Living Vs Non-Living Objects, Transport Mechanisms, And Connective Tissues

Cells, Tissues and Organs

Question  1

The plasma membrane consists of a phospholipids, proteins and cholesterol and proteins fluid. It also has glycolipids glycoproteins extending from its outward-facing surface. The plasma membrane is referred to as a mosaic model because it consists of a phospholipid which has different protein molecules floating within it. Described to be partly fluid the plasma membrane has some of its parts moving around freely when unattached to other cell parts.

Question  2

Question  3

Question  4

Question  5

The 3 muscle tissue types include cardiac, skeletal and smooth muscles. The cardiac muscle cells located in heart are striated and are usually under involuntary control.

The smooth muscles are within hollow visceral organ walls except in the heart. They are spindle-shaped and also under the body’ involuntary control.  Skeletal muscles are found attached to the body skeleton. Skeletal muscle fibres are striated but under voluntary control.

Question  6

Tissue repair occurs in phases. The inflammatory phase as the first one occurs between day 1 and 7 after injury where acute inflammation and bleeding initially occurs resulting into pain, swelling, heat and redness. Inflammation breaks down damaged cells and digests them in preparation for the next phase.  The second phase is referred to as fibroblastic repair phase which begins from Day 4 till 6 weeks. The damaged tissue starts being repaired through a disorganized laying down of collagen fibres forming a scar tissue that is weaker and/or less flexible as compared to the surrounding normal tissues. The remodelling phase is the last phase that starts from 2 to 3 weeks after injury. The quality strength and organization of the tissue improve as the cellular collagen fibre organization occurs with increased strength of the bonds between them. Addition of stress to the tissues at this time helps realign those fibres along proper stress line making the tissues to be in position to accommodate more loads placed on them.

Part C: Homeostasis and Disease Progression

Question  1

A molecule is usually formed by the joining of two or more atoms chemically. On the other hand, compound refers to a molecule consisting of at least two elements that are different.

H₂O above is both a molecule and a compound.

Question  2

Chemical reaction refers to process where a substance or more as reactants; are converted to one and/or more substances different from the reactants referred to as product(s).

From the above equation, H₂O and CO₂ are reactants which react to form H₂CO₃ (product).

Question  3

H₂CO₃ is an acid while the HCO₃^– is a weak base. This is because the released hydrogen ion remains attached to attached thus not free in solution meaning there is no pH change.

 Question  4

An increase in carbon dioxide increases the formation of carbonic acid. Carbonic acid is however always in equilibrium with bicarbonate in solution.

Significant carbonic acid and/or bicarbonate amounts lead to the formation of a buffer written as shown.  
H₂CO₃ + H₂O   H₃O⁺ + HCO₃^–

The blood buffer consisting of high base concentration helps in neutralizing the carbonic acid. Where more carbon dioxide is present, carbonic acid concentration lowers in the blood. The instability of carbonic acid in aqueous solutions makes some of it to decompose forming water and carbon dioxide. The respiratory system is responsible for removing the carbon dioxide. 
Question  5

Loss of normal control of cell division results in to abnormal cell division. In this case, basal cells begin to divide faster than required to replenish those cells being shed. Each of the newly formed cells also has the capacity to get divided thus resulting in an increase in the dividing cell numbers. This is simply referred to as cancer.

Question  6

· Smoking(Nicotine)

· Radiation

· Carcinogenic chemicals

· Exposure to viruses and/or hormones

Question  7

Question  9: Signs & Symptoms of Hyperthermia

· Coma

· Fainting

· Confusion,

· Fever

· Muscle cramps

· Nausea

· Faster hear rate.

Part D: Integumentary System

Question  1

The integumentary system comprises of the glands, hair, nails, skin, and nerves. It major function includes acting as a barrier and protection of the body from any factors in the external environment. It also retains body fluids, protects against diseases, eliminates wastes, and regulates the body temperature.

Question  2

Signs and Symptoms Of Skin Cancers, including Melanoma

· Non-healing sores

· Pigment spread from spot border to the surrounding skin

· Redness occurs beyond the border of the sore spot

· Itchiness, tenderness and pain

· Changes in mole surface

Question  3

Cellular changes in melanoma are caused by ultraviolet (UV) rays which damage skin cells’ DNA. The damage disrupts normal cell division leading to abnormal cell division where basal cells of the skin develop faster than cells that need normal shed-off. These cells can even divide further forming tumours as melanoma. The loss of normal control mechanism caused by triggers normally turns on oncogenes while also turning off the skin’s tumour suppressor genes. This leads to melanoma where there is abnormal cell division as stated above.

Question  4:

· Ultraviolet rays from the sun and from tanning beds

· Radiation

· Chemical solvents

Question  5

Causes of Burns

· Fire

· Electrical current

· Hot liquid/steam

· Chemicals

Classification of Burns

1. First degree burns-only epidermis burnt

2. Second degree burns-epidermis and part of dermis

3. Destroys epidermis, dermis and even the subcutaneous layer of skin.

Part E: Musculo-skeletal System

Question  1

Function of the skeletal system

· Support-Leg, pelvic and vertebral column bones hold the body up.

· Protection-The bones enclose and also protect lungs, brain, heart, bone marrow and the spinal cord.

· Movement-Skeletal muscles facilitate movement of legs and arms. Also enable ventilation through facilitation rib movement.

Question  2

The bones forming the skeleton function as reservoirs for calcium, phosphorus and essential minerals. Muscles contain troponin protein which helps to hold tropomyosin on the actin filament in place. Muscle contraction needs troponin and the tropomyosin to be moved in order to reveal myosin-binding sites. At this point, calcium mobilized from bones triggers the movement of the two proteins. The binding of calcium to troponin protein leads to a change in the shape of troponin molecule effecting contraction.

Question  3

Myofibril consists of thick and/or thin myofilaments which give the striped appearance of the muscle. The thick filaments consist of myosin while the thin filaments are mainly actin including tropomyosin and troponin.The sarcoplasmic reticulum releases calcium ions into the muscle so as to bind to troponin, and this causes tropomyosin shifting actin from the filament face producing contraction.

Question  4

Question  5

Aging leads to osteoporosis where the bone density decreases as a result of decrease in the bone extracellular matrix. Contraindicated manual therapies among people with osteoporosis include twisting movements, exercise involving abrupt/explosive loading, and those with high-impact loading.

Question 6: Signs and Symptoms of Fibromyalgia.

· Pain

· Lack of sleep

· Morning stiffness

· Problems with cognitive memory

· Headaches

· Restless legs

· Painful menstrual periods