BIOL 161 Exam 4

Flashcard

Learn Mode

Match

Library

Create

Flashcards

Library

Match (Coming Soon)

Biology - Anatomy

user_pereira_de_andr Created by 9 mon ago

Cards in this deck(100)

individual muscle cell

group of muscle cells (fibers)

plasma membrane of skeletal muscle cells

the cytoplasm of a skeletal muscle cell

contractile unit of a muscle cell that makes a myofibril (made of thick and thin filaments)

modified endoplasmic reticulum that regulates calcium in the cell; storage location for calcium

tubes continuous with the sarcolemma to increase surface area

major component of muscle cell (takes up the most intracellular volume)

oxygen-binding protein in a muscle cell

contains many nuclei

fibrous connective tissue that is continuous with the tendon

skeletal and cardiac

muscle = made of fascicles = made up of muscle fibers (cells) = made up of myofibrils = made up of sarcomere = made up of protein filaments

protects muscle cells, reduces friction, creates space for extracellular fluid

epimysium, perimysium, endomysium

covers entire muscle; outermost layer

covers fascicles

covers muscle fibers

muscle to bone; collagen fibers of epimysium form strong tendons that merge into outer coverings ove bone

Attaches muscle to bone; made up of dense regular connective tissue

muscle to bone / indirect

muscle to muscle; collagen fibers are directly continuous with periosteum; muscle emerges directly from bone

muscles insert to broad sheet of connective tissue called an aponeurosis

strong sheet of tissue that acts as a tendon to attach muscles to bone; broad and flat

circular, convergent, parallel, pennate, fusiform

fascicles concentrically arranged around an opening - ex. mouth

fascicles from a broad area converge on a common attachment - ex. pectoralis major

fascicles parallel to long axis of muscle; sartorius

fascicles attach at an angle to a central tendon

excitability, conductivity, contractility, elasticity

ability to respond to stimuli; responds to chemicals released from motor neurons

ability to propagate electrical signals over membrane; conduct charge

ability to be stretched without damaging the tissue

ability to return to original shape after being stretched

skeletal

smooth, cardiac

smooth

skeletal

cardiac, smooth

attached to bone or fascia; looks like lines; distinct dark and light regions; long/cylindrical

autorhythmic (self-regulate); branched

blood vessels; line walls of hollow organs

myosin

can bind and hydrolyze ATP

actin, troponin, tropomyosin

has an active site that can bind to the head of a myosin protein

binds and regulates tropomyosin; in the presence of calcium it moves tropomyosin off of active sites; BINDS TO CALCIUM

covers active actin sites when muscles are relaxed

only thin filaments

only thick filaments

boundary between sarcomeres

midline of sarcomere

contains M line

stores oxygen for use

thin filaments move toward the center of the sarcomere causing sarcomeres to move closer together and cause muscle contraction

sarcomere shortens, H zone disappears, I band shortens, A band stays same size

actin, elastin

they do not move

synapse between a motor neuron and a muscle cell

sarcolemma region associated with the neuromuscular junction; contains chemically-gated ion channels

neurotransmitter released into the neuromuscular junction

excitation, excitation-contraction coupling, contraction, relaxation

communication between neuron and muscle cell leads to an action potential

conversion of action potential in muscle cell to activation of proteins in the sarcomere

sliding filament theory

return of muscle cells to resting length

bind to acetylcholine the the post-synaptic membrane

motor end plate

breaks down acetylcholine in the synaptic cleft

cation chemical gated channels (K or Na)

Release of cross-bridge (interaction) between actin and myosin; Movement of calcium ions back into the sarcoplasmic reticulum after contraction ends; Conformation change of myosin from the bent conformation to the extended (activated) conformation.

sarcolemma

Cross-bridges would form in the absence of an action potential from a motor neuron.

active transport protein found in SR

sarcolemma

diffuses out of SR into the sarcoplasm

actin and myosin

Release myosin from actin active sites; To cause myosin to change shape to the cocked (extended) position.

less

At rest, the H-band is about half the length of the A-band

depolarizes / excites sarcolemma

1. action potential from motor neuron 2. secretion of ach hormone into synaptic cleft (creates end plate potential) 3. end plate potential triggers an action potential sarcolemma

ca voltage gated channel allows ca to enter cell and secrete into the synaptic cleft

chemically gated ach receptors lead to depolarization of end plate potential voltage gated cation channels propagate action potentials

translate depolarization of sarcolemma into changes of proteins

1. action potential travels down T-tubule 2. Ca voltage gated channels connected to mechanically gated Ca channels open 3. Ca diffuses into sarcoplasm 4. actin's binding sites revealed

ca voltage gated channels open

ca mechanically gated channels open and diffusion of Ca into sarcoplasm

troponin binds to ca tropomyosin - changes shape / moves off of the myosin binding site on actin actin - ready to bind to myosin

shorten the sarcomere so the muscle can shorten; cross-bridge cycle

1. myosin hydrolyzes ATP into ADP and P; myosin extends 2. myosin binds to actin = cross bridge formation 3. ADP + P released and myosin head flexes; thin filament pulled towards m-line; sarcomere shortens (sliding filament theory) 4. ATP binds to myosin and cross bridge breaks

stop contraction, return sarcomere to resting length

1. action potentials from somatic motor neuron stop 2. secretion of ach stops; ach broken down by ache; no more muscle exciton = no more end plate potential 3. ca pumped back into SR - cross bridge can no longer form; tropomyosin covers binding site again

ache breaks down ach

ca pumps use ATP to pump ca back into the SR

Ask Our AI Tutor

Get Instant Help with Your Questions

Need help understanding a concept or solving a problem? Type your question below, and our AI tutor will provide a personalized answer in real-time!

How it works

Ask any academic question, and our AI tutor will respond instantly with explanations, solutions, or examples.

Get Started

Browse questions and discover topic-based flashcards
Practice with engaging flashcards designed for each subject
Strengthen memory with concise, effective learning tools

Discover By Topic

BIOL 161 Exam 4

Related Decks