Biology Assignment: Digestion, Smoking Impact, and Cellular Biology

This assignment provides comprehensive answers to three key questions in general biology. The first answer details the digestion process of a cheese sandwich, breaking down the digestion of carbohydrates, proteins, and fats, including the enzymes and locations involved. The second answer focuses on the effects of cigarette smoke, detailing how it reduces mucociliary transport, alters mucous production, and causes structural and functional alterations in the respiratory epithelium, including changes to cell viability and regeneration. The third answer describes the structure and function of ciliated epithelial cells in the trachea, skeletal muscle cells, and the two types of bone tissue (compact and spongy), highlighting their unique characteristics and roles in the body, along with the importance of the structures and processes involved.

Running head: GENERAL BIOLOGY
GENERAL BIOLOGY
Name of the disease:
Name of the student:
Author note:

1GENERAL BIOLOGY
Answer 1:
Cheese sandwich comprises of three important nutrients other than vitamins and minerals. They
are carbohydrate in the form of wheat starch present in the bread. Besides, cheese contains
protein and fat. The main process of their digestion is:
CARBOHYDRATE:
A. Starch digestion begins in the mouth by ptyalin which is salivary alpha amylase.
B. It hydrolyses starch into alpha dextrin.
C. This is then broken in to the maltose and malto-triose form with the help of the gluco-
amylase (alpha dextrinases).
D. The products of the ptyalin and that of glucoamylase are further broken down into
corresponding monosaccharide by maltase, isomaltase, sucrase and lactase in the brush
borders of small intestine (Bernardi and Sattin 2015).
E. Absorption occurs from the epithelium of the small intestine consisting of villi by active
transport.
F. After assimilation they are transported to blood.

2GENERAL BIOLOGY
PROTEIN
A. Stomach helps in the production of hydrochloric acid which helps in the activation of the
protein digestion
B. Stomach secretes an enzyme called the pepsin as well as the protease which helps in the
removal of bonds that holds together the long chains of amino acids of the proteins.
C. The pancreas helps in the release of the trypsin and chymotrypsin
D. All of them enter the small intestine where proteins form polypeptides
E. Here they are further broken down into the amino acids by various exopepeptidases and
dipeptidases (Santos et al. 2013).
F. Amino acids are absorbed form the small intestine
G. They are assimilated and transported through blood to cells
FATS:
A. Its starts in the mouth where some form of lingual lipase initiates fat digestion forming
diglycerides from short chain lipids.
B. Fats are mainly digested in small intestine
C. Presence of fat in small intestine initiates production if hormones which stimulates bile
form liver and pancreatic amylase form pancreas
D. Emulsification and absorption of fatty acids (Mata-Alvarez et al. 2014)
E. Assimilated and transported to cells.

3GENERAL BIOLOGY
Answer 2:
It has been found out by different researches that the components of cigarette smoke cause a
deep reduction of mucociliary transport. Cotinin which is one of the harmful metabolite of
nicotine is responsible for reducing the ciliary beat of epithelial cells of the respiratory tact.
However no such thing is noticed in a non smoker. Moreover it also results in the changes of
mucous production. This is mainly due to the metaplastic alteration that occurs in the respiratory
mucosa mainly due to the increase of the goblet cells both in number as well as in size. Therefore
it results in consequent increase in upper airway secretion. Moreover others have said that
smoking results in inhibition of the chloride transport in the epithelia cells which are not
observed in the non smokers.
Besides functional alterations, structural alterations of the respiratory epithelium results from the
cigarette smoking. It results in the reduction of cell viability and at the same time causes the
induction of the apoptosis of the respiratory hair cells. Depending upon the concentration of
cigarette smoking they can also cause the mitogenic effects and the prop-apoptopic phase. Upon
injury, impairment of epithelia regeneration may also take place (Tilley et al. 2016). Moreover, it
also leads to the morphological alteration of the epithelium of the entire respiratory tracts which
does not occur in non smokers. It also may result in hyperplasia in lower concentration to even
loss of cilia and metaplasia in higher concentration along with keratinisation. Many researchers
are also of the opinion that sub mucosal thickening as well as inflammation takes place with
mononuclear and inflammatory cells and neutrofilic cells. Even researchers are of the opinion

4GENERAL BIOLOGY
that such a mucosa inflammatory reaction persists up to seven months even after withdrawn.
Ultra structural cilia abnormalities are also found. Many also suggest that it has negative impact
of the ciliogenesis process in dose dependent manner to the respiratory epithelia in maturation
and differentiation phases (Nyonoa et al. 2014). All these do not occur in non smokers.
Answer 3:
A. The ciliated epithelial cells of the trachea are columnar and have numerous cilia at their
apical surface. The cilium mainly helps in generating a ciliary beating which helps in the
sweeping of the mucus and the dust which gets carried to the bronchi as well as the
tracheas towards the pharynx where they would be swallowed. Among the ciliated cells,
there are the goblet cells which are the main source of mucous moistening the epithelial
surface. This helps the ciliated cells to function. The cells are columnar to increase the
surface and more mucus production is possible (Rock et al. 2017).
B. Skeletal muscles cells are usually long as they are formed form the fusion of different
smaller cells during fetal development. So they contain many nuclei and are long. The
stripes that are present in the cells are mainly due to the regular arrangement of the actin
and myosin proteins within the cells. They form structures called myofibrils they are
responsible for providing the skeletal muscles’ great strength as well as to develop the
ability to pull different incredible force and proper the body.
C. The skeletal tissue contains two important types of bone. One is the compact bone that
mainly forms the outer layer and contains of spaces. They mainly help in providing
protection as well as support to the bones surrounding whim lies the compact bone. They

5GENERAL BIOLOGY
also help to enable the long bones to bear stress placed on them by the body weight and
to which limbs are used. The spongy bone contains the trabeculae which contain
lamellae, osteocytes, lacunae and canaliculi with spaces between them filled with red
bone marrow. Blood vessels which are coming from the periosteum which allows the
osteocytes to receive nourishments form the blood which passes through the bone
marrow.

6GENERAL BIOLOGY
References:
Bernardi, A. and Sattin, S., 2015. Carbohydrates: A phenol sandwich fights diabetes. Nature
chemical biology, 11(9), p.635.
Mata-Alvarez, J., Dosta, J., Romero-Güiza, M.S., Fonoll, X., Peces, M. and Astals, S., 2014. A
critical review on anaerobic co-digestion achievements between 2010 and 2013. Renewable and
Sustainable Energy Reviews, 36, pp.412-427.
Nyunoya, T., Mebratu, Y., Contreras, A., Delgado, M., Chand, H.S. and Tesfaigzi, Y., 2014.
Molecular Processes that Drive Cigarette Smoke–Induced Epithelial Cell Fate of the
Lung. American journal of respiratory cell and molecular biology, 50(3), pp.471-482.
Rock, J.R., Onaitis, M.W., Rawlins, E.L., Lu, Y., Clark, C.P., Xue, Y., Randell, S.H. and Hogan,
B.L., 2017. Basal cells as stem cells of the mouse trachea and human airway
epithelium. Proceedings of the National Academy of Sciences, 106(31), pp.12771-12775.
Santos, H.M., Kouvonen, P., Capelo, J.L. and Corthals, G.L., 2013. On‐target ultrasonic
digestion of proteins. Proteomics, 13(9), pp.1423-1427.
Tilley, A.E., Staudt, M.R., Salit, J., Van de Graaf, B., Strulovici-Barel, Y., Kaner, R.J., Vincent,
T., Agosto-Perez, F., Mezey, J.G., Raby, B.A. and Crystal, R.G., 2016. Cigarette smoking
induces changes in airway epithelial expression of genes associated with monogenic lung
disorders. American journal of respiratory and critical care medicine, 193(2), pp.215-217.

7GENERAL BIOLOGY