Biology Unit 1: Diversity of Living Things

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Questions and Answers

Which process results in daughter cells with half the number of chromosomes as the parent cell?

Karyotype

Meiosis (correct)

Synapsis

Mitosis

What is the name of the structure formed when homologous chromosomes pair up during Prophase I?

Centromere

Tetrad (correct)

Chromatid

Spindle Fiber

What is the term used to describe an individual's complete set of chromosomes?

Homologous Pair

Phenotype

Karyotype (correct)

Genotype

Which chromosomal abnormality is characterized by having three homologous chromosomes in place of a homologous pair?

Down syndrome Signup and view all the answers

What is the significance of the antiparallel arrangement of DNA strands?

It is crucial for DNA replication Signup and view all the answers

Given the original DNA sequence -TAAGGCATTT-, which of the following represents an insertion mutation?

-TAACG CATTTT- Signup and view all the answers

In a co-dominant species, what would be the phenotype of a heterozygote?

A phenotype blending both alleles Signup and view all the answers

According to the provided genetic information, which of the following genotypes would result in a female with hemophilia?

XhXh Signup and view all the answers

What process involves the exchange of chromosome segments between homologous pairs?

Crossing over Signup and view all the answers

If a male child is born with hemophilia, what is the source of the hemophilia allele?

The Mother's X chromosome Signup and view all the answers

In the context of cystic fibrosis inheritance, what genotype will result in an individual who is a carrier, but does not have the condition?

Cc Signup and view all the answers

Which of the following best describes the primary function of carbohydrates within the human body based on the information provided?

Fuel the brain, kidneys, heart, muscles and central nervous system Signup and view all the answers

Which of the following represents a structural component of proteins?

Amino acids Signup and view all the answers

In the digestive system, what is the role of the hormone gastrin?

It tells the cells in the stomach to release gastric juice. Signup and view all the answers

What is the primary function of bile?

Break down large lipid droplets into smaller micelles. Signup and view all the answers

Which substance produced by the pancreas neutralizes the acidity of chyme in the small intestine?

Bicarbonate ions Signup and view all the answers

What is the primary cause of low genetic variation in cheetah populations?

A founder effect event involving a small number of individuals. Signup and view all the answers

Which of these is the main function of xylem tissue in plants?

Transporting water and dissolved nutrients upward from the roots. Signup and view all the answers

What is the function of the cell wall in plant cells?

Providing strong and upright structure. Signup and view all the answers

What process is described when pollen from a flower fertilizes another flower on the same plant?

Self-pollination. Signup and view all the answers

What is the role of phloem tissue in plants?

Transporting food from leaves to other parts of the plant. Signup and view all the answers

What are the main products of photosynthesis?

Glucose and oxygen. Signup and view all the answers

What is the primary function of a pollen tube?

To deliver male gametes to the female gametophyte. Signup and view all the answers

Which of these is an example of asexual reproduction in plants?

Vegetative propagation from roots or stems. Signup and view all the answers

Which concept, as outlined in the text, is NOT a driving force of natural selection?

Artificial selection Signup and view all the answers

How does artificial selection differ from natural selection, as described in the text?

Artificial selection is driven by human-selected traits, while natural selection is driven by the environment. Signup and view all the answers

What is the primary reason for the disappearance of harmful mutations in a population?

Reduced reproductive success of organisms with the mutation Signup and view all the answers

What did Darwin observe about the fossils he found?

They were often similar to present-day species living in the same region. Signup and view all the answers

What is the main flaw in Lamarck's theory of evolution, as described in the text?

The theory suggests that acquired traits during an organism's life are passed onto its offspring. Signup and view all the answers

Which of the following is a direct consequence of Charles Lyell's uniformitarianism?

The concept that Earth required millions of years to accumulate geological changes Signup and view all the answers

What is a key characteristic of the flightless cormorant found by Darwin?

It is the only cormorant that has completely lost the ability to fly. Signup and view all the answers

What is the primary effect of stabilizing selection on a population?

It favors an intermediate phenotype and reduces variation. Signup and view all the answers

Homologous structures provide strong evidence for which evolutionary concept?

Common ancestry among diverse species Signup and view all the answers

How does directional selection influence the distribution of phenotypes in a population?

It shifts the distribution curve in one direction, favoring one extreme. Signup and view all the answers

Vestigial features are best described as:

Structures with no known function, often resembling functional structures in related species Signup and view all the answers

What evidence, contrary to Darwin's theory of evolution, would falsify his theory according to the text?

Fossils layered in no particular sequence with no homologous or vestigial features Signup and view all the answers

What outcome is typically observed with disruptive selection?

A population with two distinct extreme phenotypes and eliminates intermediate phenotypes. Signup and view all the answers

Which of the following is a defining factor of genetic drift?

Changes in allele frequencies due to chance events in small populations Signup and view all the answers

What is a characteristic outcome of a genetic bottleneck?

Significant loss of genetic variation and an increase in genetic drift Signup and view all the answers

The development of the elephant trunk or lobster claws are examples of:

Selective pressures that aid in survival and reproduction Signup and view all the answers

What is the primary function of the septum within the heart?

To prevent the mixing of oxygenated and deoxygenated blood. Signup and view all the answers

How does the presence or absence of a septum affect the type of circulation in an organism?

A septum leads to complete circulation due to separate blood flow, while lack of septum results in mixed blood flow or incomplete circulation. Signup and view all the answers

Why do mammals require complete circulation with the blood kept separate in four chambers, in contrast to amphibians?

Mammals need complete circulation due to their higher metabolism and need for efficient oxygen delivery to cells. Signup and view all the answers

What is the primary function of arteries in the circulatory system?

To carry blood away from the heart with high pressure. Signup and view all the answers

Which type of blood vessel is characterized by having thin walls and valves to prevent backflow?

Veins Signup and view all the answers

What feature allows capillaries to function as the site of nutrient and waste exchange?

One cell thick walls Signup and view all the answers

What is the relationship between the lumen size and the function of veins compared to arteries?

Veins have a wider lumen to decrease friction and ease blood flow, compared to arteries. Signup and view all the answers

Which statement best describes the relationship between the wall thickness and function of arteries?

Arteries have thick, elastic walls to withstand the high pressure from the heart and to recoil to push blood along. Signup and view all the answers

Study Notes

Unit 1: Diversity of Living Things

Biological species concept: Individuals are considered the same species if they breed naturally and produce fertile offspring.
Morphological species concept: Individuals are considered the same species if they share similar physical characteristics (morphology).
Genetic diversity is important for species survival as it enables adaptation to environmental changes.
Species diversity is the variety of species within an ecosystem, which is higher in warmer, wetter climates.
Structural diversity refers to the variety of shapes and sizes of organisms within an ecosystem.
Ecosystem diversity is the variety of ecosystems on Earth.
Taxonomy is the traditional classification system of organisms based on shared physical characteristics, with 7 levels: Kingdom, Phylum, Class, Order, Family, Genus, Species (KPCOFGS).
Scientific name: Binomial nomenclature uses two words to name species: genus and species (e.g., Homo sapiens). The genus name is capitalized.

Cell Types

Bacteria: Prokaryotic, unicellular, cell wall made of peptidoglycan; important in nutrient recycling and nitrogen fixation.
Protists: Eukaryotic, unicellular or multicellular, some have cellulose cell walls. Important primary producers in aquatic ecosystems.
Fungi: Eukaryotic, mostly multicellular, cell wall of chitin. They are decomposers and participate in nutrient cycling and symbiotic relationships with plants.
Plants: Eukaryotic, multicellular, cell wall of cellulose. Important producers of oxygen and food, supporting ecosystems.

Other Key Concepts

Domains are the highest taxonomic unit, with three domains: Eubacteria, Archaea, and Eukarya.
Dichotomous keys are used to identify organisms by branching two-part statements.
Phylogeny demonstrates evolutionary relationships between groups, based on shared ancestry.
Paramecium: unicellular organism with contractile vacuoles, a gullet, cilia, and trichocysts.
Euglena: unicellular organism with a contractile vacuole, mitochondria, an eye spot, and a flagellum.

Bacteria structure and reproduction.

Plasmids: smaller loops of DNA with genes that provide a survival advantage (e.g., antibiotic resistance).
Flagella: protein propellers for movement.
Pilus: stiff proteins assisting in cell-to-cell attachment.
Endospores: protective structures created under stress to preserve the bacteria.
Capsules: sticky protective layers assisting bacterial attachment.
Binary Fission: asexual reproduction where a cell divides into two genetically identical daughter cells.
Conjugation: genetic exchange between cells.
Transformation: intake of DNA from dead cells.

Viruses

Lytic cycle: viral reproduction resulting in the bursting of a host cell releasing new viruses.
Lysogenic cycle: viral reproduction involving the integration of viral DNA into the host DNA leading to dormant periods.

Animal Classification

Bilateral symmetry: body can be divided into right and left halves along a central plane.
Radial symmetry: body parts repeat around a central axis.

Asexual vs. Sexual Reproduction

Asexual reproduction involves a single parent producing identical offspring, like binary fission or budding.
Sexual reproduction involves two parents creating genetically diverse offspring through the fusion of gametes.

Regulation of body temperature

Endotherms: warm blooded animals that maintain a constant body temperature using internally generated heat.
Ectotherms: cold-blooded animals that regulate their body temperature mainly by exchanging heat with their environment.

Human Physiology (Digestive and Respiratory Systems)

The digestive system involves mouth, esophagus, stomach, small intestine, liver, pancreas, gallbladder, large intestine and rectum.
The respiratory system involves trachea, bronchi, bronchioles, alveoli.

Mitosis and Meiosis

Mitosis results in two genetically identical daughter cells; it allows for growth and repair.
Meiosis results in four genetically unique daughter cells with half the number of chromosomes; essential in sexual reproduction.

Cell Division Stages

Interphase, prophase, metaphase, anaphase, telophase, cytokinesis.
Synapsis: homologous chromosomes' pairing to form tetrad formation during meiosis.
Crossing over: exchange of genetic material between homologous chromosomes.

Evolutionary Concepts

Natural Selection: organisms with advantageous traits are more likely to survive and reproduce, leading to adaptation.
Artificial Selection: Humans choose desired traits in organisms to breed and create new varieties (e.g., dog breeds).
Genetic Variation: Differences in traits among individuals due to genes.
Catastrophism (Cuvier): Earth's geological features resulted from sudden, great events.
Uniformitarianism (Lyell): Geologic processes have been uniform throughout Earth's history.

Adaptations

Homologous structures share a common evolutionary origin.
Analogous structures have similar functions but don't share a common evolutionary origin.
Vestigial structures are remnants of structures that were functional in ancestral organisms.

Other concepts

Karotype: display of an organism's chromosomes.
Mutation: change in genetic code that results in alterations to an organism's traits.
Genetic drift: change in allele frequencies due to chance in small populations.

Unit 3: Genetics.

Unit 4: Evolution.

Unit 5: Plants.

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Description

Explore the fascinating world of biodiversity in this quiz. Learn about the biological species concept, morphological characteristics, and the importance of genetic, species, structural, and ecosystem diversity. Test your knowledge on taxonomy and binomial nomenclature.