Lab 1: Scientific Report Writing

Questions and Answers

What could be a potential reason for hybridization between the green turtle and hawksbill turtle in the Southeast Pacific?

Limited availability of breeding partners for both species (correct)

Decreased ocean temperatures affecting breeding habits

Diverse genetic mutations within each species

Improved feeding conditions in the region

Which aspect of a scientific report assesses the clarity of communication regarding its findings?

Results

Purpose

Importance (correct)

Abstract

Which factor affected the rate of diffusion in the experiment with potassium permanganate?

Size of the test tubes used

Temperature of the environment

Concentration of potassium permanganate

Purity of the water it was dissolved in (correct)

How does establishing hypotheses contribute to the research process?

It provides a framework for conducting experiments Signup and view all the answers

What was the result of the diffusion of potassium permanganate in distilled water compared to tap water?

It occurred faster in distilled water Signup and view all the answers

Which component of a scientific report helps identify the main objective of the research?

Purpose Signup and view all the answers

What characteristic is essential for the results section of a scientific report?

It should clearly relate results to the hypothesis Signup and view all the answers

What is a strength of documenting the research process in scientific reports?

It allows replication and validation of results by others Signup and view all the answers

What is the purpose of covering the mouth of the test tube with longganisa skin?

To create a semipermeable barrier for osmosis Signup and view all the answers

Which solution is considered hypotonic in the experiment with red blood cells?

0.07 M NaCl solution Signup and view all the answers

What result is observed after immersing the test tube containing the sucrose solution in distilled water?

Increase of weight and height Signup and view all the answers

What happens to the water during the process of osmosis in this experiment?

Water moves from low to high solute concentration Signup and view all the answers

What does an isotonic solution mean in the context of this experiment?

It has an equal concentration of solutes as the cell Signup and view all the answers

What is the primary role of cholesterol in the cell membrane?

Regulates fluidity or viscosity Signup and view all the answers

Which type of transport requires energy to move substances across the cell membrane?

Active transport Signup and view all the answers

Which type of membrane protein is involved in molecule transfer and can penetrate the hydrophobic interior of the lipid bilayer?

Integral membrane proteins Signup and view all the answers

What is the effect of a hypertonic solution on plant cells?

Cells undergo plasmolysis Signup and view all the answers

Which of the following correctly describes the sodium-potassium pump?

Maintains a negative membrane potential by moving 3 Na+ out and 2 K+ in Signup and view all the answers

What characterizes a graded potential in neurons?

It is caused by stimulation from neurotransmitters Signup and view all the answers

Which type of fatty acid results in a liquid state at room temperature?

Unsaturated fatty acids Signup and view all the answers

What occurs during endocytosis in a cell?

Substances are engulfed into vesicles Signup and view all the answers

Which molecules primarily make up the structure of the cell membrane?

Phospholipids, proteins, and carbohydrates Signup and view all the answers

What is the typical resting membrane potential of a neuron?

-70 mV Signup and view all the answers

In which type of membrane transport is a hydrophilic pore created by proteins?

Facilitated diffusion Signup and view all the answers

What happens to cells in an isotonic solution?

Cells maintain their shape and volume Signup and view all the answers

Which type of endocytosis involves the ingestion of liquid particles?

Pinocytosis Signup and view all the answers

What is the main function of glycolipids in the cell membrane?

Cell recognition and communication Signup and view all the answers

Which dye diffused the farthest in the colloid experiment?

Methylene blue Signup and view all the answers

What was the purpose of using dialysis in the experiments?

To test the presence of chloride and calcium ions Signup and view all the answers

Which factor does NOT affect diffusion time in the colloid experiment?

Color of the dye Signup and view all the answers

What was used to secure the dried longganisa skin during the dialysis experiment?

Thread or a rubber band Signup and view all the answers

During the dialysis experiment, which test tube produced a white, cloudy precipitate first?

The test tube with silver nitrate Signup and view all the answers

How does molecular size affect diffusion through a membrane?

Larger molecules move slower than smaller molecules Signup and view all the answers

Which reagent was added to the first test tube during the dialysis experiment to test for chloride ions?

Silver nitrate Signup and view all the answers

In the context of diffusion, which factor would increase the diffusion rate?

Lower viscosity Signup and view all the answers

What is the role of diploidy in eukaryotic reproduction?

It facilitates the oscillation between haploid and diploid phases. Signup and view all the answers

Which neurotoxin inhibits the release of acetylcholine (ACh) from neuron terminals?

Botulinum toxin Signup and view all the answers

What is a significant outcome of recombination during meiosis?

It leads to increased genetic variability. Signup and view all the answers

Which of the following describes homologous chromosomes?

They are arranged in the same order but may have different alleles. Signup and view all the answers

What is a disadvantage of genetic variability?

It may result in genetic disorders. Signup and view all the answers

How does Sarin nerve gas affect neurotransmission?

It prevents the degradation of acetylcholine in the synaptic space. Signup and view all the answers

What advantage does diploidy provide during meiosis?

It allows for the creation of gametes with unique genetic combinations. Signup and view all the answers

What is the primary characteristic of the pufferfish neurotoxin?

It blocks the opening of voltage-gated sodium channels. Signup and view all the answers

Study Notes

Lab 1: Writing a Scientific Report

Hybridization first recorded between green sea turtles (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) in Southeast Pacific.
Overlapping habitats and population size disparity may contribute to hybridization.
Evidence includes morphological characteristics and lineage identification of hybrid sample found in El Ñuro.
Importance of clear communication of findings for replication and documentation purposes.
Establishing hypotheses aids in guiding experiments.

Lab 2: Transport of Substances Across the Cell Membrane

Key factors influencing molecular movement across cell membranes: molecular weight, concentration gradient, temperature, viscosity, solubility, surface area, and agitation.
Diffusion in Water: Potassium permanganate diffused faster in distilled water due to fewer impurities.
Diffusion in Colloid: Methylene blue exhibited the greatest diffusion due to lower viscosity compared to potassium permanganate and congo red.
Dialysis Experiment: Chloride ions diffused faster than calcium ions through a semi-permeable membrane made with longganisa skin.
Osmosis: Water movement across a semipermeable membrane from low to high solute concentration; observed weight increase in yeast solution.
Osmosis in Red Blood Cells: Changes in cell diameter observed in response to different NaCl concentrations (hypotonic, isotonic, hypertonic).

Quick General Notes on Cell Transport

Cell Membrane Composition: Phospholipid bilayer with hydrophilic heads and hydrophobic tails; integral and peripheral proteins contributing to transport and signaling.
Passive Transport: Does not require energy; includes simple diffusion and facilitated diffusion through proteins.
Active Transport: Requires energy (ATP); involves moving molecules against the concentration gradient, utilizing primary and secondary transport mechanisms.
Bulk Transport: Includes endocytosis and exocytosis for large molecules; receptor-mediated endocytosis selectively internalizes substances.

Lab 3: Action Potential (Inhibitory and Excitatory Responses)

Neuron resting potential is approximately -70mV, maintained by sodium-potassium pump.
Graded potentials are generated by neurotransmitters’ stimulation from connected neurons, leading to action potentials if the threshold of -55mV is reached.
Neurotoxins like botulinum toxin and sarin interfere with neurotransmitter function, blocking sodium channels or preventing acetylcholine breakdown, affecting neural transmission.

Lab 4: Diploidy and Genetic Variability

Diploidy: Condition with two sets of chromosomes; key factor in eukaryotic evolution and bisexual reproduction.
Homologous Chromosomes: Pairs in diploid cells that facilitate genetic recombination during meiosis, creating unique gametes.
Genetic Variability: Positive aspects include adaptation and evolutionary diversity; negative aspects can include genetic disorders and diseases.

Studying That Suits You

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

Description

This quiz focuses on the critical elements of writing a scientific report, specifically regarding the hybridization of Chelonia mydas and Eretmochelys imbricata sea turtles. You'll evaluate aspects such as problem statements, hypothesis formulation, and discussion alignment. Test your understanding of scientific reporting standards and clarity.