Review Test2 NoFigs

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BSC2011. Review exam 2

From Neurons

to

Muscles and from

Plant structure to

Hormones

Martijn Slot, 08 July 2009

Road map:

Animal Form & FunctionChapter 48: Neurons, Synapses, and SignalingChapter 49: Nervous SystemsChapter 50: Sensory and Motor mechanisms

Plant Form & FunctionChapter 35: Plant Structure, Growth, and DevelopmentChapter 36: Resource Acquisition & Transport in Vascular PlantsChapter 37: Soil & Plant NutritionChapter 38: Angiosperm Reproduction & BiotechnologyChapter 39: Plant Responses to Internal & External Signals

Plant Form & FunctionChapter 35: Plant Structure, Growth, and Development

35.1 The plant body has a hierarchy of organs, tissues, and cells

35.2 Meristems generate cells for new organs

35.3 Primary growth lengthens roots and shoots

35.4 Secondary growth adds girth to stems and roots in woody plants

35.5 Growth, morphogenesis, and differentiation produce the plant body

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Which of the following is derived from the ground tissue system?

A) root hairs

B) cuticle

C) periderm

D) pith

E) phloem

Concept 35.1

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Plants contain meristems whose only function is to

A) attract pollinators.

B) absorb ions.

C) photosynthesize.

D) divide.

E) produce flowers.

Concept 35.2

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Shoot elongation in a growing bud is due primarily to

A) cell division at the shoot apical meristem.

B) cell elongation directly behind the shoot apical meristem.

C) cell division localized in each internode.

D) cell elongation localized in each internode.

E) A and B only.

Concept 35.3

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Cells produced by lateral meristems are known as

A) dermal and ground tissue.

B) lateral tissues.

C) pith.

D) secondary tissues.

E) shoots and roots.

Concept 35.4

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

According to the ABC model of floral development, which genes would be expressed in a showy ornamental flower with multiple sepals and petals but no stamens or carpels?

A) A genes only.

B) B genes only.

C) C genes only.

D) A and B genes only.

E) A and C genes only.

Concept 35.5

Fig. 35-34Sepals

Petals

Stamens

Carpels (a) A schematic diagram of the ABC hypothesisA

A + Bgene

activity

BC

A geneactivity

B + Cgene

activity

C geneactivity

Carpel

Petal

Stamen

Sepal

Activegenes:

Whorls:

StamenCarpel

Petal

Sepal

Wild type Mutant lacking A Mutant lacking B Mutant lacking C

A A A AB B B BC C C C

B B B BC C C C C C C C A A A AC C C C A A A AB B B B

A A A A

(b) Side view of flowers with organ identity mutations

Plant Form & FunctionChapter 36: Resource Acquisition and Transport in Vascular plants

36.1 Land plants acquire resources both above and below ground

36.2 Transport occurs by short-distance diffusion or active transport, and by long-distance bulk flow

36.3 Water and minerals are transported from roots to shoots

36.4 Stomata help regulate the rate of transpiration

36.5 Sugars are transported from leaves and other sources to sites of use or storage

36.6 The symplast is highly dynamic

Fig. 36-15

Outside air ψ = −100.0 Mpa

Leaf ψ (air spaces) = −7.0 Mpa

Leaf ψ (cell walls) = −1.0 Mpa

Trunk xylem ψ = −0.8 Mpa

Trunk xylem ψ = −0.6 Mpa

Soil ψ = −0.3 Mpa

Transpiration

Xylemcells

Cohesion andadhesion inthe xylem

Water uptakefrom soil

14,500 psi

Fig. 35-18a

Keyto labels

Dermal

Ground

VascularCuticle Sclerenchyma

fibersStoma

Bundle-sheathcell

Xylem

Phloem

(a) Cutaway drawing of leaf tissues

Guardcells

Vein

Cuticle

Lowerepidermis

Spongymesophyll

Palisademesophyll

Upperepidermis

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

If Psi P = 0.3 MPa and Psi S = -0.45 MPa, the resulting Psi w is

A) +0.75 MPa.

B) -0.75 MPa.

C) -0.15 MPa.

D) +0.15 MPa.

E) -0.42 MPa.

Concept 36.1

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

All of the following involves active transport across membranes except

A) the movement of mineral nutrients from the apoplast to the symplast.

B) the movement of sugar from mesophyll cells into sieve-tube members in maize.

C) the movement of sugar from one sieve-tube member to the next.

D) K+ uptake by guard cells during stomatal opening.

E) the movement of mineral nutrients into cells of the root cortex.

Concept 36.2

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Water potential is generally most negative in which of the following parts of a plant?

A) mesophyll cells of the leaf

B) xylem vessels in leaves

C) xylem vessels in roots

D) cells of the root cortex

E) root hairs

Concept 36.3

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Guard cells do which of the following?

A) protect the endodermis

B) accumulate K+ and close the stomata

C) contain chloroplasts that import K+ directly into the cells

D) guard against mineral loss through the stomata

E) help balance the photosynthesis-transpiration compromise

Concept 36.4

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Arrange the following five events in an order that explains the mass flow of materials in the phloem.

1. Water diffuses into the sieve tubes.2. Leaf cells produce sugar by photosynthesis.3. Solutes are actively transported into sieve tubes.4. Sugar is transported from cell to cell in the leaf.5. Sugar moves down the stem.

A) 2, 1, 4, 3, 5 B) 1, 2, 3, 4, 5 C) 2, 4, 3, 1, 5 D) 4, 2, 1, 3, 5 E) 2, 4, 1, 3, 5

Concept 36.5

Plant Form & FunctionChapter 37: Soil and Plant Nutrition

37.1 Soil is a living, finite resource

37.2 Plants require essential elements to complete their life cycle

37.3 Plant nutrition often involves relationships with other organisms

Plant nutrition. It’s all about soils

Green revolution

Liebig's law of the minimumGrowth determined by most limiting, not by total resources

© M.Slot

Essential elements; elements required for completion of life cycle

Getting there…with a little help from your friends…

Mutualisms -with nitrogen fixing bacteria-with mycorrhizae

Parasitism

Carnivory

(commensalism -epiphytes)

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

All of the following contribute directly to the composition of soil except which one?

a) weathering of source rock

b) remains of dead organisms

c) water and air

d) energy from the sun

e) materials secreted by living organisms

Concept 37.1

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Which of these best describes cation exchange in soils?

a) Cations are exchanged for anions on soil particles.

b) Cation exchange determines the pH of the soil.

c) Mineral cations are displaced from soil particles by H+.

d) Plant root hairs take up cations.

e) Plant root hairs take up anions.

Concept 37.1

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Soil particles are negatively charged; which is most likely to occur during leaching, when water percolates through the soil after a heavy rain?

a) Equal amounts of K+ and HCO3– will be lost into the

groundwater.

b) More Ca2+ and Mg2+ than anions are lost into the groundwater.

c) More Cl– and HCO3– than cations are lost into the

groundwater.

d) More anions become available for root uptake.

e) More cations become available for root uptake.

Concept 37.1

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

For this pair of items, choose the option that best describes their relationship.(A) The amount of essential macronutrients required by plants

(B) The amount of essential micronutrients required by plants

A) Item (A) is greater than item (B).

B) Item (A) is less than item (B).

C) Item (A) is exactly or very approximately equal to item (B).

D) Item (A) may stand in more than one of the above relations to item (B).

Concept 37.2

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

For this pair of items, choose the option that best describes their relationship.

(A) The percent of plant species that form ectomycorrhizae

(B) The percent of plant species that form arbuscular mycorrhizae

A) Item (A) is greater than item (B).

B) Item (A) is less than item (B).

C) Item (A) is exactly or very approximately equal to item (B).

D) Item (A) may stand in more than one of the above relations to item (B).

Concept 37.3

Plant Form & FunctionChapter 38: Angiosperm Reproduction and Biotechnology

38.1Flowers, double fertilization, and fruits are unique features of the angiosperm life cycle

38.2Flowering plants reproduce sexually, asexually or both

38.3Humans modify crops by breeding and genetic engineering

Reproduction. It is (not always) all about sex.

Fig. 38-3a

Development of a malegametophyte (in pollen grain)

Microsporangium(pollen sac)

Microsporocyte (2n)

4 microspores (n)

Each of 4microspores (n)

Malegametophyte

Generative cell (n)

MEIOSIS

Nucleus oftube cell (n)

MITOSIS

stamen carpel

Fig. 38-3b

Ovule

Development of a femalegametophyte (embryo sac)

Megasporangium (2n)

Megasporocyte (2n)

Integuments (2n)

Micropyle

MEIOSIS

Survivingmegaspore (n)

3 antipodal cells (n)

2 polar nuclei (n)

1 egg (n)

2 synergids (n)

Fem

ale gam

etop

hyte

(emb

ryo sa

c)

Ovule

Integuments (2n)

MITOSIS

Fig. 38-5a

Stigma

Pollen tube

2 sperm

Style

Ovary

Ovule

Micropyle Egg

Pollen grain

Polar nuclei

Fig. 38-5b

Ovule

Polar nuclei

Egg

Synergid

2 sperm

From seeds to the next generation

What is a good place for the seedling to grow?

mechanisms of seed dispersal

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

If a single sperm joins with the two polar nuclei to form the cell that will become endosperm but the other sperm fails to fuse with the egg cell, you predict that the resulting fruit will…

a) contain lots of endosperm but no embryo.

b) contain an embryo but no endosperm.

c) never develop.

d) ripen faster.

e) not attract animals.

Concept 38.1

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

A flower has a single carpel, a single ovary, and a single ovule. You predict that the fruit will

a) be small.

b) be fleshy when ripe.

c) have a single seed inside.

d) be dispersed by wind.

e) all of the above

Concept 38.1

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

What is the function of the integument of an ovule?

A) protect against animal predation

B) ensure double fertilization

C) form a seed coat

D) direct development of the endosperm

E) produce hormones that ensure successful pollination

Concept 38.2

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

The banana is losing the battle against two fungal epidemics. Bananas are grown via cloning. One reason they are vulnerable to infection is

a) the offspring remain connected to the parent, so the disease can spread easily.

b) the fungi infect the tools used to cut the connections between parent and offspring.

c) the infection evolved more recently than the banana did.

d) bananas are the world’s most popular fruit, so where bananas can be grown they are everywhere, making it easy for the fungus to be transmitted.

e) bananas are virtually identical genetically, so a disease that can infect one banana probably can also infect other bananas.

Concept 38.2

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Genetically modified organisms are created by combining genes in ways not seen in nature. Therefore, the new organisms are likely to

a) be more competitive and able to spread.

b) have traits that we didn’t expect.

c) be environmentally destructive.

d) spread those new genes through pollen movement.

e) be more tolerant of chemical treatments.

Concept 38.3

Plant Form & FunctionChapter 39: Plant Responses to Internal and External Signals

39.1 Signal transduction pathways link signal reception to response

39.2 Plant hormones help coordinate growth, development and responses to stimuli

39.3 Responses to light are critical for plant success

39.4 Plants respond to a wide variety of stimuli other than light

39.5 Plants respond to attacks by herbivores and pathogens

Hormones. A delicate balance

Important for growth, development and responses to biotic and abiotic factors

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

External stimuli would be received most quickly by a plant cell if the receptors for signal transduction were located in the

A) cell membrane.

B) cytoplasmic matrix.

C) endoplasmic reticulum.

D) nuclear membrane.

E) nucleoplasm.

Concept 39.1

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

We know from the experiments of the past that plants bend toward light because

A) they need sunlight energy for photosynthesis.

B) the sun stimulates stem growth.

C) cell expansion is greater on the dark side of the stem.

D) auxin is inactive on the dark side of the stem.

E) phytochrome stimulates florigen production.

Concept 39.2

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Which of the following does not reduce the level of the Pfr form of phytochrome?

A) exposure to far-red light

B) exposure to red light

C) long dark period

D) destruction of phytochrome

E) synthesis of phosphorylating enzymes

.

Concept 39.3

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

You discover a plant that produces a guard cell hormone under water-deficit conditions. Most likely the hormone is

A) ABA.

B) GA.

C) IAA.

D) 2,4-D.

E) salicylic acid.

Concept 39.4

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

A plant will recognize a pathogenic invader

A) if it has many specific plant disease resistance (R) genes.

B) when the pathogen has an R gene complementary to the plant's antivirulence (Avr) gene.

C) only if the pathogen and the plant have the same R genes.

D) if it has the specific R gene that corresponds to the pathogen molecule encoded by an Avr gene.

E) when the pathogen secretes Avr protein.

Concept 39.5

Animal Form & FunctionChapter 48: Neurons, Synapses, and Signaling

48.1 Neuron organization and structure reflect function in information transfer

48.2 Ion pumps and ion channels maintain the resting potential of a neuron

48.3 Action potentials are the signals conducted by axons

48.4 Neurons communicate with other cells at synapses

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

What happens when?

What happens when?

a) As in g)

b) Na+ channels still closed, K+ channels open

c) Voltage-gated Na+ channels close, voltage-gated K+ channels open

d) Permeability to Na+ at maximum

e) Many voltage-gated Na+ channels open, most gated K+ channels still closed

f) Membrane depolarization: some voltage-gated Na+ channels open

g) Sodium-potassium pump pumps Na+ out & K+ in. Voltage-gated Na+ & K+ channels closed. Some K+ channels open

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

- ions near the channel are attracted to the Na+ ions that have entered

+ ions near the channel are repelled by the Na+ ions that have entered

Na+ ions diffuse away from the channel down their concentration gradient.

+ ions are attracted to the region near the channel due to the lower [Na+ ion]

- ions are repelled from the region near the channel due to the lower [Na+ ion]

Na+ ions diffuse toward the channel down their concentration gradient.

A nervous system can alter activities in its target cells in muscles and glands because A) they are electrically coupled by gap junctions.

B) the target cells have receptor proteins for the signals released by the nervous system.

C) the nervous system releases signals into the blood to control the target cells.

D) the target cells that become disconnected from the nervous system rapidly die.

E) the target cells each have an internal neural network connected to the nervous system.

Concept 48.1

Concept 48.2

The "threshold" potential of a membrane

A) is the point of separation from a living from a dead neuron.

B) is the lowest frequency of action potentials a neuron can produce.

C) is the minimum hyperpolarization needed to prevent the occurrence of action potentials.

D) is the minimum depolarization needed to operate the voltage-gated sodium and potassium channels.

E) is the peak amount of depolarization seen in an action potential.

Concept 48.3

In the sequence of permeability changes for a complete action potential, the first of these events that occurs is

A) the activation of the sodium-potassium "pump."

B) the inhibition of the sodium-potassium "pump."

C) the opening of voltage-gated sodium channels.

D) the closing of voltage-gated potassium channels.

E) the opening of voltage-gated potassium channels.

Concept 48.4

The observation that the acetylcholine released into the junction between a motor neuron and a skeletal muscle binds to a sodium channel and opens it is an example of

A) a voltage-gated sodium channel.

B) a voltage-gated potassium channel.

C) a ligand-gated sodium channel.

D) a second-messenger-gated sodium channel.

E) a chemical that inhibits action potentials.

Animal Form & FunctionChapter 49: Nervous Systems

49.1 Nervous systems consist of circuits of neurons and supporting cells

49.2 The vertebrate brain is regionally specialized

49.3 The cerebral cortex controls voluntary movement and cognitive functions

49.4 Changes in synaptic connections underlie memory and learning

49.5 Nervous system disorders can be explained in molecular terms

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Which system controls smooth and cardiac muscles of the digestive, cardiovascular, and excretory systems?

A) central nervous system

B) peripheral nervous system

C) autonomic nervous system

D) parasympathetic nervous system

E) sympathetic nervous system

Concept 49.1

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Which of the following contains regulatory centers for the respiratory and circulatory systems?

A) cerebrum

B) cerebellum

C) thalamus

D) hypothalamus

E) medulla oblongata

Concept 49.2

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Spinal cord

Pituitarygland

Cerebrum

Cerebellum

Central canal

Diencephalon:

Hypothalamus

Thalamus

Brainstem:MidbrainPonsMedullaoblongata

(c) Adult

The midbrain contains centers for receipt and integration of sensory information

The pons regulates breathing centers in the medulla

The medulla oblongata controls e.g. breathing, cardiovascular activity, swallowing, vomiting, and digestion

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Which of the following describes the functional controls of Wernicke's area?

A) It is active when speech is heard and

comprehended.

B) It is active during the generation of speech.

C) It coordinates the response to olfactory sensation.

D) It is active when you are reading silently.

E) It is found on the left side of the brain.

Concept 49.3

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Short-term memory information processing usually causes changes in the

A) brainstem.

B) medulla.

C) hypothalamus.

D) hippocampus.

E) cranial nerves.

Concept 49.4

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Bipolar disorder differs from schizophrenia in that

A) schizophrenia results in hallucinations.

B) schizophrenia results in both manic and depressive states.

C) schizophrenia results in decreased dopamine.

D) bipolar disorder involves both genes and environment.

E) bipolar disorder increases biogenic amines.

.

Concept 49.5

Animal Form & FunctionChapter 50: Sensory and Motor Mechanisms

50.1 Sensory receptors transduce stimulus energy and transmit signals to the central nervous system

50.2 The mechanoreceptors responsible for hearing and equilibrium detect moving fluid or settling particles

50.3 The senses of taste and smell rely on similar sets of sensory receptors

50.4 Similar mechanisms underlie vision throughout the animal kingdom

50.5 The physical interaction of protein filaments is required for muscle function

50.6 Skeletal systems transform muscle contraction into locomotion

Types of Sensory Receptors

Based on energy transduced, sensory receptors fall into five categories:

1. Mechanoreceptors

2. Chemoreceptors

3. Electromagnetic receptors

4. Thermoreceptors

5. Pain receptors

Fig. 50-3

Connectivetissue

Heat

Strongpressure

Hairmovement

Nerve

Dermis

Epidermis

Hypodermis

Gentletouch

Pain Cold Hair

Fig. 50-8b

Cochlearduct

Vestibularcanal

Bone

Tympaniccanal

Auditorynerve

Organ of Corti

Tectorialmembrane

To auditorynerve

Axons ofsensory neurons

Basilarmembrane

Hair cells

Fig. 50-9

“Hairs” ofhair cell

Neuro-trans-mitter atsynapse

Sensoryneuron

Moreneuro-trans-mitter

(a) No bending of hairs (b) Bending of hairs in one direction (c) Bending of hairs in other direction

Lessneuro-trans-mitter

Action potentials

Mem

bra

ne

po

ten

tial

(mV

)

0

–70

0 1 2 3 4 5 6 7Time (sec)

Sig

nal

Sig

nal

–70

–50 Receptor potential

Mem

bra

ne

po

ten

tial

(mV

)

0

–70

0 1 2 3 4 5 6 7Time (sec)

–70

–50

Mem

bra

ne

po

ten

tial

(mV

)

0

–70

0 1 2 3 4 5 6 7Time (sec)

–70

–50

Sig

nal

“Hairs” ofhair cell

Neuro-trans-mitter atsynapse

Sensoryneuron

Moreneuro-trans-mitter

(a) No bending of hairs (b) Bending of hairs in one direction (c) Bending of hairs in other direction

Lessneuro-trans-mitter

Action potentials

Mem

bra

ne

po

ten

tial

(mV

)

0

–70

0 1 2 3 4 5 6 7Time (sec)

Sig

nal

Sig

nal

–70

–50 Receptor potential

Mem

bra

ne

po

ten

tial

(mV

)

0

–70

0 1 2 3 4 5 6 7Time (sec)

–70

–50

Mem

bra

ne

po

ten

tial

(mV

)

0

–70

0 1 2 3 4 5 6 7Time (sec)

–70

–50

Sig

nal

“Hairs” ofhair cell

Neuro-trans-mitter atsynapse

Sensoryneuron

Moreneuro-trans-mitter

(a) No bending of hairs (b) Bending of hairs in one direction (c) Bending of hairs in other direction

Lessneuro-trans-mitter

Action potentials

Mem

bra

ne

po

ten

tial

(mV

)

0

–70

0 1 2 3 4 5 6 7Time (sec)

Sig

nal

Sig

nal

–70

–50 Receptor potential

Mem

bra

ne

po

ten

tial

(mV

)

0

–70

0 1 2 3 4 5 6 7Time (sec)

–70

–50

Mem

bra

ne

po

ten

tial

(mV

)

0

–70

0 1 2 3 4 5 6 7Time (sec)

–70

–50

Sig

nal

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

What is the correct sequence of events that would lead to a person hearing a sound?1. transmission2. transduction3. integration4. amplification

A) 1, 2, 3, 4

B) 1, 4, 2, 3

C) 2, 4, 1, 3

D) 3, 1, 2, 4

E) 3, 1, 4, 2

Concept 50.1

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

What impact would a nonfunctioning statocyst have on an earthworm? The earthworm would not be able to A) move.

B) sense light.

C) hear.

D) orient with respect to gravity.

E) respond to touch.

Concept 50.2

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

What portion of the brain has neurons that receive action potentials from chemoreceptor cells in the nose? A) gustatory complex

B) anterior hypothalamus

C) olfactory bulb

D) occipital lobe

E) posterior pituitary

Concept 50.3

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Which of the following structures is the last one that sensory information would encounter during visual processing? A) ganglion cells

B) bipolar cells

C) primary visual cortex

D) optic chiasma

E) lateral geniculate nuclei

Concept 50.4

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

When an organism dies, its muscles remain in a contracted state termed "rigor mortis" for a brief period of time. Which of the following most directly contributes to this phenomenon? There is no

A) ATP to move cross-bridges.

B) ATP to break bonds between the thick and thin filaments.

C) calcium to bind to troponin.

D) oxygen supplied to muscle.

E) glycogen remaining in the muscles.

Concept 50.5

Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

A sustained muscle contraction due to a lack of relaxation between successive stimuli is called A) tonus.

B) tetanus.

C) an all-or-none response.

D) fatigue.

E) a spasm.

Concept 50.6