Aquatic Plant Support Systems

Test your knowledge on the different types of aquatic plants and the unique adaptations, like air sacs, that help them float and get sunlight.

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1. What is the primary mechanism that allows aquatic plants with soft stems to stay upright in water?

A) The turgidity of their cells B) A strong internal skeleton C) The buoyancy of the water D) A rigid external cuticle

Explanation: The text states, 'aquatic plants can stay upright in water because their weights are supported by the buoyancy of water.'

2. Which feature is common in aquatic plants like Vallisneria, water hyacinth, and water lily to aid in floating?

A) Thick, woody stems B) Deep, anchoring roots C) The presence of numerous air sacs or spaces D) Very large, broad leaves

Explanation: The text mentions 'numerous air sacs' for submerged plants, 'numerous air spaces' in the petioles of free-floating plants, and 'aerenchyma tissues (spongy and air spaces)' for submerged floating plants, all serving to help the plant float.

3. A plant is observed to float freely on the water's surface, with swollen and spongy petioles. Which type of plant is it?

A) Submerged plant B) Free floating plant C) Submerged floating plant D) Trailing floating plant

Explanation: According to the text, free-floating plants, like the water hyacinth, 'float freely on the water surface' and have 'petioles [that] are swollen and spongy, consisting of numerous air spaces.'

4. Which of the following plants is described as being anchored to the bottom by roots while its leaves and flowers float on the surface?

A) Water hyacinth B) Vallisneria C) Buffalo spinach D) Water lily

Explanation: The text identifies the water lily (Kya) as a 'submerged floating plant' that 'anchor[s] to the bottom of the pond by roots but their leaves and flowers float on the water surface.'

5. What is the key characteristic of trailing floating plants, such as buffalo spinach?

A) They are rooted at the bottom with all leaves underwater. B) They float freely without any roots. C) They have long, horizontal, and hollow stems called stolons. D) Their leaves are tiny to avoid disruption by water flow.

Explanation: The section on trailing floating plants explicitly states, 'These plants have long and horizontal stems (stolon). These stems are hollow and can float easily.'

6. In submerged plants like Vallisneria, what is the main purpose of having air sacs?

A) To store food reserves B) To keep the plant floating close to the surface for sunlight C) To deter predators D) To absorb more water

Explanation: The text about submerged plants says that 'Numerous air sacs inside the leaves and stems keep the plant floating close to the surface to obtain maximum sunlight.'

7. How do plants primarily gain support on land, as contrasted with aquatic plants in water?

A) Through the buoyancy of the air B) By using skeletons similar to animals C) Through the turgidity of cells and strongly constructed conducting tissue D) By having numerous air sacs in their stems

Explanation: The text states that plants on land 'use their turgidity of cells within packing tissue and the strongly constructed conducting tissue for support,' which is different from the buoyancy that supports aquatic plants.

8. According to the text, what is the primary cause of physiological support in terrestrial plants?

The lignification of cell walls. The development of woody tissues. The turgor pressure created by osmosis. The formation of specialized climbing roots.

Explanation: The section '(a) The physiological support' states that water enters the cell's vacuole by osmosis, creating an internal pressure called turgor pressure, which pushes against the cell wall and provides support.

9. Which of the following best describes a key difference between physiological and structural support in plants?

Physiological support is permanent, while structural support is temporary. Physiological support is found only in woody plants, while structural support is in non-woody plants. Physiological support depends on water availability, while structural support is permanent and based on specialized tissues. Physiological support involves xylem and phloem, while structural support involves parenchyma.

Explanation: The text explains that physiological support is temporary and depends on water, whereas structural support is a permanent system involving specialized tissues like sclerenchyma and xylem.

10. Based on the description, what is a characteristic feature of 'Trailing floating plants' like the Buffalo spinach in Figure 3.4?

They have erect, sword-shaped leaves. They have hollow, horizontal stems (stolons) that help them float. They depend on thick, woody stems for support. They have climbing roots to attach to surfaces.

Explanation: The text under section '(c) Trailing floating plants' explicitly states that these plants have long, horizontal, and hollow stems (stolons) that allow them to float easily.

11. What happens to a plant when it lacks turgor pressure, as illustrated by the wilted plant in Figure 3.6?

The cells become turgid and the plant stands erect. The plant loses support and becomes flaccid. The plant develops stronger structural tissues. The plant's climbing roots grow stronger.

Explanation: Figure 3.6 visually contrasts a plant with turgor pressure (erect) and one without (wilted). The text explains that without turgor pressure, the cell is no longer turgid, leading to a loss of support for the plant.

12. Support in woody plants is provided by specialized tissues. Which of the following is NOT listed as a supportive tissue for woody plants?

Sclerenchyma tissues Xylem Parenchyma Tracheids

Explanation: The section 'Support in woody plants' mentions sclerenchyma tissues, xylem, vessels, and tracheids. Parenchyma is mentioned under 'Support in non-woody plants' as a tissue whose turgidity provides support.

13. How do non-woody plants, such as climbers, primarily achieve support?

Through the development of a thick, woody stem. Through the lignification of their cell walls. Through the turgidity of cells like parenchyma and collenchyma. Through the formation of primary and secondary xylem.

Explanation: The text under 'Support in non-woody plants' states that their support 'depends on the turgidity of their cells such as parenchyma, collenchyma and other supportive tissues'.

14. Which plant type is characterized by tufts of basal leaves rising from spreading rhizomes, as seen with the sweet flag in Figure 3.5?

Trailing floating plants Emergent plants Woody plants Climbers

Explanation: The description for '(3) Emergent plants' says they consist of 'tufts of basal leaves which rise from the spreading rhizomes,' which matches the description and the example of the sweet flag.

15. According to the text, what is the primary difference between thorns and prickles?

Thorns are sharp, while prickles are blunt. Thorns are modified branches, while prickles are outgrowths of the epidermis. Thorns are found on roses, and prickles are found on bougainvillea. Thorns help with support, while prickles are for defense.

Explanation: The textbook explicitly states that thorns are 'modified branches that cannot be easily removed,' whereas prickles are 'an outgrowth of the epidermis' that 'can be easily removed from the stem.'

16. Which type of plant support structure is described as thick roots growing from the stem above the ground to hold a tree firmly, with durian and casuarina given as examples?

Prop roots Tendrils Buttress roots Clasping roots

Explanation: The text defines buttress roots as 'The thick support roots grow from the stem above the ground. These roots hold the tree firmly to the ground,' and lists durian and casuarina as examples.

17. Which of the following animal groups is described as having a hydrostatic skeleton?

Vertebrates like fish and frogs Arthropods like insects and crustaceans Soft-bodied invertebrates like earthworms and jellyfish Echinoderms like sea urchins

Explanation: The section on hydrostatic skeletons states they are 'found primarily in soft-bodied terrestrial invertebrates such as earthworms and slugs and soft-bodied aquatic invertebrates such as jellyfish and squids.'

18. What is a key characteristic of an exoskeleton, as mentioned in the text?

It is an internal frame made of bone. It is composed of a rigid, hard case made of chitin that must be molted for the animal to grow. It uses fluid-filled cavities and hydrostatic pressure for support. It is made of calcium carbonate ossicles found in sea urchins.

Explanation: The text describes an exoskeleton as a 'rigid, hard case' made of 'chitin' and notes that 'in order to grow, the animal must periodically molt, shedding the exoskeleton.'

19. The textbook distinguishes between the endoskeletons of vertebrates and echinoderms. What are their respective primary chemical compositions?

Chitin and calcium carbonate Calcium phosphate and calcium carbonate Calcium carbonate and calcium phosphate Calcium phosphate and chitin

Explanation: The text states that vertebrate bones are 'based mainly on calcium phosphate' and that echinoderms have endoskeletons 'of ossicles made of calcium carbonate.'

20. A plant is observed with curly, string-like structures that are coiling around a fence to help it climb. Based on the provided text, what are these structures called?

Prop roots Tendrils Thorns Clasping roots

Explanation: Tendrils are defined as 'Curly string-like structures modified from the stems and leaves [that] curl and twine around the parts of other plants or objects to help the plant to climb.'

21. Based on the information provided, what type of skeleton would a crab, which is a crustacean, possess?

Hydrostatic skeleton Exoskeleton Endoskeleton A cartilaginous skeleton

Explanation: The text clearly states that 'Arthropods such as crustaceans and insects have exoskeletons.' Since a crab is a crustacean, it has an exoskeleton.

22. According to the text, the human skeleton is primarily categorized into which two parts?

A) Cranial and Postcranial skeleton B) Axial and Appendicular skeleton C) Superior and Inferior skeleton D) Endoskeleton and Exoskeleton

Explanation: The first paragraph of section 3.1.4 explicitly states that the human skeleton can be categorized as part of either the 'axial or appendicular skeleton'.

23. Which of the following is NOT a function of the human endoskeletal system as described in the text?

A) Protecting vital internal organs B) Producing hormones for regulation C) Serving as a storage reservoir for ions like calcium D) Producing blood cells in the red bone marrow

Explanation: The text lists four functions: support and protection, providing sites for muscle attachment, ion storage, and blood cell production. Hormone production is not mentioned as a function of the skeletal system.

24. Which of these bone groups belongs to the axial skeleton?

A) Humerus, ulna, and radius B) Femur, patella, and tibia C) Skull, ribs, and sternum D) Clavicle, scapula, and pelvis

Explanation: The section on the Axial skeleton states that it includes the skull, the spine, the 12 pairs of ribs, and the breast-bone (sternum). The other options list bones of the appendicular skeleton.

25. Based on the provided diagram, which labeled bone is part of the appendicular skeleton?

A) Spine (vertebrae) B) Skull C) Sternum (breast-bone) D) Femur

Explanation: The appendicular skeleton consists of the limbs and girdles. The femur is the thigh bone, which is part of the leg (a limb). The skull, spine, and sternum are all parts of the axial skeleton.

26. What is the primary role of the girdles, such as the pelvis and the combination of the clavicle and scapula?

A) To protect the spinal cord B) To produce red blood cells C) To connect the limbs to the axial skeleton D) To form the rib cage

Explanation: The text under 'Appendicular skeleton' states that it 'includes two sets of bones, called girdles that connect limbs to the axial skeleton of the body'.

27. The text states that the bones of the axial skeleton, such as the vertebrae, cover most of the body's vital organs. What specific vital structure do the vertebrae surround and protect?

A) The heart and lungs B) The brain C) The spinal cord D) The digestive tract

Explanation: In the 'Axial skeleton' section, the text says, 'Vertebrae are serially arranged bones of the spine that surround the spinal cord'.

28. In the diagram, the humerus, radius, and ulna form the arm. These bones are part of which division of the skeleton?

A) Axial skeleton B) Appendicular skeleton C) Cranial skeleton D) Thoracic skeleton

Explanation: The appendicular skeleton is defined as the part that includes the bones in the limbs, such as arms and legs. The humerus, radius, and ulna are the bones of the arm.

29. According to the text, what is the primary function of red bone marrow?

To store fat To produce blood cells To provide a hard matrix for the bone To transmit nerve signals

Explanation: The text states that the marrow cavity may contain 'red marrow where blood cells are produced.'

30. What is the role of the Haversian canals in bone tissue?

They produce new bone cells. They connect bones to other bones. They store calcium and phosphate. They contain blood vessels and nerves for oxygen supply and control.

Explanation: The text describes that 'Haversian canals running through the matrix of the bone consist of blood vessels and nerves for oxygen supply and control of the bone cells.'

31. What type of tissue is found at the ends of bones to prevent wear and allow for smooth movement?

Ligament Tendon Cartilage Fibrous tissue

Explanation: The text explains that 'the ends of the bones are protected from wear by cartilage' and that cartilage 'allows for smooth movements.'

32. Which type of joint allows for the greatest degree of movement between bones?

Fibrous joints Cartilaginous joints Synovial joints Fused joints

Explanation: The passage states, 'Synovial joints allow great degree of movement between bones,' while fibrous joints act as glue and cartilaginous joints allow only partial movement.

33. Based on Table 3.1, which of the following is an example of a hinge joint?

Shoulder joint Hip joint Elbow joint Skull and atlas

Explanation: Table 3.1 clearly lists the 'Elbow joint' and 'knee joint' as examples of a hinge joint, which allows for flexion and extension.

34. What type of movement is characteristic of a pivot joint, such as the one between the skull and atlas?

Flexion and extension Rotation Circumduction Adduction and abduction

Explanation: In Table 3.1, the 'Movements' column for the 'Pivot joint' is listed as 'Rotation'.

35. Which type of synovial joint allows for flexion, extension, adduction, abduction, and circumduction?

Hinge joint Saddle joint Pivot joint Ball and socket joint

Explanation: Table 3.1 specifies that the 'Ball and socket joint' is capable of 'Flexion, extension, adduction, abduction, circumduction.'

36. According to Table 3.1, what type of joint is found between the carpal bones of the wrist?

Saddle joint Hinge joint Pivot joint Gliding joint

Explanation: The table lists 'between carpal bones (shown) of wrist' as an example of a Gliding joint.

37. Which of the following movements is associated with a Saddle joint as described in the provided text?

Rotation Gliding Circumduction Only flexion

Explanation: The 'Movements' column for the Saddle joint lists flexion, extension, adduction, and circumduction.

38. Based on the text, what is the term for a plant's growth movement towards or away from a directional stimulus like light?

Nastic movement Tropic movement Photosynthesis Transpiration

Explanation: The section 'Tropic Movements' defines this as 'The movement of a plant in the direction of stimulus'.

39. How does the shoot system of a plant exhibit phototropism?

It shows negative phototropism (bends away from light). It shows positive phototropism (bends towards light). It is not sensitive to light. It grows straight regardless of light direction.

Explanation: The text under 'Phototropism' states that 'The shoot system of a plant shows positively phototropic' behavior.

40. Which nutrient is mentioned as playing a 'critical role in muscle and cartilage repair'?

Vitamin C Calcium Proteins Iron

Explanation: In the section '(c) Eat healthy food', the text explicitly says, 'Proteins play a critical role in muscle and cartilage repair'.

41. What is described as a 'non-growth dependent' plant movement that is 'not dependent on the direction of stimulus'?

Phototropism Geotropism Tropic movements Nastic movements

Explanation: The introductory text on plant movement distinguishes between tropic movements and 'Non-growth dependent movements called the nastic movements (not dependent on the direction of stimulus)'.

42. According to the section on maintaining a healthy musculoskeletal system, what is a direct benefit of reducing body weight through exercise?

Increased bone brittleness Reduced joint pain and improved joint health Increased risk of osteoarthritis Damaged cartilage and ligaments

Explanation: The text under point (d) states, 'Reducing body weight by exercising regularly reduces joint pain, improve joint health and keeps muscle strong'.

43. According to the text and Figure 3.19, which statement correctly describes geotropism in plants?

The shoot is positively geotropic, and the root is negatively geotropic. Both the shoot and the root are positively geotropic. The shoot is negatively geotropic, and the root is positively geotropic. Both the shoot and the root are unresponsive to gravity.

Explanation: The text under section (b) Geotropism explicitly states: 'In geotropism, the shoot is negatively geotropic and the root is positively geotropic'. This means the shoot grows away from gravity, and the root grows towards it.

44. The movement of a plant tendril coiling around a support structure like a bamboo stick, as shown in Figure 3.22, is an example of what?

Hydrotropism Thigmotropism Chemotropism Nastic movement

Explanation: Section (e) Thigmotropism defines this as 'The directional movement in plants in response to touch' and provides the example of plant tendrils climbing around any support they touch.

45. What is the key difference between tropisms (like geotropism, hydrotropism) and nastic movements?

Tropisms are slow, while nastic movements are fast. Tropisms are directional movements in response to a stimulus, while nastic movements are non-directional. Tropisms only occur in response to light and gravity, while nastic movements occur in response to touch. Tropisms are reversible, while nastic movements are permanent.

Explanation: Section 3.2.2 on Nastic Movements clearly states that they 'are not directional movements. They are not dependent on the direction of the stimulus,' which distinguishes them from tropisms.

46. Based on the description of Chemotropism (Figure 3.21), what stimulates the growth of the pollen tube towards the ovule?

The force of gravity A light source from the ovule The secretion of a sugary chemical Physical contact with the polar nuclei

Explanation: The text for section (d) Chemotropism gives a specific example: '...growth of pollen tube towards ovule during fertilization due to secretion of a sugary chemical in the ovary.'

47. The folding of the leaves of a Mimosa plant when touched (Figure 3.24) is categorized as what type of plant movement?

Thermotropism Thigmotropism Nastic movement Geotropism

Explanation: The text under Nastic Movements uses the Mimosa ('touch me not') plant as a primary example, noting that its leaves 'fold up immediately when touched' as a non-directional response.

48. What type of tropism is being demonstrated by the pea seedling's root in Figure 3.20?

Phototropism Geotropism Hydrotropism Thermotropism

Explanation: Figure 3.20 and the accompanying text explain hydrotropism, 'The movement of the plant towards the water.' The image shows the root exhibiting 'hydrotropic curvature' towards the water in the porous pot.

49. The response of plant parts to changes in temperature, such as the leaves shown in Figure 3.23, is known as:

Thermotropism Chemotropism Nastic movement Hydrotropism

Explanation: Section (f) defines Thermotropism as 'the movement of plant or their parts in response to changes in the external stimulus of temperature,' which is illustrated in Figure 3.23.

50. According to the text, what type of skeleton does an earthworm have, which consists of a fluid-filled central body cavity?

A) Exoskeleton B) Endoskeleton C) Hydrostatic skeleton D) Chitinous skeleton

Explanation: The text states that in earthworms, 'Muscles act on the fluid in the body's central space which represents the hydrostatic skeleton.'

51. In earthworm locomotion, what is the effect of the circular muscles contracting while the longitudinal muscles relax in a segment?

A) The segment becomes shorter and wider, anchoring to the ground. B) The segment extends forward, becoming longer and thinner. C) The setae retract into the body wall. D) The segment bends sharply to the left or right.

Explanation: As described in steps 1 and 2 of earthworm locomotion, when circular muscles contract and longitudinal muscles relax, the front end of the body extends forward. The diagram (Figure 3.26) also illustrates that a segment with contracted circular muscles is elongated.

52. What is the primary function of the bristle-like structures called setae in an earthworm?

A) To sense vibrations in the soil. B) To aid in gas exchange. C) To anchor the body to the ground and prevent slipping. D) To help digest organic matter.

Explanation: The text explains that setae 'anchor the ground' and 'prevent slipping backward' during the wave of muscle contractions that produces movement.

53. For a grasshopper to prepare for a jump, its hind leg is folded. Which muscle action causes this?

A) The extensor muscle contracts. B) The flexor muscle contracts. C) Both the flexor and extensor muscles contract. D) Both the flexor and extensor muscles relax.

Explanation: The text on jumping states: 'When the flexor muscle contracts, the lower leg (tibia) is pulled towards the body. The hind leg is folded in a Z shape and ready for a jump.' This is also shown in Figure 3.27a.

54. Which pair of muscles in a grasshopper works antagonistically to produce jumping movements?

A) Elevator and depressor muscles B) Circular and longitudinal muscles C) Flexor and extensor muscles D) Tergum and tibia muscles

Explanation: The text explicitly refers to 'The flexor and extensor (antagonistic) muscles' being responsible for bending and straightening the joint in a grasshopper's leg for jumping.

55. During the flight of a grasshopper, which muscles are responsible for raising the wings?

A) Depressor muscles B) Flexor muscles C) Elevator muscles (extensor) D) Leg muscles

Explanation: The section on flight mentions that movement of the wings is achieved by the 'alternate contraction of extensor muscles (elevators) and flexor muscles (depressors)'. The elevators are responsible for raising the wings, as shown in Figure 3.27b.

56. What action propels a grasshopper forward and up into a jump?

A) Rapid contraction of the flexor muscle. B) Slow relaxation of the extensor muscle. C) Rapid contraction of the extensor muscle. D) Simultaneous contraction of both flexor and depressor muscles.

Explanation: The text describes the jump: 'When the extensor muscle contracts, the leg jerks backwards, propelling the grasshopper forward and up.'

57. According to the text and Figure 3.27, what muscle action allows a grasshopper to jump?

The flexor muscle contracts and the extensor muscle relaxes. The extensor muscle contracts and the flexor muscle relaxes. Both the extensor and flexor muscles contract simultaneously. The depressor muscle contracts to extend the tibia.

Explanation: Figure 3.27 (a) shows that for a grasshopper to jump, the extensor muscle contracts, which causes the tibia to extend, while the antagonistic flexor muscle relaxes.

58. What is the primary function of the pectoral fins on a fish?

To propel the fish forward To balance the body and prevent rolling To steer the fish To reduce friction in the water

Explanation: The text under 'Locomotion in fish' explicitly states, 'Pectoral fins are used to steer the fish.'

59. Which muscle is responsible for the powerful downstroke of a bird's wings, which provides lift during flight?

Supracoracoideus Pectoral Sternum Humerus

Explanation: The text on 'Locomotion in bird' states that 'the pectoral muscles contract to cause downstroke of the humerus bone of the wings... providing lift.'

60. When a frog extends its hind legs to leap or swim, which muscles contract?

Flexor muscles Pelvic girdle muscles Spine muscles Extensor muscles

Explanation: As described in the section on frog locomotion and shown in Figure 3.29 (b), the strong extensor muscles of the thigh contract to extend the limb for leaping or swimming.

61. The text describes how muscles in different animals often work in 'antagonistic pairs'. What does this mean?

Two muscles contract at the same time to create a powerful movement. One muscle contracts while its opposing muscle relaxes to cause movement. Muscles that are located on opposite sides of the body, like left and right. Muscles that have the same function but different attachment points.

Explanation: The introductory paragraph under section 3.3.2 defines this principle: 'As one muscle contracts, the other relaxes causing movement or locomotion at different types of bony joints.'

62. What is the primary role of the myotomes in fish?

They form the streamlined body shape. They control the pectoral and pelvic fins for balance. They are antagonistic muscles on the sides of the body that contract and relax to propel the fish. They help the fish sense pressure changes in the water.

Explanation: The text states that a fish moves forward 'as a result of the contraction and relaxation of (antagonistic) muscles called myotomes on either side of the body'.

63. To which bone are the major flight muscles of a bird, the pectoral and supracoracoideus, attached?

Humerus Spine Ribs Breast bone (sternum)

Explanation: In the 'Locomotion in bird' section, the text clearly states, 'Both muscles are attached to the breast bone (sternum).'

64. According to Figure 3.31(a), what happens to the biceps and triceps muscles during the extension of the arm?

A) Biceps contracts, triceps relaxes B) Biceps relaxes, triceps contracts C) Both muscles contract D) Both muscles relax

Explanation: The diagram and text both indicate that for arm extension, the triceps brachii contracts to pull the forearm away from the upper arm, while the biceps brachii relaxes.

65. The text describes a working muscle as an 'agonist' and a resting muscle as an 'antagonist'. During the flexion of the leg at the knee, which muscle is the agonist?

A) Quadriceps B) Biceps brachii C) Triceps brachii D) Hamstring

Explanation: As stated in the text and shown in Figure 3.31(b), flexion of the leg at the knee is caused by the contraction of the hamstring (flexor), making it the agonist in this movement.

66. What is the primary function of the quadriceps muscle as illustrated in Figure 3.31(b)?

A) To flex the leg B) To extend the leg C) To rotate the thigh D) To stabilize the hip joint

Explanation: The diagram labels the quadriceps as 'extensors' and shows them contracting to straighten or extend the leg.

67. What general term does the textbook use to describe pairs of muscles, like the biceps and triceps, that work in opposition to each other for movement?

A) Synergistic pairs B) Coordinated pairs C) Antagonistic pairs D) Parallel pairs

Explanation: The text explicitly states, 'Most of these muscles function in “antagonistic pairs” for locomotion and movement in humans.'

68. What movement is produced when the biceps brachii contracts and the triceps brachii relaxes?

A) Extension of the arm B) Flexion of the leg C) Extension of the leg D) Flexion of the arm

Explanation: The text describes that the 'Contraction of biceps brachii flexes or pulls the forearm towards the upper arm.' This movement is called flexion.

69. Which of the following pairs of muscles are presented as an example of an antagonistic pair in the thigh?

A) Biceps and triceps B) Hamstring and quadriceps C) Agonist and antagonist D) Flexors and extensors

Explanation: The text provides a second example of an antagonistic pair: '...the hamstring and quadriceps muscles in the thigh of the legs.'

70. Based on Figure 3.31(b), what is the state of the hamstring and quadriceps muscles during the extension of the leg?

A) Hamstring contracts, quadriceps relaxes B) Hamstring relaxes, quadriceps relaxes C) Hamstring contracts, quadriceps contracts D) Hamstring relaxes, quadriceps contracts

Explanation: The diagram for leg extension clearly shows the extensors (quadriceps) contracting and the flexors (hamstring) relaxing to straighten the leg.