Biology: Life Forms and Features
102 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary role of the plasma membrane in cellular organization?

  • To separate the cell from its external environment (correct)
  • To facilitate cellular respiration
  • To synthesize proteins
  • To enable cell division

Why are lipids particularly suitable for forming the plasma membrane?

  • They provide energy for cellular processes
  • They contain nucleic acids that stabilize membranes
  • They have both hydrophobic and hydrophilic properties (correct)
  • They are soluble in water and can transport molecules

What component of phospholipids is hydrophilic?

  • Fatty acid tails
  • Carbon-hydrogen chains
  • Hydrophobic regions
  • Phosphate head (correct)

What characteristic of lipids contributes to their role in maintaining the structure of the plasma membrane?

<p>Their hydrophobic nature and insolubility in water (D)</p> Signup and view all the answers

In a cellular context, what does the term 'amphipathic' refer to?

<p>Molecules that can be soluble in both polar and non-polar environments (C)</p> Signup and view all the answers

Which process allows DNA to serve as genetic material in cellular life?

<p>Replication of DNA (D)</p> Signup and view all the answers

What distinguishes eukaryotic cells from prokaryotic cells?

<p>Presence of a true nucleus (A)</p> Signup and view all the answers

What is the primary function of RNA in the central dogma of molecular biology?

<p>It transports genetic instructions. (C)</p> Signup and view all the answers

What role do ribosomal RNA (rRNA) play in the cell?

<p>Form the core of ribosome structure for protein synthesis (A)</p> Signup and view all the answers

What is a significant characteristic of the cytoplasm in cellular life?

<p>It is a site of metabolic activity and contains organelles. (D)</p> Signup and view all the answers

How does the cell membrane differ between prokaryotic and eukaryotic cells?

<p>Eukaryotic cells have a fluidic shape without a cell wall. (A)</p> Signup and view all the answers

What aspect of cellular evolution is indicated by the presence of a nucleus?

<p>Compartmentalization leading to functional diversity. (B)</p> Signup and view all the answers

What is a common feature of both prokaryotic and eukaryotic cells?

<p>Contain ribosomes (A)</p> Signup and view all the answers

In the context of the 3 Domain System, what is a characteristic of Archaea?

<p>Distinct rRNA sequences differing from Eubacteria. (D)</p> Signup and view all the answers

What is the primary function of the hydrophobic tails in the phospholipid bilayer?

<p>To prevent mixing with external substances (A)</p> Signup and view all the answers

Which of the following correctly describes prokaryotic cells?

<p>Possess a defined nuclear region called the nucleoid (D)</p> Signup and view all the answers

What distinguishes Gram-negative bacteria from Gram-positive bacteria?

<p>Gram-negative bacteria possess an outer membrane with lipoproteins (C)</p> Signup and view all the answers

Which of the following statements about mitochondria is accurate?

<p>They contain their own DNA and ribosomes intermediate to other organelles (B)</p> Signup and view all the answers

What structural feature of plant cells provides stability and protection?

<p>Cellulose cell wall (B)</p> Signup and view all the answers

Which cellular structure is involved in the breakdown of glucose in the mitochondrial matrix?

<p>Cristae (A)</p> Signup and view all the answers

Which of the following statements regarding eukaryotic cells is incorrect?

<p>They are smaller than prokaryotic cells on average (B)</p> Signup and view all the answers

What is the function of polysaccharide capsules in some bacteria?

<p>To enhance survival in harsh conditions (B)</p> Signup and view all the answers

What cellular characteristic is common to both mitochondria and chloroplasts?

<p>Contain their own ribosomes and DNA (D)</p> Signup and view all the answers

What is the primary purpose of crossover during meiosis?

<p>To increase genetic variation. (A)</p> Signup and view all the answers

Which statement accurately describes the differences between prokaryotic and eukaryotic cells?

<p>Only eukaryotic cells have a defined nucleus (B)</p> Signup and view all the answers

What happens during Meiosis I?

<p>Homologous chromosomes separate into haploid cells. (B)</p> Signup and view all the answers

Which process describes the separation of sister chromatids in meiosis?

<p>Anaphase II. (A)</p> Signup and view all the answers

What characterizes the diploid cell at the start of meiosis?

<p>It contains two copies of each chromosome. (D)</p> Signup and view all the answers

How does random fertilization contribute to genetic variation?

<p>By combining different gametes from two parents. (B)</p> Signup and view all the answers

What is the primary event that occurs during the Anaphase stage of Mitosis?

<p>Sister chromatids are separated (B)</p> Signup and view all the answers

Which phase of the cell cycle is characterized by the synthesis of DNA?

<p>S phase (C)</p> Signup and view all the answers

During which stage does the nuclear envelope start to re-form?

<p>Telophase (D)</p> Signup and view all the answers

What essential cellular process is linked to the frequency of mitosis?

<p>Growth and metabolism (C)</p> Signup and view all the answers

Which structure is crucial for the alignment of chromosomes during Metaphase?

<p>Kinetochore microtubules (A)</p> Signup and view all the answers

What occurs during cytokinesis in M-phase?

<p>Division of the cytoplasm (D)</p> Signup and view all the answers

In which phase are nonkinetochore microtubules significantly involved?

<p>Metaphase (C)</p> Signup and view all the answers

What is a key characteristic of Interphase?

<p>Preparation for mitosis (C)</p> Signup and view all the answers

What structural feature is prominent during the Prophase stage?

<p>Nuclear envelope dissolution (A)</p> Signup and view all the answers

What happens to the centrosomes during G2 phase of Interphase?

<p>They replicate to form two centrosomes. (D)</p> Signup and view all the answers

What is the central process involved in all types of cell division?

<p>DNA replication (C)</p> Signup and view all the answers

Which eukaryotic cell division process involves the dissolution and reformation of the nuclear envelope?

<p>Mitosis (A)</p> Signup and view all the answers

What is the role of the centrosome during mitosis?

<p>Anchoring the mitotic spindle (B)</p> Signup and view all the answers

Which of the following statements accurately describes binary fission?

<p>It is a process where a parent cell divides into two identical daughter cells. (A)</p> Signup and view all the answers

During which stage of cell division does cytokinesis primarily occur?

<p>Telophase (D)</p> Signup and view all the answers

How do different types of cells organize their DNA for cell division?

<p>According to their specific structural requirements (C)</p> Signup and view all the answers

What occurs following the separation of sister chromatids during cell division?

<p>Division of the cytoplasm (B)</p> Signup and view all the answers

Which statement is true about prokaryotic and eukaryotic cell division differences?

<p>Eukaryotic cells have a defined nucleus and may undergo mitosis. (C)</p> Signup and view all the answers

Which structure is formed by microtubules during the mitosis process?

<p>Mitotic spindle (C)</p> Signup and view all the answers

What is a critical feature of the mitotic spindle in ensuring equal chromosomal content in daughter cells?

<p>Polarity of the microtubules (D)</p> Signup and view all the answers

What is a primary function of the Golgi apparatus?

<p>Sorting and directing intracellular traffic (C)</p> Signup and view all the answers

Which of the following correctly describes the function of lysosomes?

<p>They degrade macromolecules and recycle organelles (B)</p> Signup and view all the answers

How do vesicles originating from the rough endoplasmic reticulum reach the Golgi apparatus?

<p>By budding off and transporting their protein cargo (D)</p> Signup and view all the answers

What is the role of the smooth endoplasmic reticulum in relation to the Golgi apparatus?

<p>It traffics lipids including steroid hormones to the Golgi (C)</p> Signup and view all the answers

Which statement best describes the 'cis' and 'trans' faces of the Golgi apparatus?

<p>The cis face receives vesicles from the ER, while the trans face ships vesicles to the plasma membrane. (D)</p> Signup and view all the answers

In what way do lysosomes contribute to cellular response to pathogens?

<p>By facilitating the process of phagocytosis (B)</p> Signup and view all the answers

What is a characteristic feature of the digestive enzymes found in lysosomes?

<p>They are produced in the rough endoplasmic reticulum and activated in the lysosome. (D)</p> Signup and view all the answers

What distinguishes exocytosis from endocytosis in cellular transport processes?

<p>Endocytosis captures external materials, while exocytosis releases materials from the cell. (A)</p> Signup and view all the answers

How do fungal hyphae increase their efficiency in overcoming the surface area: volume ratio problem?

<p>By elongating and branching to increase surface area. (C)</p> Signup and view all the answers

What structural adaptation in eukaryotic muscle tissue helps to mitigate the surface area: volume ratio issue?

<p>Muscle cells form thin, elongated fibers. (A)</p> Signup and view all the answers

Which characteristic of plant cells aids in addressing the surface area: volume ratio challenge?

<p>Presence of specialized root hairs to maximize surface area. (B)</p> Signup and view all the answers

What role do nuclear pores play in the function of the nuclear envelope?

<p>They regulate the transport of molecules in and out of the nucleus. (A)</p> Signup and view all the answers

How does the structure of chromatin contribute to DNA functionality?

<p>By providing a dynamic structure that enables access to specific genes. (C)</p> Signup and view all the answers

What feature of the nuclear lamina is crucial for the function of the nucleus?

<p>It reinforces the nuclear envelope and maintains its shape. (C)</p> Signup and view all the answers

What is the significance of the double helix structure of DNA?

<p>It supports both replication and transcription processes through its unique configuration. (D)</p> Signup and view all the answers

Which of the following best describes the function of histone proteins in Eukaryotic cells?

<p>They package DNA into nucleosomes, regulating access to genetic information. (C)</p> Signup and view all the answers

What is a significant event that occurs during the Anaphase stage of mitosis?

<p>Separation of sister chromatids. (A)</p> Signup and view all the answers

Which phase of the cell cycle is associated with the synthesis of new DNA?

<p>S phase. (C)</p> Signup and view all the answers

What significant structural feature is formed during Metaphase?

<p>Chromosomes align at the metaphase plate. (A)</p> Signup and view all the answers

What occurs during Telophase in the cell division process?

<p>Nuclear envelopes reform around two sets of chromosomes. (C)</p> Signup and view all the answers

During which phase are centrioles particularly important for the formation of bipolar spindle fibers?

<p>Prophase. (B)</p> Signup and view all the answers

What is the purpose of nonkinetochore microtubules during mitosis?

<p>To anchor the spindle poles. (C)</p> Signup and view all the answers

Which event signifies the transition from Prophase to Prometaphase?

<p>Dissolution of the nuclear envelope. (B)</p> Signup and view all the answers

What characterizes the G1 phase of Interphase?

<p>Cell growth and organelle duplication. (A)</p> Signup and view all the answers

Which process is directly associated with cytokinesis during telophase?

<p>Cleavage furrow formation. (D)</p> Signup and view all the answers

Which checkpoint in the cell cycle is primarily responsible for arresting the cycle if progression signals are not present?

<p>G1 checkpoint (C)</p> Signup and view all the answers

What occurs if a cell does not receive sufficient signals at the G1 checkpoint?

<p>It enters G0 phase (B)</p> Signup and view all the answers

At which point in the cell cycle is DNA replication evaluated for correctness?

<p>G2 checkpoint (A)</p> Signup and view all the answers

What regulates the frequency of mitosis in cells?

<p>Both A and B (C)</p> Signup and view all the answers

What phenomenon occurs when cancer cells escape the normal controls of the cell cycle?

<p>Uncontrolled proliferation (C)</p> Signup and view all the answers

What is the main function of the M checkpoint in the cell cycle?

<p>To verify the correct separation of chromosomes (C)</p> Signup and view all the answers

Which process is linked to the need for cells to undergo apoptosis?

<p>Uncontrolled cell growth (D)</p> Signup and view all the answers

What is a significant outcome of a cell cycle that is not properly regulated?

<p>Formation of tumors (D)</p> Signup and view all the answers

What structural component gives Gram-positive bacteria their characteristic staining?

<p>Major peptidoglycan cell wall (D)</p> Signup and view all the answers

How do plant cells primarily cope with high osmotic pressure?

<p>Through their thick cellulose cell wall (C)</p> Signup and view all the answers

What characteristic is unique to prokaryotes compared to eukaryotes regarding DNA organization?

<p>Nuclear region called nucleoid (C)</p> Signup and view all the answers

Which of the following structures is involved in photosynthesis within plant cells?

<p>Chloroplasts (A)</p> Signup and view all the answers

Which statement about the bacterial cell wall is correct?

<p>It provides extra support and can affect immunogenicity. (C)</p> Signup and view all the answers

What distinguishes the mitochondria of eukaryotic cells from prokaryotic cells?

<p>Double membrane and involvement in cellular respiration (D)</p> Signup and view all the answers

What process allows the separation of eukaryotic metabolic functions into distinct organelles?

<p>Cellular compartmentalization (D)</p> Signup and view all the answers

Which group of bacteria is characterized by having a thicker layer of peptidoglycan, resulting in a positive Gram stain?

<p>Gram-positive bacteria (B)</p> Signup and view all the answers

What is a key structural feature of eukaryotic cell walls, particularly in plants?

<p>Layer of cellulose and middle lamella (A)</p> Signup and view all the answers

What distinguishes the periplasmic space in Gram-negative bacteria?

<p>Location between the outer membrane and thin peptidoglycan layer (A)</p> Signup and view all the answers

What is the primary purpose of DNA replication in relation to cell division?

<p>To ensure accurate duplication and separation of chromosomes. (A)</p> Signup and view all the answers

Which cell type engages in binary fission as its primary method of division?

<p>Bacteria. (C)</p> Signup and view all the answers

In which phase of eukaryotic cell division does the nuclear envelope dissolve?

<p>Prophase. (B)</p> Signup and view all the answers

What structure is primarily responsible for moving chromosomes during mitosis?

<p>Microtubules. (D)</p> Signup and view all the answers

What is a significant outcome of cytokinesis?

<p>Creation of two daughter cells with identical genetic material. (A)</p> Signup and view all the answers

What role does the centrosome play during cell division?

<p>It anchors microtubules and facilitates chromosome movement. (B)</p> Signup and view all the answers

Which cellular structure remains intact during the cell division of most eukaryotes?

<p>The plasma membrane. (D)</p> Signup and view all the answers

What characteristic defines the organization of DNA in bacterial cells?

<p>A single circular chromosome without a nucleus. (A)</p> Signup and view all the answers

What does the term 'polarization' of the mitotic spindle refer to?

<p>The arrangement of microtubule proteins to ensure equal chromosomal content in daughter cells. (D)</p> Signup and view all the answers

Which of the following processes is not associated with mitosis?

<p>Chromosome mutation. (A)</p> Signup and view all the answers

Flashcards

Central Dogma of Molecular Biology

DNA directs RNA production, which in turn directs protein synthesis.

Biomolecules

Large molecules crucial for life, including proteins, carbohydrates, lipids and nucleic acids.

DNA Replication

Process of copying DNA, crucial for cell division.

Transcription

Process where DNA is copied into RNA

Signup and view all the flashcards

Translation

Process where RNA instructions are used to build proteins.

Signup and view all the flashcards

Prokaryotes

Cells lacking a true nucleus and membrane-bound organelles.

Signup and view all the flashcards

Eukaryotes

Cells with a true nucleus and membrane-bound organelles.

Signup and view all the flashcards

Cell Membrane

Outer boundary of a cell, controlling what enters and exits.

Signup and view all the flashcards

Nucleus

The control center of the cell, containing the genetic material (DNA).

Signup and view all the flashcards

Metabolism

All the chemical reactions occurring within a cell to support life.

Signup and view all the flashcards

Plasma Membrane

The boundary that separates the cell's internal environment (cytoplasm) from the external environment.

Signup and view all the flashcards

Hydrophilic

Water-loving; molecules that are attracted to water.

Signup and view all the flashcards

Hydrophobic

Water-fearing; molecules that repel water.

Signup and view all the flashcards

Phospholipid

A type of lipid with a hydrophilic head and hydrophobic tails.

Signup and view all the flashcards

Phospholipid bilayer

Two layers of phospholipids arranged tail-to-tail, creating a stable barrier in cell membranes.

Signup and view all the flashcards

Prokaryotic cell

A type of cell that lacks a true nucleus and membrane-bound organelles.

Signup and view all the flashcards

Eukaryotic cell

A type of cell that has a true nucleus and membrane-bound organelles.

Signup and view all the flashcards

Bacterial cell wall

A rigid outer layer found in many prokaryotic cells, providing support and protection.

Signup and view all the flashcards

Gram-negative bacteria

Bacteria with an outer membrane that contains lipids and lipoproteins, and a thin cell wall of peptidoglycan.

Signup and view all the flashcards

Gram-positive bacteria

Bacteria lacking an outer membrane and having a thick peptidoglycan cell wall.

Signup and view all the flashcards

Plant cell wall

A rigid layer outside the plasma membrane of plant cells, made primarily of cellulose, providing stability and protection.

Signup and view all the flashcards

Mitochondria

Double membrane-bound organelles found in eukaryotic cells to generate cellular energy.

Signup and view all the flashcards

Chloroplasts

Double membrane-bound organelles found in plant and algal cells that carry out photosynthesis.

Signup and view all the flashcards

Cellular compartmentalization

The division of a cell into separate compartments, each with a specific function.

Signup and view all the flashcards

Binary Fission

A simple form of cell division used by prokaryotes, where the single circular chromosome replicates and the cell divides into two identical daughter cells.

Signup and view all the flashcards

Budding

A form of asexual reproduction where a new organism develops from an outgrowth or bud on the parent organism's body.

Signup and view all the flashcards

Mitosis

A form of cell division that occurs in eukaryotic cells, where the nucleus divides into two nuclei, each with the same number of chromosomes as the parent cell.

Signup and view all the flashcards

Chromosomes

Thread-like structures that contain genetic information in the form of DNA.

Signup and view all the flashcards

Cytokinesis

The division of the cytoplasm of a cell following mitosis or meiosis, resulting in two daughter cells.

Signup and view all the flashcards

Mitotic Spindle

A network of microtubule fibers that forms during mitosis and meiosis to guide the separation of chromosomes.

Signup and view all the flashcards

Centrosome

A structure in the cytoplasm of a cell that serves as the organizing center for microtubules.

Signup and view all the flashcards

Nuclear Envelope

A double membrane that surrounds the nucleus of a eukaryotic cell, separating the genetic material from the rest of the cell.

Signup and view all the flashcards

Microtubules

Hollow tubes of protein that are involved in various cellular processes, including cell shape, movement, and intracellular transport.

Signup and view all the flashcards

Kinetochore microtubule

A type of microtubule that attaches to the centromere of a chromosome during mitosis and meiosis.

Signup and view all the flashcards

Cell Cycle

The series of events a cell goes through from birth to division. It includes Interphase (G1, S, G2) and M-phase (Mitosis).

Signup and view all the flashcards

Interphase

The non-dividing phase of the cell cycle, where the cell grows, copies its DNA (S phase), and prepares for mitosis.

Signup and view all the flashcards

G1 Phase

The first phase of Interphase where the cell grows and prepares for DNA replication.

Signup and view all the flashcards

S Phase

The second phase of Interphase where the cell copies its DNA.

Signup and view all the flashcards

G2 Phase

The third phase of Interphase where the cell continues to grow and prepares for mitosis.

Signup and view all the flashcards

Prophase

The first stage in Mitosis where chromosomes condense, the nuclear envelope breaks down, and the mitotic spindle starts to form.

Signup and view all the flashcards

Metaphase

The second stage in Mitosis where chromosomes line up at the center of the cell forming the metaphase plate.

Signup and view all the flashcards

Anaphase

The third stage in Mitosis where sister chromatids separate and move to opposite poles of the cell.

Signup and view all the flashcards

Telophase

The final stage of Mitosis where the chromosomes are at opposite poles of the cell, the nuclear envelope reforms, and the cytoplasm is divided.

Signup and view all the flashcards

Homologous Recombination

The exchange of DNA between homologous chromosomes during meiosis, resulting in genetic variation. It involves breaking and rejoining DNA segments, creating new combinations of genes.

Signup and view all the flashcards

What does meiosis do to the number of chromosomes?

Meiosis halves the number of chromosomes in a cell, producing daughter cells with only one copy of each chromosome. This is crucial for sexual reproduction, ensuring offspring inherit one set of chromosomes from each parent.

Signup and view all the flashcards

What are the stages of Meiosis?

Meiosis occurs in two main stages: Meiosis I involves the separation of homologous chromosome pairs, creating two haploid cells. Meiosis II involves the separation of sister chromatids within each haploid cell, resulting in four haploid daughter cells.

Signup and view all the flashcards

Crossing Over

The exchange of genetic material between non-sister chromatids on homologous chromosomes during prophase I of meiosis. It leads to genetic diversity in offspring.

Signup and view all the flashcards

Surface Area:Volume Ratio

The relationship between a cell's surface area and its volume. As a cell grows, its volume increases faster than its surface area, making it harder for nutrients to enter and waste products to exit.

Signup and view all the flashcards

Fungal Hyphae Solution

Fungal hyphae are long, thin filaments that increase surface area relative to volume, allowing for efficient nutrient uptake and waste removal.

Signup and view all the flashcards

Muscle Tissue Solution

Muscle cells are often long and cylindrical, increasing surface area for efficient nutrient and oxygen exchange. They also have many mitochondria to provide energy for contraction.

Signup and view all the flashcards

Plant Cell Solution

Plant cells have a large central vacuole that increases surface area for water storage and nutrient transport. They also have a rigid cell wall that provides structural support.

Signup and view all the flashcards

What is the Nucleus?

The nucleus is the control center of eukaryotic cells. It contains the cell's genetic material (DNA) and regulates cellular activity.

Signup and view all the flashcards

Chromatin

The complex of DNA and proteins (histones) that make up chromosomes. It allows DNA to be tightly packaged and organized within the nucleus.

Signup and view all the flashcards

Golgi Apparatus

A network of membrane-bound sacs that sorts and packages proteins and lipids for transport within and outside the cell.

Signup and view all the flashcards

Cis Face

The receiving side of the Golgi Apparatus, facing the nucleus. Proteins and lipids arrive here from the endoplasmic reticulum (ER).

Signup and view all the flashcards

Trans Face

The shipping side of the Golgi Apparatus, facing the plasma membrane. Modified proteins and lipids are packaged into vesicles and sent out from here.

Signup and view all the flashcards

Lysosome

A membrane-bound organelle containing digestive enzymes that break down waste products, worn-out organelles, and engulfed material.

Signup and view all the flashcards

Phagocytosis

A process where a cell engulfs and digests large particles, such as bacteria or food.

Signup and view all the flashcards

Autophagy

A process where a cell recycles its own worn-out organelles or unnecessary components.

Signup and view all the flashcards

Endocytosis

A process where cells take in materials from the external environment by engulfing them in a membrane pocket.

Signup and view all the flashcards

Exocytosis

A process where cells release materials from the inside to the outside by fusing vesicles with the plasma membrane.

Signup and view all the flashcards

Cell Wall

A rigid outer layer found in plant cells and some prokaryotes. It provides structural support and protection.

Signup and view all the flashcards

Cell Division Types

Different cell types divide differently due to their varying structures and DNA organization. Examples include bacteria with binary fission, some yeasts with budding, and most eukaryotes with mitosis.

Signup and view all the flashcards

Sister Chromatids

Two identical copies of a chromosome, connected at the centromere, produced during DNA replication. They separate during mitosis to create two daughter chromosomes.

Signup and view all the flashcards

Cell Cycle Regulation

The process of controlling the timing and sequence of events in a cell's life cycle, ensuring proper growth and division.

Signup and view all the flashcards

G1 Checkpoint

The most important checkpoint in the cell cycle, occurring before DNA replication. It ensures the cell has sufficient nutrients and signals to proceed with division.

Signup and view all the flashcards

M Checkpoint

A checkpoint during mitosis that ensures proper attachment of chromosomes to spindle fibers, guaranteeing accurate chromosome separation during cell division.

Signup and view all the flashcards

G2 Checkpoint

A checkpoint before mitosis that checks for successful DNA replication and checks for any damage, ensuring the DNA is intact before entering the mitotic phase.

Signup and view all the flashcards

Density-Dependent Inhibition

A mechanism that prevents cells from growing uncontrollably. When cells reach a certain density, they stop dividing and forming a single layer.

Signup and view all the flashcards

Cancer Cells

Cells that have escaped the normal cell cycle regulation, growing uncontrollably and forming tumors.

Signup and view all the flashcards

Functions of Cell Division

Cell division serves several crucial functions, including propagation of life, growth and development of organisms, repair and renewal after tissue damage, and sexual reproduction.

Signup and view all the flashcards

Apoptosis

Programmed cell death, a natural process where cells self-destruct, eliminating unnecessary or damaged cells.

Signup and view all the flashcards

Study Notes

Variation in Life Forms

  • Fungi
  • Viruses
  • Animals
  • Plants

Features of Living Organisms

  • Adaptation
  • Order/Organization
  • Control/Regulation
  • Obtaining/Using Energy
  • Growth
  • Reproduction & Heredity
  • Responsiveness
  • Molecular Processes

Replication, Metabolism, and Defining Features of Life

  • Self-replication is a defining feature of life.
  • Self-replication occurs across all organismal levels.
  • Examples: Animals, plants, and bacteria
  • Viruses, computer code/virus, robots/AI

Organismal Level

  • Bacteria, animals, and plants

Molecular Level

  • DNA, proteins, genes, and replication

Theories on the Origin of Life

  • Life continually arises (from non-living things) "spontaneous generation"

  • Life continually evolves (from living things) "Darwinian Evolution"

  • Abiogenesis: Non-living things -> Living things (not continuously)

  • Biogenesis: Living things -> Living things (continuously)

Early Earth

  • 4.54 Billion Years Ago (BYA)
  • Reducing (no oxygen) environment
  • Presence of other gases & water

The First Rain

  • Fossil records indicate liquid water between 4.2-3.8 BYA
  • This supports the cooling of the atmosphere
  • Terrestrial Sources and Extra-Terrestrial Sources

Water and Its Role in Life

  • Water is a key solvent for biological life
  • Moderate temperature and allow floating
  • Other substances dissolve in it.

Conditions For Prebiotic Life

  • Experiment (Miller) simulating early earth prebiotic conditions
  • Gases, water, and energy
  • Analyzed samples showing the presence of amino acids and nucleic acids
  • Link between DNA and amino acids
  • Emerging Hypothesis

The Cell

  • The cell is the molecular machine that allows for self-replication and energy generation.
  • Examples of processes include energy generation and self-replication
  • Relationship between the cell, energy generation, and self-replication

Theories, Evolution, and Compartmentalization of Cells

  • Compartmentalization of cells led to diversification & specialization.

Prokaryotes vs. Eukaryotes

  • Prokaryotes lack a true nucleus and membrane-bound organelles.
  • Eukaryotes have a true nucleus and membrane-bound organelles.

Cellular Structure, Cells

  • Cellular components include the nucleus, plasma membrane, cytoplasm, organelles, and cytoskeleton: providing cell structure and organization, shape, and motility.
  • Cell features, function, and hierarchy are covered.

Cellular Transport

  • Endocytosis (transport into the cell)
  • Exocytosis (transport out of the cell)
  • Lysosomes: membrane compartments containing digestive enzymes
  • Transport within and out of cells, sorting, and packaging.

Cell Division

  • Mitosis (1 cell -> 2 identical daughter cells)
  • Meiosis (1 cell -> 4 genetically unique daughter cells).
  • Processes involved in cell division are demonstrated.

Studying That Suits You

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

Quiz Team

Related Documents

PDF Biology Past Paper - Introduction to Cells

Description

Explore the diverse life forms, their defining features, and the fundamental processes that characterize living organisms. This quiz also delves into the theories concerning the origin of life and the molecular mechanisms that support life. Test your knowledge on adaptation, reproduction, and more!

More Like This

Biology: Five Kingdoms of Life
19 questions

Biology: Five Kingdoms of Life

WellRunHydrogen avatar
WellRunHydrogen
Biology: Variation in Life Forms and Features
63 questions

Biology: Variation in Life Forms and Features

GallantFrancium2355 avatar
GallantFrancium2355
Biology Chapter on Early Life and Photosynthesis
45 questions

Biology Chapter on Early Life and Photosynthesis

HeavenlyBerkelium6080 avatar
HeavenlyBerkelium6080
Use Quizgecko on...
Browser
Open
Browser
Browser