Supplementing and Detailing Biological Knowledge

1. Which of the following cells creates the surface of contact between the plant root and the soil?

Root hair cells: These are epidermal cells of the root, elongated and thin with a thin cell wall, no chloroplasts and numerous hairs. The main function of root hairs is to absorb water and mineral ions from the soil.

* Root hairs only appear in the root tip, where the ability to absorb water and minerals is present.
* Root hairs increase the surface area of contact between the plant root and soil, helping the plant absorb water and minerals more effectively.

2. In a community, what is the relationship between starlings and buffalo?

Mutualism: Mutualism is a relationship between two species where both benefit. Starlings often perch on the backs of buffalo to catch parasites like ticks and fleas. The starlings get food, while the buffalo are relieved of parasites.

* Mutualism is a type of symbiosis, but it is not obligatory. This means both species can survive independently without the other.
* Besides starlings and buffalo, there are many other examples of mutualism in nature, such as cleaner fish and sharks, and woodpeckers and giraffes.

3. In an animal cell, where is the following location where genes are often not evenly distributed during cell division?

In mitochondria: Mitochondria are organelles responsible for respiration, containing their own DNA and having a genetic mechanism independent of nuclear DNA. During cell division, mitochondrial division is often uneven, leading to uneven distribution of genes in mitochondria among daughter cells.

* Mitochondrial DNA is maternally inherited.
* Genes in mitochondria are usually related to mitochondrial functions, such as cellular respiration.

4. Morgan discovered linked gene inheritance, crossing over, and sex-linked inheritance. His experiment was based on fruit flies.

Morgan used fruit flies to study the laws of inheritance. He discovered linked gene inheritance, crossing over, and sex-linked inheritance.
Morgan’s experiment demonstrated that genes are located on chromosomes and that genes located on the same chromosome tend to be inherited together.

* Fruit flies are a model organism widely used in genetics research due to their short reproductive cycle, high number of offspring, and ease of breeding.
* Morgan’s research laid the foundation for the development of modern genetics.

5. Correns discovered extranuclear inheritance.

Correns was the first scientist to demonstrate extranuclear inheritance. He used yeast for his research and discovered that some traits were inherited by factors outside the cell nucleus.

* Extranuclear inheritance is the inheritance of traits determined by genes located on the DNA of organelles like mitochondria and chloroplasts.
* Extranuclear inheritance is often referred to as cytoplasmic inheritance, as genes in the cytoplasm are capable of independent inheritance from nuclear genes.

6. Natural selection strengthens the adaptability of traits by accumulating advantageous alleles.

Natural selection is the process of screening individuals with genotypes that are better adapted to the environment. These individuals survive, reproduce, and pass their genes on to the next generation. Over many generations, the frequency of beneficial alleles increases in the population, leading to increased adaptability of the population.

* Natural selection is a major evolutionary force that helps species adapt to their living environment.
* Natural selection is not a perfect process and can be influenced by factors such as climate change and environmental changes.

7. Natural Selection is the MAIN factor shaping the populations of organisms to adapt to the environment.

Natural selection plays a primary role in shaping evolution and adaptation of organisms. It selects individuals with genotypes more suitable for the environment, helping the population adapt to changing living conditions.

* Natural selection is an active evolutionary force that constantly acts on populations of organisms.
* Other evolutionary forces include mutations, gene flow, and non-random mating.

8. The number of pure lines = the number of gametes (12, topic 1)

The number of pure lines equals the number of gametes only when the organism is homozygous, meaning all its genes are in a homozygous state.
For example, AAbbDd has 2 types of gametes for D, meaning that at the D locus, there are two homozygous alleles (DD or dd).

* The number of pure lines is determined by the number of different alleles of a gene in an organism.
* The higher the number of pure lines, the greater the potential to generate diverse phenotypes.

9. Which of the following factors creates primary material in evolution?

Mutation: Mutation is a change in DNA structure, creating new variations. These variations are the primary raw material for evolution.

* Mutation is a random event and can be harmful, beneficial, or neutral.
* Mutation plays an important role in generating genetic diversity, the basis for evolution.

10. In which era did gymnosperms appear?

Paleozoic Era: Gymnosperms are the group of plants that appeared earliest in the evolutionary history of seed plants. They appeared at the end of the Paleozoic Era (Permian period), approximately 299 – 251 million years ago.

* The Paleozoic Era is an era in Earth’s history, lasting from 541 million years ago to 251 million years ago.
* The Paleozoic Era is divided into six periods: Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian.

11. In the ecosystem, which of the following groups belongs to the group of producer organisms?

Plants (algae): Producer organisms are autotrophs, capable of synthesizing organic matter from inorganic matter by absorbing sunlight energy. In the ecosystem, plants and algae play the role of primary producers.

* Producer organisms are the first trophic level in the food chain.
* Producer organisms provide energy for all other organisms in the ecosystem.

12. How many cases can lead to increased blood pressure?

There are many factors that can lead to increased blood pressure, including:

Lifting heavy objects: Increases resistance for the heart to pump blood.
Anxiety and worry: Increased adrenaline hormone secretion, leading to faster heart rate and higher blood pressure.
Faster heart rate than normal: Increased blood pumped out of the heart, leading to higher blood pressure.
Arterial hardening: Reduced elasticity of blood vessels, increasing resistance to blood flow, leading to higher blood pressure.

* Blood pressure is the pressure of blood on the walls of blood vessels.
* High blood pressure is a dangerous disease that can lead to many other diseases, such as cardiovascular disease and stroke.

13. Which type of cell regulates the transpiration process of plants?

Guard cells: Stomata are small pores on the surface of leaves, surrounded by two guard cells. Guard cells are capable of regulating the opening and closing of stomata, thereby regulating the transpiration process of plants.

* Transpiration is the process of water evaporating from the leaves of plants into the environment.
* Transpiration plays a crucial role in the transport of water and minerals in plants, regulating temperature for the plant.

14. How can plant roots absorb water?

Osmosis: Osmosis is the phenomenon of water moving from an area of high water concentration (low solute concentration) to an area of low water concentration (high solute concentration) through a semipermeable membrane.

* Plant roots absorb water from the soil due to the difference in water concentration between the soil and root cells.
* The water concentration in root cells is usually lower than the water concentration in the soil, so water will move into the root cells by osmosis.

15. Transpiration is the process that creates the upward pull of the xylem stream.

Transpiration from plant leaves creates a pull from top to bottom, pulling water from the roots upwards through the xylem. This pull is called the upward pull of the xylem stream.

* The downward pull of the xylem stream is root pressure, which is caused by the movement of water from the soil into the roots.
* The xylem stream is the flow of water from the roots to the leaves, supplying water and minerals to the plant.

16. The universality of the genetic code provides evidence for the common origin of life.

The genetic code is a system of encoding genetic information used by all living organisms. The universality of the genetic code (except for a few minor exceptions) suggests that all living organisms have a common origin from a common ancestor.

* The genetic code consists of 64 codons that encode 20 amino acids.
* The universality of the genetic code is strong evidence for the theory of evolution.

17. Which type of mutation does not alter the number of chromosomes in a cell?

Structural chromosome mutations do not alter the number of chromosomes, including:

Inversion: A segment of the chromosome is reversed 180 degrees.
Duplication: A segment of the chromosome is duplicated.
Deletion: A segment of the chromosome is lost.

* Structural chromosome mutations can cause many genetic diseases.
* Other types of mutations that alter the number of chromosomes include: triploidy, tetraploidy, monosomy.

18. Where is the gene located that determines the trait inherited from the mother?

When a gene is located on the cytoplasm (mitochondria, chloroplasts), the trait is inherited from the mother.

* The cytoplasm is transmitted from mother to offspring.
* Genes in mitochondria and chloroplasts are often associated with traits such as flower color and disease resistance.

19. Which line of plants does the method of creating plant varieties using odd polyploidy mutations not apply to?

The method of creating plant varieties using odd polyploidy mutations does not apply to seed-bearing plant lines. This is because odd polyploids do not reproduce sexually, meaning they produce seedless fruits.

* Odd polyploids are often used for root, fruit, and leaf crops.
* Odd polyploids can make crops larger and more productive.

20. Gene mutations create primary genetic variation.

Crossbreeding creates secondary genetic variation.
Gene mutations are the primary raw material of evolution. Crossbreeding causes these mutations to be recombined, creating many new genotypes, which is secondary genetic variation.

* Crossbreeding is an important evolutionary factor, helping populations have diverse genotypes.
* Crossbreeding can be random or non-random.

21. Basic characteristics of producer organisms:

Always classified as the first trophic level.
Ability to photosynthesize and synthesize organic matter.
Often have the largest total biomass.
Transfer energy from the environment into the community through photosynthesis.

* Producer organisms are the foundation of the ecosystem.
* Energy is transferred from producer organisms to higher trophic levels in the food chain.

22. Of the types of photosynthetic pigments, only chlorophyll a has the ability to convert light energy into ATP energy.

Chlorophyll a is the main pigment in photosynthesis, absorbing light energy to carry out the photochemical reaction.

* Chlorophyll b and other pigments like carotenoids and xanthophylls function to absorb supplementary light and transfer energy to chlorophyll a.
* ATP is a molecule that provides energy for biochemical reactions in the cell.

23. There are many types of light rays, but photosynthesis mainly uses two types?

Red light and blue-violet light: Photosynthesis primarily uses two types of light rays: red light and blue-violet light.

* Red light has a longer wavelength than blue-violet light.
* Red light stimulates glucide synthesis, while blue-violet light stimulates the synthesis of proteins and amino acids.

24. Plants are divided into two types:

Sun-loving plants and shade-tolerant plants: Sun-loving plants are those that grow well in areas with high light intensity, while shade-tolerant plants grow well in areas with low light intensity.

* Sun-loving plants usually have small, thick leaves with multiple epidermal layers.
* Shade-tolerant plants usually have large, thin leaves with fewer epidermal layers.

25. People who constantly lack the following substance may develop night blindness?

Vitamin A: Vitamin A is a fat-soluble vitamin that is essential for vision. Lack of vitamin A can lead to night blindness (difficulty seeing in low light conditions).

* Vitamin A is abundant in animal liver, eggs, milk, and green vegetables.
* Night blindness can be cured by supplementing with vitamin A.

26. A person with heart disease needs to have a pacemaker installed. Which part of the heart has failed in this person?

Sinoatrial node: The sinoatrial node is the center of the heart’s rhythm that stimulates heart activity. When the sinoatrial node fails, the heart cannot generate its own rhythm normally, leading to arrhythmia, requiring a pacemaker to regulate the heartbeat.

* A pacemaker is a medical device used to treat arrhythmias.
* A pacemaker works by emitting electrical impulses to stimulate the heart to contract rhythmically.

27. Translation is the process of synthesizing polypeptide chains through peptide bonds.

Translation is the process of protein synthesis, which occurs in the ribosome organelle.

* A polypeptide chain is a chain of amino acids linked together by peptide bonds.
* Translation uses the genetic information encoded on mRNA to synthesize protein.

28. mRNA, tRNA, rRNA:

mRNA (messenger RNA): Carries genetic information from DNA in the cell nucleus to ribosomes.
tRNA (transfer RNA): Transfers amino acids to ribosomes for protein synthesis.
rRNA (ribosomal RNA): Makes up ribosomes, where translation occurs.

* mRNA, tRNA, and rRNA are the three main types of RNA involved in protein synthesis.

29. Birds rely on light to navigate their direction when traveling from the northern to the southern hemisphere.

Birds are capable of navigating using various factors such as the position of the sun, stars, and Earth’s magnetic field.

* Birds’ navigational ability is one of nature’s wonders.
* Bird migration is an inherited behavior that helps them find food and suitable breeding grounds.

30. When blood sugar levels rise (hyperglycemia), the body secretes more insulin.

When blood sugar levels decrease, the pancreas secretes glucagon.
Insulin is a hormone secreted by the pancreas, which lowers blood sugar by promoting glucose uptake into cells. When blood sugar levels decrease, the pancreas secretes glucagon, which raises blood sugar by mobilizing glucose stored in the liver.

* Blood sugar levels need to be maintained at a stable level.
* Diabetes is a metabolic disorder characterized by high blood sugar levels.

31. The lungs participate in regulating blood pH by releasing CO2.

CO2 is a byproduct of cellular respiration. When CO2 dissolves in blood, it forms carbonic acid (H2CO3), reducing blood pH. The lungs release CO2, helping to maintain blood pH at a stable level.

* Blood pH is an important indicator of the acid-base balance of the blood.
* Blood pH needs to be maintained within a range of 7.35 to 7.45.

32. Organisms capable of photosynthesis are all classified as producers.

Producers are autotrophic organisms, capable of synthesizing organic matter from inorganic matter. Photosynthesis is a form of autotrophy, so organisms capable of photosynthesis are all classified as producers.

* Producer organisms are the first trophic level in the food chain.

33. Which process creates the DOWNWARD pull of the xylem stream?

Root pressure: Root pressure is the force pushing water from the roots upwards through the plant stem, generated by the difference in water concentration between the soil and root cells. Root pressure plays the role of the downward pull of the xylem stream.

* Root pressure is a weak force that only works under certain conditions.
* The upward pull of the xylem stream is the pull created by transpiration from leaves.

34. Which of the following animals breathes through trachea?

Grasshoppers: Grasshoppers are insects that breathe through a tracheal system. Trachea are small tubes that run throughout the body, helping to deliver oxygen and remove carbon dioxide.

* The tracheal system is an efficient respiratory system that helps insects breathe in dry environments.
* The trachea are connected to spiracles on the insect’s body.

35. Legumes are planted to add nitrogen to the soil.

Legumes have the ability to fix nitrogen from the air thanks to their symbiotic relationship with nitrogen-fixing bacteria. Nitrogen is an essential nutrient for plants, so planting legumes helps to replenish nitrogen in the soil.

* Nitrogen-fixing bacteria live in nodules on the roots of legumes.
* Nitrogen is fixed in the form of ammonia (NH3) which is then absorbed by the plants.

36. Manure and biofertilizers supplement the soil with beneficial microorganisms.

Manure and biofertilizers contain numerous beneficial microorganisms that help improve soil fertility.

* Beneficial microorganisms help decompose organic matter in the soil, forming nutrients for plants.
* Beneficial microorganisms also improve soil structure and increase water retention in the soil.

37. Inorganic nitrogen fertilizers will increase soil acidity (harmful) such as urea fertilizer.

Inorganic nitrogen fertilizers are often acidic, increasing soil acidity when applied.

* Soil acidity affects the ability of plants to grow and develop.
* Applying inorganic nitrogen fertilizers should be combined with soil improvement measures to reduce acidity.

38. Which of the following crosses is commonly used to create hybrid vigor?

Cross-line breeding: Cross-line breeding is the crossing of two different pure lines, resulting in offspring with hybrid vigor (higher reproductive efficiency than parents).

* Hybrid vigor is the phenomenon of offspring having stronger vitality, higher productivity, and better disease resistance than their parents.
* Cross-line breeding is widely used in agricultural production to increase the productivity of crops and livestock.

39. Transcription and translation are the processes of synthesizing which types of molecules?

Transcription: Synthesizing RNA from DNA.
Translation: Synthesizing proteins from RNA.

* Transcription occurs in the cell nucleus, translation occurs in the ribosome organelle.
* These two processes are the basis for the expression of genetic information.

40. The actual lifespan of an individual is called?

Ecological age: Ecological age is the actual lifespan of an individual in nature, influenced by environmental factors such as food, disease, and predators.

* Ecological age is usually shorter than physiological age.

41. The maximum lifespan of an individual?

Physiological age: Physiological age is the maximum lifespan of an individual under the most favorable conditions, not affected by environmental factors.

* Physiological age is the living potential of a species.

42. The average age of individuals in a population of organisms?

Population age: Population age is the average age of individuals in a population, calculated by summing the ages of all individuals and dividing by the number of individuals.

* Population age is an indicator of the age structure of the population.
* The age structure of a population affects the reproductive capacity and development of the population.

In addition to the information above, you should pay attention to a few points:

Consult additional reference materials: To better understand biological knowledge, you should consult specialized materials such as textbooks, reference books, and scientific articles.
Contact teachers: If you have any questions, contact your teacher for clarification.
Practice: Practicing experiments and observing natural phenomena will help you understand biological knowledge better.
Combine learning with fun: Learning biology can be more enjoyable when you combine learning with fun, such as joining science clubs and visiting natural museums.

Good luck with your studies!

Supplementing and Detailing Biological Knowledge