Responsible for their other name white muscles for

This preview shows page 12 - 14 out of 79 pages.

responsible for their other name, white muscles) – for rapid, intense actions but the muscle fatigues quickly. o Only sustained for a short time o White muscles are in turkeys This is why they are only capable of short flights. Myoblasts o They are immature muscle cells or fibers. o Rich medium = happy mitosis, beta actin is produced o Invitro o Has a single nucleus o If given a poor medium it indicates to the cells that they should stop dividing, then there will be fibers that have fused together and become multinuclear. Alpha actin is produced. o We may be able to grow meat using myoblasts through invitro Muscle anatomy: Sarcoplasmic reticulum, sarcolemma, sarcoplasm, mitochondria, nuclei … o Sarcoplasm is the equivalent to cytoplasm. o Sarcolemma is the equivalent to the cell membrane. o The reason there is more than one nucleus is that there is repetitive nuclear divisions but no cytokinesis or cell fusion. Nervous system: Consists of the brain, spinal cord, sense organs, and nerves. Neurons are cells in the nervous system that send and receive electrical and chemical signals to and from other neuron throughout the body. o All animals expect sponges have neurons, with the number varying as a function of size and behavioural complexity. Some neurons are covered in a thick layer of connective tissue (myelin sheath) formed by non-neuronal cells (glial cells- named either Schwann cells or oligodendrocytes). o A nerve has hundreds of neurons, with associated glial cells Glial are cells that produce the connective tissue and organize the zones around the neurons, producing myelin for certain nerves. The nerve tract is a bundle of axons. A ganglion is a collection of neuron cell bodies. The myelin sheath is formed by glial cells and acts as an “insulating material”. Vertebrates and simpler chordates have a CNS (central nervous system with a brain and spinal cord) and a PNS (peripheral nervous system). You can see the similarity to the segmentation of invertebrates. Specialization of function o Afferent neurons carry signals toward the brain o Efferent neurons away from the brain
Sensory Neuron: Get information from the outside world and send that information to the CNS. Consist of long dendrites Motor Neurons: Sends signals away from sensory neurons for a response. Act on signal sent from the sensory neuron. Interneuron: Make interconnections with other neurons. Highly branched. Make connections (1000-10000 connections) Neural Circuit: Consists of chemical, pressure, heat, and electric shock reactions. o Electric shock goes from the dendrites of the sensory neurons to the motor neurons Voltage Sensitive Ion Channels: Not pumps; do not require ATP directly. They sit in membranes. Sodium channel o Outside of cell has higher concentration of sodium than inside of the cells o This is set up by the sodium potassium ATPase o The outside is more positive relative to the inside of the membrane o Going from high to low concentration (with the gradient). o

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture