Biology Chapter on Antibiotic Resistance & Immunity

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What happens to the population of non-resistant bacteria when antibiotic concentration increases?

It decreases at the end of 24 hours. (correct)

It remains unchanged over time.

It increases then decreases.

It increases significantly.

Which statement about the relationship between antibiotic concentration and resistance is true?

Higher antibiotic concentrations do not affect resistant bacteria.

Resistance levels decrease with higher antibiotic concentrations.

Non-resistant bacteria thrive at high concentrations of antibiotics.

The proportion of resistance increases with higher antibiotic concentrations. (correct)

What is the correct first step in a primary immune response?

B-lymphocyte differentiation

T-lymphocyte activation

Antigen presentation by macrophages (correct)

Cytokines released by T-helper cells

Which of the following sequences describes the steps of a primary immune response accurately?

Antigen presentation, cytokines released, B-lymphocyte differentiation Signup and view all the answers

Which feature is true regarding the antigen-binding sites in antibodies?

They have variable amino acid sequences for different antigens. Signup and view all the answers

What is represented by X in the monoclonal antibody production diagram?

B-lymphocytes Signup and view all the answers

What is the primary role of T-helper cells during the immune response?

They release cytokines to activate B-lymphocytes. Signup and view all the answers

In what way does increasing the antibiotic concentration affect resistant bacteria?

It always increases their numbers. Signup and view all the answers

Which statement accurately describes the composition of hemoglobin?

Hemoglobin consists of two alpha chains and two beta chains that form a quaternary structure. Signup and view all the answers

What is the maximum number of oxygen molecules that one hemoglobin molecule can transport?

Four Signup and view all the answers

Which feature of the hemoglobin molecule allows it to bind and release oxygen?

The presence of hydrophobic R-groups surrounding the iron ion. Signup and view all the answers

Which process does not require energy from ATP?

Facilitated diffusion Signup and view all the answers

How many iron ions are associated with each chain of hemoglobin?

One per chain Signup and view all the answers

What structural feature allows hemoglobin to adopt a nearly spherical shape?

The hydrophobic interactions between amino acids. Signup and view all the answers

What type of molecule is hemoglobin classified as?

A protein Signup and view all the answers

In the context of hemoglobin, what does 50% saturation refer to?

The percentage of oxygen molecules that are bound to hemoglobin. Signup and view all the answers

During which stage of mitosis are spindle fibers at their maximum length?

Metaphase Signup and view all the answers

Which of the following anticodons could specify an amino acid other than threonine?

UGU Signup and view all the answers

What type of bond does DNA polymerase catalyze during DNA replication?

Phosphodiester bonds between nucleotides Signup and view all the answers

What are the coding sequences formed during mRNA modification called?

Exons Signup and view all the answers

At which point during the process of plant transport does sucrose mass flow occur?

During translocation Signup and view all the answers

Which statement correctly describes DNA replication preparation?

It occurs before the cell reaches its maximum size. Signup and view all the answers

Which phase of mitosis is primarily characterized by the condensation of chromosomes?

Prophase Signup and view all the answers

Which of the following results occurs after the non-coding sequences are removed during RNA processing?

Joining of coding sequences Signup and view all the answers

What happens in the heart at point X during the cardiac cycle?

The atrioventricular valves close. Signup and view all the answers

How many times must a carbon dioxide molecule cross a cell surface membrane to reach an air space in an alveolus?

3 Signup and view all the answers

Which letter indicates the location of the atrioventricular node in the heart diagram?

C Signup and view all the answers

What components of blood are typically present in tissue fluid?

Some proteins and sodium ions. Signup and view all the answers

Which process maintains the steep concentration gradients necessary for effective gas exchange in the lungs?

Ventilation of the lungs. Signup and view all the answers

What primarily triggers the opening of the semilunar valves in the heart?

Increased pressure in the ventricles. Signup and view all the answers

What is the primary function of the phagocytes found in tissue fluid?

Engulfing pathogens. Signup and view all the answers

Which valves are responsible for preventing backflow into the atria during ventricular contraction?

Atrioventricular valves. Signup and view all the answers

What effect does increasing antibiotic concentration have on the total population of bacteria over time?

It consistently decreases the total population. Signup and view all the answers

Which of the following observations can be made regarding resistant bacteria at an antibiotic concentration of 600 mg dm–3?

The resistant population initially increases and then stabilizes. Signup and view all the answers

At an antibiotic concentration of 90 mg dm–3, what can be said about the behavior of the resistant population over the 24-hour period?

It increases initially and then plateaus. Signup and view all the answers

Which of the following trends is observed in the population of bacteria at 215 mg dm–3 concentration after 24 hours?

Total population decreases significantly while resistant population grows. Signup and view all the answers

What can be concluded about the relationship between antibiotic concentration and the development of resistance in bacteria?

Resistance can arise even at low concentrations of antibiotics. Signup and view all the answers

Upon examining the effects of the antibiotic, which statement about the population dynamics is true?

The resistant population tends to increase with higher antibiotic concentrations. Signup and view all the answers

What happens to antibiotic resistance levels in bacteria when the antibiotic concentration reaches 0 mg dm–3?

Resistance levels decline as no selective pressure exists. Signup and view all the answers

Which conclusion can be drawn regarding the impact of time on the development of antibiotic resistance?

Resistance increases steadily over time with consistent exposure. Signup and view all the answers

At an antibiotic concentration of 0 mg dm–3, what is the most likely impact on the overall growth of the bacterial population?

The bacterial population continues to grow indefinitely. Signup and view all the answers

How does the presence of resistant bacteria affect the effectiveness of antibiotic treatment over time?

It renders the antibiotic ineffective in the long run. Signup and view all the answers

Study Notes

Antibiotic Resistance

Increasing the concentration of antibiotics decreases the population of non-resistant bacteria over 24 hours.
Increasing the concentration of antibiotics leads to an increase in the proportion of antibiotic-resistant bacteria.
Increasing the concentration of antibiotics does not always increase the number of resistant bacteria.

Immune Responses

Antigen presentation by macrophages leads to the release of cytokines from T-helper cells, which activate B-lymphocytes.
This activation triggers B-lymphocyte differentiation into plasma cells, resulting in antibody production.
Antibodies have variable amino acid sequences within their antigen-binding sites, allowing them to recognize and bind to different antigens.

Monoclonal Antibody Production

Hybridoma cells are created by fusing B-lymphocytes with cancer cells.

Haemoglobin

Haemoglobin consists of four polypeptide chains, each containing a haem group with an iron ion.
The iron ions in each chain, at 50% saturation, can associate with oxygen molecules, forming oxyhaemoglobin.
Hydrophobic R-groups of amino acids in each chain point towards the centre of the molecule.

Cell Transport

Facilitated diffusion does not require energy from ATP.
The rate of entry of molecule X is independent of the concentration of ATP in the cytoplasm.

Mitosis

Centromeres detach from spindle fibres during anaphase, resulting in daughter chromosomes being pulled to opposite poles of the cell.

Genetic Code

The mRNA codons ACU, ACC, ACA and ACG all code for the same amino acid, threonine.
Anticodons must be complementary to the codons.

DNA Replication

DNA polymerase catalyses the formation of phosphodiester bonds between nucleotides during DNA replication.

Gene Expression

Coding sequences in eukaryotic RNA molecules are called exons.

Plant Transport

Sinks for sucrose transport by mass flow in plants include growing roots, stems, fruits, and flowers.

Heart

The atrioventricular node is located in the right atrium.

Blood and Tissue Fluid

Tissue fluid contains phagocytes, some proteins, and sodium ions.

Gas Exchange

Carbon dioxide that is transported in red blood cells must cross at least four cell surface membranes to reach an air space in an alveolus.
Maintaining the steep concentration gradients for efficient gas exchange requires ventilation, maintaining a high surface area for gas exchange and a short diffusion distance.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers important concepts related to antibiotic resistance, immune responses, monoclonal antibody production, and the structure of haemoglobin. Test your understanding of how antibiotics affect bacteria populations and the immune system's response through antibodies. Suitable for biology students looking to reinforce their knowledge of these critical topics.