The elements for life found in living cells.

SULFER: protein folding

PHOSPHORUS: Important for RNA/DNA-build membrane-ATP.

OXYGEN: For cellular respiration for making energy.

NITROGEN: For protien - amino acids.

CARBON: Universal backbone of all living things - long chains of covelant bonds.

HYDROGEN: H-bonds ,protien folding, and H2O.

Glucose + Oxygen = Carbon dioxide + Water + Usable energy

C₆H₁₂O₆ + 6 O₂ →  6 H₂O + 6 CO₂ + Energy  ATP + heat

Passive transport - no energy

Diffusion - movment from high concentration to low

Osmosis- diffusion of water

Surface area to volume ratio requires that cells be small.
¨As cells get larger in volume, relative surface area actually decreases.
¨Limits how large actively metabolizing cells can become
¨Cells needing greater surface area use modifications such as folding, microvilli.

The flow of information from the DNA in the nucleus of the cell, into messenger RNA via transcription, and thence into proteins. Transcription take place inside the nucleus - Translation takes place outside the nucleus.

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Connective tissue

Connective tissues are fibrous tissues. They are made up of cells separated by non-living material, which is called extracellular matrix. Connective tissue gives shape to organs and holds them in place. Both blood and bone are examples of connective tissue. As the name. It supports and binds other tissues. Unlike epithelial tissue, connective tissue typically has cells scattered throughout an extracellular matrix2.

Muscle tissue

Muscle cells form the active contractile tissue of the body known as muscle tissue or muscular tissue. Muscle tissue functions to produce force and cause motion, either locomotion or movement within internal organs. Muscle tissue is separated into three distinct categories: visceral or smooth muscle, which is found in the inner linings of organs; skeletal muscle, in which is found attached to bone providing for gross movement; and cardiac muscle which is found in the heart, allowing it to contract and pump blood throughout an organism.

Nervous tissue

Cells comprising the central nervous system and peripheral nervous system are classified as neural tissue. In the central nervous system, neural tissue forms the brain and spinal cord and, in the peripheral nervous system forms the cranial nerves and spinal nerves, inclusive of the motor neurons. Nervous tissue functions to transmit messages in form of impulse.

Epithelial tissue

The epithelial tissues are formed by cells that cover the organ surfaces such as the surface of the skin, the airways, the reproductive tract, and the inner lining of the digestive tract. The cells comprising an epithelial layer are linked via semi-permeable, tight junctions; hence, this tissue provides a barrier between the external environment and the organ it covers. In addition to this protective function, epithelial tissue may also be specialized to function in secretion and absorption. Epithelial tissue helps to protect organisms from microorganisms, injury, and fluid loss. Functions:

• the cell of the body surface form the outer layer of skin.
• inside the body,epithelial cells forms lining of mouth & alimentary canal & protect these organ.
• epithelial tissues help in absorption of water & nutrient.
• epithelial tissues help in elimination of waste product.

The different types of epithelial tissues are as follows:

• Squamous epithelium,
• Cuboidal epithelium,
• Columnar epithelium,
• Glandular epithelium,
• Ciliated epithelium

Although the keratinocytes have the absolute majority, other cells - melanocytes, Langerhans cells and Merkel cells - co-exist with them in the epidermis. Each of these types have specific, and no less vital, functions

Highly organize osteons into tight rings around blood vessels for support

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The spinal cord and the brain make up the CNS. Its main job is to get the information from the body and send out instructions.

 The peripheral nervous system (PNS) is made up of all of the nerves and the wiring. This system sends the messages from the brain to the rest of the body. Allactivity outside of th CNS

Myelin forms an insulating wrapping around large nerve axons. In the peripheral nervous system myelin is formed by Schwann cells (a type of supporting cell) that wrap repeatedly around the axon. In the central nervous system myelin is formed by repeated wrappings of processes of oligodendrocytes (a different type of supporting cell). The process of each cell forms part of the myelin sheath.The space between the myelin from individual Schwann cells or oligodendrocyte processes is a bare region of the axon called the node of Ranvier. Nerve conduction is faster in myelinated fibers because it jumps from one node of Ranvier to the next.

White matter is one of the two components of the central nervous system and consists mostly of glial cells and myelinated axons (Mylin)

Grey matter which is composed of neurons (cell bodies)

There are 31 pairs of spinal nerves in the human body.Ascending tracts within the spinal cord carry information from the body, upwards to the brain, such as touch, skin temperature, pain and joint position.
Descending tracts within the spinal cord carry information from the brain downwards to initiate movement and control body functions.
 

contain and distribute CSF.which provides the following functions:        

Absorbs physical shocks to the brain

Distributes nutritive materials to and removes wastes from nervous tissue

1.Due to Na+/K pump resting membrane potential is at -70 mv.

2.At threshold -55 mv= Na channel opens into cell.

3.Depolarization rapid influx of Na.

4. At +30 mv Na chanels lock and K channels open.

5. Repolarization rapid efflux of K out of cell.

6. Hyperpolarization K chanels close Na channel unlocks.

7.Na/K pump resets .

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Once initiated the action potential travels uni directionaly to the end of the axon.backward flow is prevented by the refractory period of the preceding membrane. Myelin increases the speed of the action potential

As an impulse reaches an end of a neuron, called an axon terminal, the impulse opens ion pores in that axon terminal which allows Calcium ions to enter, which cause the movement of small membrane bounded packets of neurotransmitter chemicals, called vesicles (like tiny water balloons), to move to the cell membrane, where the vesicles fuse into the cell membrane, thus releasing the contents, the neurotransmitters, into the small space (the synaptic cleft) between the axon terminal and the dendrite of the post-synaptic neuron (the neuron the impulse is traveling to).

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In a classic synapse, calcium's main role is to trigger the release of chemicals (called neurotransmitters) from the presynaptic neuron. How calcium does this is well established and is achieved through voltage-gated calcium channels located on the membrane of the presynaptic terminal. These channels open in response to membrane depolarization, the type of signal carried by an action potential.
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1. Re-uptake of neurotransmitters

2.Enzymatic clear-age of neurotransmitters

3.neurotransmitters diffuse away

Divergence is the spread of information from one neuron to several neurons .

Convergence several neurons synapse on the same post synaptic neuron

A two motor neuron pathway  allows for the brain to have an opposing effect on the same organ.

Preganglionic and postganglionic neurotransmittersare important for the activity of the ANS

1. Projection:understanding which receptors are stimulated.

2. Intensity: degree of stimulation.

3.Contrast: comparison of current stimulus to previous stimuli .

4. Adaptation: becoming unaware of continuing pain.

5. After image: sensation remain in the consciousness even after thought ha stopped.

1. Olfactory - sensory nerves for smell. These nerves arise in the olfactory receptors of the nasal epithelium and pass through holes in the cribriform plate to reach the olfactory bulb on the ventral brain surface. The olfactory tracts lead from these bulbs back to the thalamus and then to the frontal lobe for smell perception.
2. Optic - sensory only for vision. These fibers arise from the retina at the optic disk and travel to the optic chiasma where half of them crossover. From there the optic tracts take impulses to the thalamus which relays them to the visual cortex in the occipital lobe and visual reflex center in the midbrain. 
3. Oculomotor * - motor to the extrinsic and intrinsic eye muscles (except superior oblique and lateral rectus). Its parasympathetic fibers control muscles of the iris (for constricting the pupil) and the ciliary disk, for accommodation of the lens for near vision.
4.Trochlear - controls the superior oblique muscle of the eye. Called the trochlear because the tendon of this muscle passes through a pulley-shaped process called a trochlea.

5. Trigeminal - Sometimes called the 'great sensory nerve of the face' this is the largest of the cranial nerves. It has three branches, the ophthalmic, maxillary, and mandibular. From these it receives sensations of a conscious nature, and controls the muscles for chewing.  
6. Abducens - Its name says what this nerve effects - abduction of the eye. It controls the lateral rectus muscle.  
7. Facial *- The chief motor nerve of the face, to muscles of facial expression, and parasympathetic to lacrimal and salivary glands. Sensory for taste from the anterior two-thirds of tongue. 
8. Acoustic or Auditory or Statoacoustic or Vestibulocochlear - this is the nerve bringing stimuli from the inner ear for perception of hearing and balance.

9. Glossopharyngeal * - Motor to the muscles for swallowing and parasympathetic to the parotid gland. Sensory from taste buds on the posterior tongue and other areas, as well as other conscious sensations. It is also important in the sensory pathways for control of blood pressure and respiration. 
10. Vagus * - The parasympathetic nerve to the viscera. Its fibers send stimuli to the heart, stomach, intestines, bronchi, and virtually every other parasympathetic effector between the head and the pelvis. The vagus also provides sensory input for cardiac and respiration. But the muscles of respiration are voluntary and respiration itself is NOT an autonomic function. 
11. Spinal Accessory - Runs together with spinal nerves to the sternocleidomastoid and trapezius muscles.  
12. Hypoglossal - Motor to the muscles of swallowing.

vagus 

Rods are responsible for vision at low light levels

 Cones are active at higher light levels are capable of color vision and are responsible for high spatial acuity. The central fovea is populated exclusively by cones. There are 3 types of cones which we will refer to as the short-wavelength sensitive cones, the middle-wavelength sensitive cones and the long-wavelength sensitive cones or S-cone, M-cones, and L-cones for short

Through vibration.

-> ear drum  ->  bone  ->  cochlia  ->  fluid in cochlia duct  ->  hair cells  ->  action potential  ->  cranial nerve 8 (Auditory)

1) Smooth muscle- controlled by the autonomic nervous system; may either be generally inactive and then respond to neural stimulation or hormones or may be rhythmic

2) Cardiac muscle- found in the heart, acts like rhythmic smooth muscle, modulated by neural activity and hormones has intercalated discs

3) Skeletal muscle - move us around and responsible for most of our behavior; most attached to bones at each end via tendons

Most muscles work in pairs, and when a muscle works it needs to have an agonist and an antagonist. Antagonistic pairs are located in opposite sides of a joint or bone

This provides movement in opposing directions.

Actin is a thin filliment conected to the Z line

Myosin is a thick filliment conected to the M line That pulls the actin towards the M line during contraction

Sarcomere is Z line to Z line

Z line connection point fo actin

M line connection point fo myosin

Crossbridges form atares whee actin and myosin overlap

Contactions bring Z lines closer together.

1. AP reaches NMJ & activate synapse.

2.MAP travels along sarcolemma & down T-tubules.

3.MAP activates protein on SR - SR releases Ca.

4.Ca binds to troponin-tropomyosin releases myosin binding on actin.

5.myosin binds to actin (cross-bridge formation )

6. myosin pulls actin in ( powerstroke)

7.ATP required to break and reset myosin head.

Real life movement

1.Tendons will optimize sacomere length

2.Isometric contraction to match the load ( same length) building tension

3.Isotonic contraction to move load

4.Tendons reoptimize sarcomere length.

slow twitch low level force (back support) lots of mitochondria & myoglobin never fatigue.

fast twitch generates moderate tension for walking or standing some mitochondria & myoglobin .

super fast twitch generates high tension for running o jumping litle to no mitochondria & myoglobin

Describe the flow of blood in the heart, and how this relates to the manner in which the heart beats.

The blood first enters the right atrium. It then flows through the tricuspid valve into the right ventricle. When the heart beats, the ventricle pushes the blood through the pulmonic valve into the pulmonic artery. This artery is unique: It is the only artery in the human body that carries oxygen-poor blood.

The pulmonic artery carries blood to the lungs where it “picks up” oxygen, and leaves the lungs and returns to the heart through the pulmonic vein. The blood enters the left atrium, then descends through the mitral valve into the left ventricle. The left ventricle then pumps blood through the aortic valve, and into the aorta, the blood vessel that leads to the rest of the body

Describe the makeup of hemoglobin. How does it carry O2?