MCB 32 Midterm 1

organ system that provides communication within the body by releasing hormones into the bloodstream

endocrine

organ system that provides communication between cells in the body via electric signals

nervous

organ system that supports the body and allows voluntary and skeletal body movement

muscoskeletal

organ system that transports molecules throughout the body and is responsible for moving material

cardiovascular

organ system that takes in oxygen and expels carbon dioxide

respiratory

organ system that filters the blood to regulate acidity, blood volume, and ion concentrations; as well as excreting waste

urinary

organ system responsible for breaking down and absorbing food

gastrointestinal

materials in the external environment must pass through ? cells (? # of membranes) to enter the internal environment

epithelial, 2

the most total body water (internal) is in the

intracellular fluid (inside the cell)

two categories of extracellular fluid

plasma (most of ECF) and interstitial fluid

fluid that is not in the blood, but that surrounds cells

interstitial

the phospholipid bilayer can easily be permeated by which kind of molecules

nonpolar (hydrophobic)

an important storage polysaccharide found in animal tissues

glycogen

steroid structure

nucleotide structure

nucleotide: 5 carbon sugar + phosphate group + base (adenine, guanine, cytosine, thymine, or uracil)

amino acid structure

phospholipid structure

reactions that require energy input

endergonic

what type of reaction is the breakdown of polysaccharides into monosaccharides

hydrolysis, catabolic

T/F - enzymes are consumed in a reaction

FALSE (enzymes are NOT consumed in a reaction)

enzymes are what biomolecule

proteins

what does it mean to say that an enzyme is saturable

the rate at which an enzyme catalyzes a reaction depends on substrate concentration until a threshold concentration is reached

movement of ions across a membrane

neuronal signalling

molecules that release H+ ions when dissolved in water

acids

ph below 7

acids

ph above 7

bases

important characteristic of phospholipids

amphiphillic (polar and nonpolar)

what characterizes a peptide

less than 50 amino acids

function of nucleic acids

store and express genetic information (i.e. directions for making proteins)

proteins are made up of

amino acids

proteins act as ? to catalyze chemical reactions

enzymes

T/F: proteins can provide structural support for cells

true

nucleic acids are polymers of ?

nucleotides

the sum of all chemical reactions in cells

metablism

breakdown of large molecules into smaller ones

catabolism (exergonic)

production of larger molecules

anabolism (endergonic)

what type of reaction is disaccharide --> monosaccharide

catabolism (exergonic)

why are anabolic reactions able to happen in cells?

because they are coupled with catabolic reactions

the rate of a catabolic reaction can be increased/decreased by altering the ...

activation energy barrier

proteins that act as catalysts to speed up chemical reactions by lowering the activation energy

enzymes

substrates bind to enzymes in the ?

activation site

enzymes are NOT ? by reactions

CONSUMED

T/F: enzymes can catalyze multiple reactions

true

an enzyme that has a higher affinity for substrate A than for substrate B, will ??

bind faster to substrate A than B, however eventually both will bind to saturate all enzymes

how can you increase the rate of an enzymatic reaction when all enzymes are saturated?

add more enzymes

allosteric regulation binding is

reversible and noncovalent

allosteric regulators alter

enzyme affinity for substrates

where do allosteric regulators bind to enzymes

anywhere but the activation site

covalent modification (i.e. phosphorylation of enzymes) can alter

enzyme activity and affinity

a collection of cells with a related function

tissue

4 types of tissues:

epithelial, connective, nervous, muscular

a single layer of cells that act as selective barriers connected by tight junctions

epithelial tissue cells

transmembrane proteins that hold epithelial cells together preventing molecules from passing in between cells

tight junctions

side of epithelial cell facing the lumen

apical

side of epithelial cell facing the blood vessel

basolateral

on the apical side of an epithelial cell, there are ? that increase the surface area

microvilli

two types of epithelial glands

endocrine and exocrine

glands that secrete hormones into the blood stream

endocrine

glands that secrete products into the external environment (i.e. tears, sweat, digestive track materials)

exocrine

3 types of muscle tissue

smooth, cardiac, skeletal

only muscle tissue that is voluntary

skeletal

tissue that lines blood vessels and the digestive tract

smooth muscle tissue (pushes food through the body)

a lysosomal storage disease that causes a mutation of the nuclear envelope and accelerated aging

progeria

plasma membrane is made of

sugars, proteins, and lipids

two types of nervous tissues

neurons and glia cells

two organelles surrounded by TWO membranes

nucleus and mitochondria

transcription (DNA copied into RNA) occurs where

nucleus

the nucleus contains genetic information in the form of

chromatin (DNA + proteins)

the cytoplasm is made up of

cytosol and organelles

the ? structure surrounds the nucleus

endoplasmic reticulum

function of the rough ER

protein synthesis

function of the smooth ER

synthesizes lipids

translation occurs where

in the rough ER

process where RNA is read by ribosomes and used to make proteins

translation

organelle that receives synthesized proteins from the ER and finishes processing them, then packages them and delivers them to their final destination

golgi apparatus

how does the ER deliver proteins to the plasma membrane (exocytosis)

secretory vesicles

process in which the membrane of a secretory vesicle and the plasma membrane fuse to release contents outside of a cell

exocytosis

lysosome is surrounded by ? membrane(s)

1

function of lysosome

contains enzymes to digest debris/old organelles

T/F: mitochondria has its own DNA and can make cellular energy (ATP) via cellular respiration

true

chemical reaction that breaks down sugars/fats/proteins to yield ATP/water/carbon dioxide

cellular respiration (occurs in the mitochondria)

anaerobic respiration (glycolysis) occurs where?

cytoplasm

the cytoskeleton is made up of ? that provide cell structure/support

proteins

T/F: the cytoskeleton is not rigid/fixed

true (the proteins in the cytoplasm reassemble all the time!)

two components of the cytoskeleton

microtubules and microfilaments (actin)

component of the cytoskeleton that is usually found near the cell membrane, and involved in cell movement and muscle contraction (also found in microvilli)

microfilaments (actin)

largest filament of the cytoskeleton, provides a track for transporting vesicles

microtubules

makes up cilia/flagella

microtubules

involved in cell movement / muscle contraction

microfilaments

RBC's perform

anaerobic respiration (glycolysis)

number of glucose molecules produce in aerobic respiration

36

number of glucose molecules produced in glycolysis

2

the Na+/K+ pump is an example of what type of transport

primary active transport

sodium-linked glucose transport (couples the inward flow of sodium with the inward flow of glucose) is an example of what type of transport

symport (cotransport)

diffusion distance increases - what happens to the rate of simple diffusion?

decreases

can neurotransmitters diffuse across the plasma membrane

NO

intercellular communication occurs at

chemical synapses and gap junctions

the a ligand binds a GPCR, the gprotein releases a ? and binds a ?

GDP, GTP

a chemical messenger that acts on a nearby cell is functioning as a

paracrine signal

hypersecretion of ACTH would lead to the following

increased cortisol levels, decreased CRH levels