I Apinaya Amuthalingham I BTEC Applied Science I Biology I Unit 12 I Diseases and Infections I
Learning Aim A I
Pathogens and Communicable (Infectious) Diseases:-
Virus:-
A virus is an infectious microbe that can replicate itself. Viruses are non-living cells that reproduce by taking
over living cells. For example, it can infect cells and other components of a host’s body and make millions
of copies of itself. So, it can spread itself further from the infected virus site in the host’s body.
- Transmission: A virus can be transferred through direct and indirect contact. The virus must enter
the host through a portal of entry and replicate within the host. The virus can then be transferred to
another host by exiting through the portal. For example virus can be transmitted through droplet
transmission, sexual intercourse, and contaminated areas.
- Mechanism: A virus has a genetic material and it must be ejected into the portal of entry of the
target cell and replicate itself. It then spreads itself through the host and targets it’s vital organs, that
can contain diseases, and the spread itself of the host’s site of the virus shedding in it’s surrounding
environment. This then turns the genetic material into viruses.
- Example Of A Disease: Ebola.
Ebola:-
Ebola is a rare virus that is infectious. mostly found in parts of Africa. Ebola is caused by a virus that's
initially caught through exposure to the body fluids and tissues of infected animals. The virus is then spread
from host to host. After 21 days of infection, the characteristic features of ebola, or symptoms, can begin to
manifest in two days. They can suddenly manifest as flu symptoms. Those symptoms are:regulated
- Fever.
- Stomach Pain.
- Diarrhoea.
- Skin Rashes.
- Blood in Feces.
- Bruises all over the Body.
- Bleeding through the Eyes, Ears, Nose and Mouth.
Ebola's life cycle typically begins with mild symptoms such as fever, aches and pains all over the body, or
fatigue and progresses to severe symptoms such as diarrhea and constant vomiting if not treated.
The biological mechanisms of ebola are where the virus enters the host’s body through the mucous
membrane and infects many cells. It then embeds itself in the surface area of the cells through the
glycoprotein spikes that bind to the cell-fusion fin between the virus cell and the host’s cell membrane. This
allows the virus to enter the host's cytoplasm and release its contents. The ebola virus attacks the kidneys
and spleen, where fluids and chemical balances are and make the made to help clot the blood, and kills
the genetic cells within them.
Fungus:-
1
, Fungus is a member of the eukaryotic cells that also consists of microorganisms such as yeast, molds, and
mushrooms. These microorganisms are classified as fungi. They contain a cell wall. They grow as single
cells and have threadlike filaments. Fungi are responsible for breaking down organic matter and releasing
carbon, oxygen, nitrogen, and phosphorus into the surrounding environment of the atmosphere.
- Transmission: Fungus can be transmitted through direct contact or through spores. For example,
through direct skiing contact infections can be transferred or through indirect contact with
contaminated areas. Some fungis can be reproduced through spores in the air. This is because
fungus is a microscopic seed.
- Mecahnism: Fungi secretes enzymes that digest the surrounding cells. The products are then
reabsorbed for resources, it then facilitates and multiplieswithin the host.
- Example Of A Disease: Candidiasis.
Candidiasis:-
Candidiasis is a fungal infection that is caused by yeast, a type of fungus. This is called Candida. Candida
can infect humans; Candida primarily lives on the host's skin and inside their bodies.
The characteristic features of candidiasis depend on where it is located on the host. Usually, it starts with
irritation, itching, and white discharge. There are different types of characteristic features; for women, they
live mainly in the vagina or other body parts, while for men, they live in their genitals and other body parts.
Candidiasis Characteristic Features In Candidiasis Characteristic Features In
Females Males
● White Vaginal Discharge. ● White Discharge.
● Itching and Irritation Around Genitals. ● Unpleasant Smell.
● Soreness and Stinging Sensation ● Irritation and Burning Sensation Around
During Sexual Intercourse. Genitals.
● Can Affect Other Areas Of Skin ● Can Affect Other Areas Of Skin.
● Itchy and Painful Rashes. ● Itchy and Painful Rashes.
The yeast cells live on the host's surface area of their cells via adhesives, which is the biological
mechanism of candidiasis. If any direct or indirect contact causes the host’s cells to trigger the transition of
yeast, it can lead to direct growth. It takes in fungus from the host’s cell through endocytosis.
Protozoa:-
2
Learning Aim A I
Pathogens and Communicable (Infectious) Diseases:-
Virus:-
A virus is an infectious microbe that can replicate itself. Viruses are non-living cells that reproduce by taking
over living cells. For example, it can infect cells and other components of a host’s body and make millions
of copies of itself. So, it can spread itself further from the infected virus site in the host’s body.
- Transmission: A virus can be transferred through direct and indirect contact. The virus must enter
the host through a portal of entry and replicate within the host. The virus can then be transferred to
another host by exiting through the portal. For example virus can be transmitted through droplet
transmission, sexual intercourse, and contaminated areas.
- Mechanism: A virus has a genetic material and it must be ejected into the portal of entry of the
target cell and replicate itself. It then spreads itself through the host and targets it’s vital organs, that
can contain diseases, and the spread itself of the host’s site of the virus shedding in it’s surrounding
environment. This then turns the genetic material into viruses.
- Example Of A Disease: Ebola.
Ebola:-
Ebola is a rare virus that is infectious. mostly found in parts of Africa. Ebola is caused by a virus that's
initially caught through exposure to the body fluids and tissues of infected animals. The virus is then spread
from host to host. After 21 days of infection, the characteristic features of ebola, or symptoms, can begin to
manifest in two days. They can suddenly manifest as flu symptoms. Those symptoms are:regulated
- Fever.
- Stomach Pain.
- Diarrhoea.
- Skin Rashes.
- Blood in Feces.
- Bruises all over the Body.
- Bleeding through the Eyes, Ears, Nose and Mouth.
Ebola's life cycle typically begins with mild symptoms such as fever, aches and pains all over the body, or
fatigue and progresses to severe symptoms such as diarrhea and constant vomiting if not treated.
The biological mechanisms of ebola are where the virus enters the host’s body through the mucous
membrane and infects many cells. It then embeds itself in the surface area of the cells through the
glycoprotein spikes that bind to the cell-fusion fin between the virus cell and the host’s cell membrane. This
allows the virus to enter the host's cytoplasm and release its contents. The ebola virus attacks the kidneys
and spleen, where fluids and chemical balances are and make the made to help clot the blood, and kills
the genetic cells within them.
Fungus:-
1
, Fungus is a member of the eukaryotic cells that also consists of microorganisms such as yeast, molds, and
mushrooms. These microorganisms are classified as fungi. They contain a cell wall. They grow as single
cells and have threadlike filaments. Fungi are responsible for breaking down organic matter and releasing
carbon, oxygen, nitrogen, and phosphorus into the surrounding environment of the atmosphere.
- Transmission: Fungus can be transmitted through direct contact or through spores. For example,
through direct skiing contact infections can be transferred or through indirect contact with
contaminated areas. Some fungis can be reproduced through spores in the air. This is because
fungus is a microscopic seed.
- Mecahnism: Fungi secretes enzymes that digest the surrounding cells. The products are then
reabsorbed for resources, it then facilitates and multiplieswithin the host.
- Example Of A Disease: Candidiasis.
Candidiasis:-
Candidiasis is a fungal infection that is caused by yeast, a type of fungus. This is called Candida. Candida
can infect humans; Candida primarily lives on the host's skin and inside their bodies.
The characteristic features of candidiasis depend on where it is located on the host. Usually, it starts with
irritation, itching, and white discharge. There are different types of characteristic features; for women, they
live mainly in the vagina or other body parts, while for men, they live in their genitals and other body parts.
Candidiasis Characteristic Features In Candidiasis Characteristic Features In
Females Males
● White Vaginal Discharge. ● White Discharge.
● Itching and Irritation Around Genitals. ● Unpleasant Smell.
● Soreness and Stinging Sensation ● Irritation and Burning Sensation Around
During Sexual Intercourse. Genitals.
● Can Affect Other Areas Of Skin ● Can Affect Other Areas Of Skin.
● Itchy and Painful Rashes. ● Itchy and Painful Rashes.
The yeast cells live on the host's surface area of their cells via adhesives, which is the biological
mechanism of candidiasis. If any direct or indirect contact causes the host’s cells to trigger the transition of
yeast, it can lead to direct growth. It takes in fungus from the host’s cell through endocytosis.
Protozoa:-
2
