A heterozygote will express both alleles
I A I B (BLOOD)
What is the difference in the outcome of incomplete dominance and codominance?
Incomplete dominance results in blended intermediate phenotype in heterozygotes, while co-dominance results in both alleles being equally expressed
What is an example of co-dominance?
blood groups
What do the different blood types mean?
An individual’s blood group relates to what antigens (proteins)they have on the surface of their red blood cells
What are the four possible blood groups (phenotypes)?
O, A, B, AB
WHat are the three potential alleles for the blood group gene?
IA, IB, and i
WHat alleles for the blood group gene are co-dominant to each other? Which are completely dominant?
IAand IBare co-dominant to each other. If they are both present, they will both be expressed
IA and IB are both completely dominant to i. To express i, IAand IB cannot be present
What are the possible genotypes and phenotypes for blood groups?
ii= type O (no antigens)
IA IA orIA i= type A (A antigens)
IBIB or IBi= type B (B antigens)
IAIB = type AB (both A and B antigens)
What are sex-linked genes?
genes that are found on the X chromosome
What type of inheritance pattern do sex-linked traits follow?
XX/XY
Males will always express an X-linked trait
Males either donate an X or a Y to their offspring
Females have two copies of X-linked traits
Females always donate an X to their offspring
What is colour blindness an example of? What are the genotypes for females and males?
colour-blindness is a recessive sex-linked trait where at least one dominant allele will prevent colour-blindness
Females can either be:
XNXN (not color-blind)
XNXn (not color-blind)
XnXn (colour-blind)
Males can either be:
XNY (not colour blind)
XnY (colour blind)
What is the law of independent assortment?
For many genes, the inheritance pattern of one will not impact the inheritance pattern of another
For example, pea plants have multiple independent genetic traits; none will impact the expression or inheritance of the other
How many gametes will there be when considering the inheritance pattern of two genes?
four gametes
Each allele will separate independently of the alleles from another gene (independent assortment in anaphase I of meiosis)
What is the two gene blood type example?
In addition to the A, B, and O groups, blood cells also have the Rhesus factor (Rh positive) or lack the Rhesus factor (Rh negative)
The D allele codes for Rh +, while the d allele codes for Rh –
This means that there are two genes that impact your complete blood type (AB-, O+, etc.)
What is epistasis?
genes can influence the expression of each other
even though two genes are inherited independently of one another, one gene will impact the expression of the other
EX: Labrador puppoes
when you have a dominant allele
What is a polygenic trait?
single traits governed by more than one gene
e.g. eye colour, skin colour, blood pressure, height
What is a gene and how does it relate to a protein?
A gene is a segment of DNA that can be transcribed and translated into a protein
What are the two steps involved in protein synthesis (aka gene expression)?
transcription, translation
What is gene expression?
when a gene is transcribed and translated into a functional protein
What is gene regulation?
the process of altering how, or if, that gene is expressed
Why is gene expression tightly regulated?
Different cells in our body may express different proteins, even though they have the same DNA
What are the different ways that genes can be regulated? (what levels of protein synthesis can gene regulation occur at)
Epigenetic level, transcriptional level, post-transcriptional level, translational level, post-translational level
What happens at the epigenetic level of gene regulation?
genes permanently turned off
What happens at the transcriptional level of gene regulation?
genes prevented from transcribing
What happens at the post-transcriptional level of gene regulation?
mRNA processing
What happens at the translational level of gene regulation?
mRNA stabilizing
What happens at the post-translational level of gene regulation?
protein stabilizing
What happens if a change occurs upstream of the protein synthesis process and what one of the two types of protein synthesis does this affect?
its effect will be more widespread and will last longer; transcriptional
What happens if a change occurs downstream of the protein synthesis process and what one of the two types of protein synthesis does this affect?
its effects will be moreimmediate;
translational
What are histones and nucleosomes?
histones are proteins; when genes are not in use they are usually wrapped up in histones, which are further wrapped into nucleosomes
What is epigenetic regulation?
when the cell will modify the histones or the DNA itself to prevent them from being accessed; Typical modifications are adding methyl groups (DNA methylation)
What happens to genes when the histones are modified or the DNA itself?
typically inaccessible and thus permanently “turned off”
How long does epigenetic regulation last for? why?
generations; If the DNA itself is methylated (DNA methylation), these genes are permanently shut off and all daughter cells will have them “turned off” too (cell differentiation!)
What is cell specialization?
epigenetic regulation; each cell in your body contains the same DNA, but certain parts of their DNA are permanently modified during cell differentiation, resulting in specialized cells
What is X-inactivation?
Epigenetic regulation; In female (XX) tortoise-shell cats that have different alleles for fur colour, some cells will shut off one chromosome while others will turn off the opposite, leading to theirpatches
Is epigenetic regulation heritable? if so, why?
Environmental factors (diet, stress, trauma) can impact the epigenetic regulation of various genes in our cells
If this regulation occurs in our gametes, it will be passed on (intergenerational impacts)
What are transcriptional factors and what do they do?
If a gene is not packed, its transcription can still beregulated
Regulatory proteins called transcription factors can bind to genes
When a transcription factor binds to a target DNA sequence, it either promotes or reduces the transcription of that sequence
What are activators and what do they do?
Activators are transcription factors that activate transcription
E.g. in humans, activators promote the transcription of cytokines (chemical messengers) in the inflammation response
The DNA site bound by the activator is referred to as an “activator site”. The part of the activator that makes protein–protein interactions with the general transcription machinery is referred to as an “activating region”
What is a repressor in a prokaryote? idk sorry lol
In bacteria, the gene that codes for lactase (an enzyme that will break down lactose) is transcriptionally regulated
When there is no lactose present, a repressor binds to the operator region of the gene and no lactase mRNA is produced
In the presence of lactose, the repressor will bind to lactose molecules, leaving the operator site and allowing the gene to be transcribed
What happens to mRNA before translation?
mRNA is processed; If the RNA is successfully transcribed, it must be processed in the nucleus before being sent to a ribosome for translation
RNA processing includes:
- Removal of any introns
- Splicing together of the remaining exons
What does RNA processing include?
removal of any introns, splicing together of the remaining exons
WHat does post-transcriptional regulation involve?
alternative RNA splicing
What is alternative RNA splicing?
exons are spliced together in different combinations, producing more than one type of polypeptide from a single gene
How many exons does a typical human gene have?
ten exons
What does translational regulation involve?
mRNA stabilization
What is mRNA stabilization?
Recall that further RNA processing will help stabilize the mRNA once it leaves the nucleus:
Addition of a cap, coat, and tail to the RNA
mRNA life span (aka Like transcription,mRNA degradation)will affect how many times it will be translated
The length of poly-A tail is often indicative of the stability of mRNA and how often it will be translated
What is added to RNA during mRNA stabilization?
a cap, a coat, and a tail
What is an example of translational regulation?
mRNA for casein, the major protein of milk, has half-life of 1.1 hours in rat mammary gland tissue
During periods of lactation, presence of hormone prolactin increases mRNA half-life to 28.5 hours, resulting in more casein (lengthened poly-A tails!)
What are microRNA (miRNA)?
MicroRNA are small RNA molecules that bind completely or partially to mRNA to either induce mRNA degradation or block mRNA translation
What is an example of miRNA action?
miRNA molecules in respiratory epithelial cells act as antiviral defenses against influenza A viruses (Peng et al., 2018)
Useful for designing miRNA-based therapies against viral infection
miRNA -> prevents translation
No viral proteins created
What is activation and inactivation in post-translational regulation?
Activation: often involves cutting polypeptides into smaller, active final products
Inactivation: selective breakdown of proteins byproteasomes
What are cells?
Individual units of life
Come in many shapes and sizes in the body
WHat are tissues?
Many cells working together
WHat are organs?
several tissues together
What are organ systems?
several organs working together
What is epithelial tissue?
Epithelial tissue covers all body surfaces, cavities, hollow organs, and glands
Epithelial tissue is made of tightly packed epithelial cells
What are the different types of epithelial tissue for?
Protection (e.g., skin)
Sensation (e.g., receptors)
Absorption (e.g. intestines)
Secretion (e.g., kidneys)
Diffusion (e.g., capillaries)
What are the different shapes of epithelial cells and what are their functions?
Thin cells (squamous cells) are useful for diffusion
- Look like flat fried eggs
Cube-shaped cells (cuboidal cells) are good for secretion
- Look like cubes
Tall cells (columnar cells) are great for absorption
- Look like columns (nuclei stretched)
WHat are the different layers that epithelial tissue comes in?
Epithelial tissues can be single layered (called simple) for easy diffusion/absorption
Epithelial tissues can have many layers (called stratified) for protection
We name epithelial tissue based on their layering and shape
What is connective tissue and what does it do?
Connective tissue (CT) is found in between other tissue types to anchor, cushion, and support them
CT is made of specialized CT cells and their secreted extracellular matrix
The matrix consist of protein fibers (collagen, elastin) within a groundsubstance (liquid, gel, solid)
What are the two subtypes of connective tissue?
proper and specialized
What is loose connective tissue and what are the 3 types? what do they do?
reticular, adipose, areolar
these CT types are primarily ground substance with fewer fibers
these types of CT cushion and insulate organs they are found in
What is dense connective tissue and what are the 3 types? what do they do?
elastic, regular, and irregular CT
These CT types are primarily protein fibers (elastin or collagen)
These types of tissues give strength and support
Where are loose and dense connective tissue found?
both in skin
What is specialized connective tissue and what does it do?
Specialized connective tissues can be supportive, such as cartilage and bone.
Cartilage and bone have strong mineralized ground substancesand the cells sit in small cavities within it.
Protein fibers are found within the matrix for added support.
What are the three types of cartilage tissue?
Hyaline, elastic, fibrous
Hyaline cartilage is the most common and is flexible yet strong
Elastic cartilage contains elastic fibers, giving it elasticity
Fibrous cartilage contains collagen fibers, making it compressible
Where can we find hyaline cartilage?
makes up our nose, rib ends, and the ends of ourlong bones, and our larynx
Where can we find elastic cartilage?
makes up our ears and epiglottis
Where can we find fibrous cartilage?
between vertebrae
Where can we find elastic connective tissue?
lungs and arteries
Where can we find regular connective tissue?
tendons and filaments
Where can we find irregular connective tissue?
under the skin
Where can we find reticular connective tissue?
lymphatic organs
Where can we find adipose connective tissue?
found around kidneys, under skin
Where can we find areolar connective tissue?
under skin
What type of cartilage is the trachea made of?
hyaline cartilage
Bone is the hardest connective tissue. What are the two types of bone?
Spongy and compact
What is the hardest connective tissue?
bone
What does bone do?
provide protection and support
What is the bone matrix made of?
it is mineralized and filled with collagen fibers
Where is spongy bone found?
on the inside of our bones
Where is compact bone found?
the surface of our bones
Where is bone found?
nasal conchae
What are fluid connective tissues?
Fluid connective tissues have liquid ground substances and few fibers and are meant for TRANSPORT of cells and molecules
What are liquid connective tissues?
Blood and lymph are liquid connective tissues(primary component of matrix is water)
WHat is muscle tissue and what does it do?
Muscle tissue consists of bundles of long, thin muscle cells that can contract, allowing for movement of/within organs.
What are the features of muscle cells that make them moveable?
Muscle cells are excitable (by hormones and neurons), extensible (can stretch), elastic (can recoil), and contractile (can shorten)
What are the three major types of muscle tissue?
skeletal, smooth, and cardiac (differ in their structure and excitability)
What is skeletal muscle?
connects to bones, voluntarily contracts
Is striated (protein fibers aligned and thus strong)
What is smooth muscle?
found in hollow organs, involuntary
Lacks striations
What is cardiac muscle?
only found in the heart, involuntary
Striated
Intercalated discs allow for synchronized contraction
What muscle is found in the esophagus?
smooth muscle
What is nervous tissue and what is its function?
Nervous tissue is made up of neurons (nerve cells) and their support cells (e.g., glial cells).
Most tissue types have nervous tissue within them.
Responsible for sending electric SIGNALS to and from organs by creating electrochemical gradients.
Send rapid signals
What does our immune system do?
protects and defends our body against pathogens