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MOVEMENT and SUPPORT in ANIMALS • MOVEMENT is a displacement from one point to another. • LOCOMOTION is the movement of a WHOLE organism from one place to another. • ONLY ANIMALS carry out locomotion. Reasons why animals move from place to place 1. 2. 3. 4. 5. 6. 7. 8. To obtain food To escape predators To find a mate To distribute offspring To reduce competition To avoid danger To maintain position To avoid waste products Movement in plants Movement in plants is seen when it grows. Growth movements are called TROPISMS. TROPISMS • A tropism is a growth movement of a part of a plant in response to a directional stimulus. • Each response is named according to the nature of the stimulus e.g. a response to light is termed PHOTOTROPISM. Example of Tropic Responses STIMULUS NAME OF RESPONSE EXAMPLE Light Phototropism In almost all plants, shoots will bend towards a directional light source (the direction in which the light is shining) . In roots they bend away ,while leaves position themselves at right angles. See page 143 fig 13.3 Gravity Geotropism In almost all plants, shoots bend away from gravity and roots bend towards it . See page 143 fig 13.3 Water Hydrotropism Almost all plant roots bend towards moisture. Touch Thigmotropism The tendrils of peas twine around supports. The plant Mimosa can close its leaves when touched. Growth in Plants is Controlled by Hormones. • Plant hormones , or plant growth substances as they are often called, are chemical substances produced in plants which will accelerate or modify growth. • Two types of plant growth hormones are 1. Auxins 2. Gibberellins AUXIN • Auxin is a plant hormone which cause growth. • It is made in the tips of shoots and roots which are the growing parts of the plant. • Refer to page 142 and 143 fig 13.2 and 13.3,13.4 and 5 Uses of Plant Hormones • Pesticides are poisonous chemicals which kill pest. • Some plants are classified as weeds and are described as being pest. HERBICIDES are used to kill them. • Synthetic Auxin can be used as a herbicide. When present in larger than normal amounts it will kill a plant. 2,4-D , 2,4,5 – T is an example of a herbicide which kill broad leaf plants. • It causes the plant to over produce auxin stimulating the production of more auxin. • This weed killer causes rapid growth in dicotyledous plants which they cannot sustain , hence they die. Some herbicides are called SYSTEMIC HERBICIDES because they are translocated (transfer of plant material from one area to another )throughout the plant. They move from the leaves to the roots where they interfere with root function killing the root and eventually the whole plant. The Skeleton of Man •The skeleton of man is an ENDOSKELETON. •When the skeleton is located outside the body it is called an EXOSKELETON. Types of Skeletons Exo-skeleton: animals that have shells Endo-skeleton: hard structure inside the animal. Hydrostatic skeleton: Fluid held inside the body No skeleton The human skeleton can be divided into two parts: 1. The axial skeleton 2. The appendicular skeleton The AXIAL SKELETON IS MADE UP OF: 1.THE SKULL 2.VERTEBRAL COLUMN The Skull The Vertebral Column Cervical Vertebrae (7) Thoracic Vertebrae (12) Lumbar Vertberae (5) Sacrum Coccyx LUMBAR VERTEBRA The Thoracic Cage Sternum True Ribs (7) False Ribs (3) Floating Ribs (2) Sacrum & Coccyx INCLUDES ALL OTHER BONES Bones of the Pectoral Girdle Humerus Ulna Radius 8 Carpals 5 Metacarpals 14 Phalanges Pelvis The Lower Limb (Legs) Femur Patella Tibia Fibula 7 Tarsals 5 Metatarsals 14 Phalanges • Support- framework that supports body upright and acts as a frame supporting soft body parts. • Protection- for delicate organs, heart and lungs (rib cage), brain(skull), spinal cord (vertebral column) • Movement- bones act as levers for muscles • Mineral storage- calcium & phosphate • Manufacture of Blood, both Red and White Blood cells – Made in the bone marrow of the pelvis,ribs,sternum and leg bones. MOVEMENT IN MAN •Movement in a limb is brought about by tissues such as muscles, tendon, ligaments and bones. •These all work together to bring about MOVEMENT. • The bones are able to move because of JOINTS in the skeleton. •Joints are the place where two bones meet A Typical Joint How muscles move bones •Bones are attached by LIGAMENTS. •Ligaments are the fibrous, slightly stretchy connective tissues •They hold one bone to another in the body, forming a joint. •They for example preventing your elbow from bending backwards, •Ligaments are composed of strands of collagen fibers. They are slightly stretchy. How muscles move bones • Muscles are attached to bones by tendons. • So what is a tendon? A tendon is a structure that connects muscle to bone, they are nonstretchy. Antagonistic Muscles • Movement is achieved when muscles shorten (contract) and lengthen (relax),by contraction and relaxation of antagonistic muscles. • Antagonistic muscles are PAIRS of muscles; they always work together. • When your biceps contracts it flexes (bends) the elbow joint. The bicep is also called the FLEXOR muscle. • At the same time it also pulls the triceps to make it longer (it relaxes). Antagonistic Muscles •When the triceps contracts is extends (straightens) the elbow joint. The tricep is also called an EXTENSOR MUSCLE •At the same time it pulls the biceps and makes it longer. • The two muscles work together. •Neither muscle can stretch itself, it must be stretched by its antagonist (partner). Types of Joints There are three main types of joints; 1. Fibrous (immoveable), 2. Cartilaginous (partially moveable) and the 3. Synovial (freely moveable) joint. Fibrous (immoveable) • These joints are firmly held together by a thin layer of strong connectice tissue. There is no movement between the bones such as the sutures of the skull and the teeth in their sockets. Cartilaginous (partially moveable/gliding joints) Cartilaginous joints between the thoracic vertebrae. Pivot Joint • Cartilaginous joints :joints in which the bones are attached by cartilage. • Allow for only a little movement, such as in the spine or ribs. • A partially movable joint exist between the atlas and axis at the top of the neck ; this is called a pivot joint. Synovial (freely moveable) joint. • Synovial joints allow for much more movement than cartilaginous joints. • Cavities between bones in synovial joints are filled with synovial fluid. • This fluid helps lubricate (thereby reducing friction) and protects the bones. There are Two Types of Synovial Joints 1. Hinge Joint A hinge joint allows extension and retraction of an appendage. E.g. elbows, knees and finger joints. 2. Bones of hinge joints can carrying large loads HWK • Practice question on pg 151 of textbook. • Correct Answers (except the drawings) will be emailed to you on Saturday..see how many you get right! There are Two Types of Synovial Joints 2. Ball and Socket Joint •A ball and socket joint allows for radial movement in almost any direction. They are found in the hips and shoulders.