JOSS Bio Lesson 1 Flashcards
What is the definition of an antigen?
A substance that is capable of stimulating an immune response. This means your immune system does not recognize the substance, and is trying to fight it off. An antigen may be a substance from the environment, such as chemicals, bacteria, viruses, or pollen.
What is the balanced cellular equation for cellular respiration?
C 6 H 12 O 6 + 6 O 2 –> 6 CO 2 + 6 H 2 O + ATP is the complete balanced chemical formula for cellular respiration.
Contast prokaryotes and eukaryotes.
Prokaryotes are always unicellular, while eukaryotes are often multi-celled organisms. Additionally, eukaryotic cells are more than 100 to 10,000 times larger than prokaryotic cells and are much more complex. The DNA in eukaryotes is stored within the nucleus, while DNA is stored in the cytoplasm of prokaryotes.
What are some first line defences of the human immune system?
Innate immunity is the host’s first line of defense and is intended to prevent infection and attack the invading pathogens. This nonspecific mechanism is fast (minutes to hours) while the adaptive response takes longer (days to weeks).
Describe innate immunity
Anatomic (skin and mucous membrane), physiologic (temperature, low pH and chemical mediators), endocytic and phagocytic, and inflammatory.
What is the mode of transmission of disease?
The term modes of transmission refer to how an infectious agent, also called a pathogen, can be transferred from one person, object, or animal, to another. Viruses, bacteria, parasites, or fungi can spread infectious diseases.
What is a catalase in an enzyme?
Catalase is a common enzyme found in nearly all living organisms exposed to oxygen which catalyzes the decomposition of hydrogen peroxide to water and oxygen. It is a very important enzyme in protecting the cell from oxidative damage by reactive oxygen species.
How do Enzymes respond to heat?
Because enzymes are proteins, they are denatured by heat. Therefore, at higher temperatures (over about 55°C in the graph below) there is a rapid loss of activity as the protein suffers irreversible denaturation.
How is communication transmitted along the cells?
Cells communicate by sending and receiving signals. Signals may come from the environment, or they may come from other cells. In order to trigger a response, these signals must be transmitted across the cell membrane. Sometimes the signal itself can cross the membrane.
How does communication cross from one cell to another?
Cells communicate by sending and receiving signals. Signals may come from the environment, or they may come from other cells. In order to trigger a response, these signals must be transmitted across the cell membrane. Sometimes the signal itself can cross the membrane.
What are feedback loops?
Feedback loops are biological mechanisms whereby homeostasis is maintained. This occurs when the product or output of an event or reaction changes the organism’s response to that reaction. Positive feedback occurs to increase the change or output: the result of a reaction is amplified to make it occur more quickly.
How do plasma B cells respond to bacterial infection?
Some of the B cells become plasma cells capable of producing antibodies.
Describe enzymes
An enzyme is a biological catalyst and is almost always a protein. It speeds up the rate of a specific chemical reaction in the cell. The enzyme is not destroyed during the reaction and is used over and over.
A product of the light-dependent reactions is…
The exergonic light-dependent reactions of photosynthesis convert light energy into chemical energy, producing ATP and NADPH.
Why do leaves lose turgidity?
Turgor is what makes living plant tissue rigid. Loss of turgor, resulting from the loss of water from plant cells, causes flowers and leaves to wilt. Turgor plays a key role in the opening and closing of stomata (see stoma) in leaves.
This electron scanning image is of….
Choroplast
This electron scanning image is of….
Mitochondrion
