NUR3125 - Cell and Tissues PlayPosit

structure of eukaryotic cell

plasma membrane

nucleus - DNA & RNA

cytoplasm & organelles:

- ribosomes

- ER

- golgi apparatus

- mitochondria

difference between prokaryotic and eukaryotic cells?

eukaryotic has organelles (ribosomes, ER, GA, mitochondria)

plasma membrane function

regulates what comes in and out of the cell via phospholipid bilayer and its proteins

nucleus function

contains DNA and controls the cell

nuclear membrane function

separates the nucleus from the cytoplasm

ER function

protein synthesis and transport

lipid synthesis

smooth vs. rough ER

RER has ribosomes attached

mitochondrion function

undergoes cellular respiration to produce ATP/energy

golgi apparatus function

processing and packaging of proteins

microtubule function

maintenance of cell shape, cell motility, chromosome movements in cell division, organelle movements

apart of cytoskeleton of cell

ribosome function

protein synthesis

lysosomes function

digesting cellular substances

cytoskeleton function

"bones and muscle" of cells

name and describe the 8 cellular functions

1. movement - muscle cells generate forces

2. conductivity - nerve cells → electrical potential

3. secretion - mucous gland cells

4. excretion - cells rid waste products

5. metabolic absorption - cells take in and use nutrients

6. respiration - cells absorb oxygen and transform nutrients into ATP; cell respiration or oxidation

7. reproduction - grow tissue and replace cells

8. communication - vital to survive

what is energy metabolism? types?

chemical tasks of maintaining cellular function

anabolism and catabolism

anabolism vs catabolism

uses energy to build molecules

breaks down molecules (carbs, fats, and proteins) into energy needed for cell function

ATP

major source of cellular energy

aerobic vs anaerobic metabolism

presence of oxygen to produce energy

lack of oxygen in producing energy

types of membrane transport mechanisms

passive transport - diffusion (facilitated and passive) and osmosis

active transport

passive transport

the movement of substances across a cell membrane without the use of energy by the cell

diffusion + its types

a type of passive transport where there is a movement of solutes from an area of greater concentration to lesser without energy

facilitated: membrane protein facilitates the diffusion, such as glucose going from the outside → inside cell

passive: substances diffuses across the plasma membrane without proteins until it reaches equilibrium; includes oxygen, alcohol, and CO2

osmosis

passive diffusion that includes the movement of water down concentration gradient (high to low) across a semipermeable membrane

active transport + example

transport of a molecule across a plasma membrane against its concentration gradient (low → high) using energy and a membrane protein

ie. ATPase pump - NA+ molecule moves from inside → outside as there is a high concentration in the outside

K+ molecules move from outside → inside as its concentration is higher on the inside

tissues

groups of cells that are similar in structure and function

4 types of tissues

epithelial - covers most of internal and external body surfaces (simple squamous, transitional, stratified squamous epithelium, etc.)

connective - binds tissues and organs together (adipose cartilage, bone, blood)

muscle - composed of myocytes (striated, cardiac, and smooth muscle)

nervous - specialized cells, neurons, and glia

what is cellular adaptation?

change in cell structure and function due to its environment

cell atrophy vs hypertrophy

decrease in cell size (thymus gland, gonads, and disuse atrophy)

increase in cell size due to mechanical stimuli (hypertension → heart pumps blood harder → left ventricle hypertrophy → difficult to send blood to systemic circulation)

hyperplasia + examples

increase in # of cells

ie. part of liver removal → cells divide faster

metaplasia vs. dysplasia

replacement of one mature cell (smoking → columnar ciliated epithelial cells are replaced by stratified squamous epithelial cells → loss of protective mechanism)

abnormal changes in size, shape, and organization of mature cell but not a true adaptive change; does not indicate cancer and may not progress to cancer (epithelial tissue of the cervix)

benign vs. malignant tumors

remain at the original site

named according to the tissues from which they arise and include "-oma"

spread far beyond tissue of origins (known as metastasis) with a rapid growth rate and microscopic alterations

named according to the tissues from which they arise (carcinoma - epithelial, adenocarcinoma - ductal or glandular, sarcoma - mesenchymal, lymphoma - lymphatic, leukemia - blood forming cells)

carcinoma in situ

early-stage cancer, specifically pre-invasive epithelial malignant tumors of glandular/epithelial origin that have not broken through the basement membrane or invaded the surrounding stroma

causes of cell injury/death

physical agents - contusions, lacerations, fractures, incised wound, stab wound, puncture wound

radiation injury

chemical injury - over the counter and prescribed drugs

nutritional imbalances

hypoxic injury - shortage of oxygen; most common cause of CI; common cause of HI is ischemia

free radical injury - oxidative stress due to excessive reactive oxygen species

types of cell death

necrosis and apoptosis

apoptosis

programmed cell death/suicide either as a normal physiological or pathological process

examples of apoptosis as normal physiological processes

cells in embryonic process, endometrial cells during menses, breast tissue regression after breastfeeding

examples of apoptosis as pathologic processes

cases where there is too much or too little apoptosis such as Alzheimer's/ALS/Parkinson's, carcinogenesis, autoimmune disorders

which type of cell death is ONLY pathological? which can be both?

necrosis

apoptosis

necrosis + examples

cell death in an organ/tissue that is still alive (some cells may die but rest of tissue in organ remains to function)

cellular changes after local cell death include rapid loss of plasma membrane, swelling of organelles, enzymatic digestion of cell components, and inflammation

always pathological

coagulation, liquefaction, caseous, and fatty necrosis

gangrene

mass of tissue undergoing necrosis (dry or wet)

clostridium: gas gangrene infection of tissue by anaerobic bacteria

process of apoptosis vs. necrosis

condensation of chromatin → membrane blebs → cellular fragmentation →apoptotic body → phagocytosis of apoptotic cells and fragments

swelling of ER and mitochondria + membrane blebs → breakdown of plasma membrane, organelles and nucleus, leakage of contents, amorphous densities in mitochondria → inflammation → explosion in cell

chromosomes

threadlike structures made of condensed DNA molecules (chromatin) that contain the genes (23 pairs in humans)

how many chromosomes do gametes have and why

23

they are haploids → allows for the correct number of chromosomes to be restored when two gametes fuse during fertilization

diploids

2 sets of chromosomes/23 pairs

chromatin

DNA with proteins

genes

basic units of inheritance in the chromosomes; made up of DNA

building blocks of chromosomes

DNA → chromatin → chromosomes

homozygous vs heterozygous

loci (a specific location on a chromosome where a gene or genetic marker is found) on a pair of chromosomes that have identical alleles

loci on pair of chromosomes with different alleles

allele

different forms of a gene

DNA

(deoxyribonucleic acid)

double helix model made of nucleotides that codes for proteins

how info is processed

nucleotides → DNA → RNA → amino acids → proteins

mutation

alteration of genetic material

genotype

the genetic constitution of an individual organism.

phenotype

observable characteristics of an individual resulting from the interaction of its genotype with the environment

dominant vs recessive allele

allele that is observable

allele whose effects are hidden

autosomes

the first 22 of the 23 pairs of chromosomes in males and females

sex chromosomes

one of the 23 pairs of chromosomes in the human that will determine the sex

females - XX

males - XY

karyotype

the number and visual appearance of the chromosomes in the cell nuclei of an organism or species.

transcription

synthesis of an RNA molecule from a DNA template

translation

genetic information coded in mRNA directs the formation of a specific protein at a ribosome in the cytoplasm

chromosomes in zygote vs gamete

46

23

autosomal dominant inheritance

pattern of genetic inheritance where a copy of a mutated gene from one parent can cause a genetic condition in child; a way of inheriting a gene where 1 parent has the affected/dominant gene

in autosomal dominant inheritance, which sex offspring is affected?

male/female offspring affected equally

in autosomal dominant inheritance, if one of the parents is heterozygous affected, the children have a __% of being affected

(draw punnett square)

50%

in autosomal dominant inheritance, if both of the parents is heterozygous affected, the children have a __% of being affected

(draw punnett square)

75%

marfan syndrome

an autosomal dominant disorder whose primary causes are ocular (retinal detachment), skeletal (join hypermobility, spinal deformities, pigeon chest, long body), and cardiovascular anomalies (mitral valve prolapse and aortic valve disease)

autosomal recessive inheritance

two recessive alleles must be present for trait to be displayed

in autosomal recessive inheritance, what sex offspring is affected?

male/female affected equally

in autosomal recessive inheritance, if both parents are unaffected but are carriers for the trait, each offspring has a __% chance of being affected

(draw punnett square)

25%

in autosomal recessive inheritance, if both parents are affected, __% of their children will be affected

(draw punnett square)

100%

in autosomal recessive inheritance, if one parent is affected and the other is not a carrier, __ of their offspring will be ______ but will be ______

(draw punnett square)

all, unaffected, carriers

in autosomal recessive inheritance, if one parent is affected and the other is a carrier, each of the offspring will have a __% chance of being affected

(draw punnett square)

50%

cystic fibrosis

an autosomal recessive disorder due to the mutation in gene CFTR on chromosome 7

chloride transport decreased, affected organs in the GI, respiratory, and reproductive system

sweat test shows elevated chloride

phenylketonuria

an autosomal recessive disorder where there is an inability to convert phenylalaine to tyrosine, a precursor to melanin → mental retardation, elevated phenylalanine, fair skin, decreased melanin, ezcema

tay-sachs disease

an autosomal recessive disorder where there is a failure of lysosome function and thus an accumulaton of glycolipids → destruction of neurons in brain, SC, ANS → mental retardation and motor problems → blindness, seizures, and death

sex-linked inheritance

Inheritance of a genetic trait located on the sex chromosomes

most x-linked disorders are what and mostly affect who and why

recessive

male - females have another X to counteract/override the abnormal gene

in x-linked recessive disease, affected males cannot transmit the affected gene to ___ but they can to all _____.

(draw punnett sqaure)

sons, daughters

in x-linked recessive disease, sons of female carriers have __% risk of being affected

50%

causes of chromosomal disorders

alterations in the structure of one or more chromosomes with rearrangement/deletion of chromosome part

abnormal number of chromosomes

down's syndrome

chromosomes 21 has 3 copies instead of 2 (+1 chromosome)

risk increases with maternal age

protruding tongue, flat nasal bridge, small ears, metal retardation, heart problems

turner syndrome

a chromosomal disorder in females in which either an X chromosome is missing, leading to 45 chrosomes (-1)

short statue, webbing neck, lack of secondary sex characteristics, absent ovaries, coartctation of aorta and bicuspid aortic valve, some difficulty driving and nonverbal problem solving