Cell Biology Chapter Quiz

Introduction to Biology

• Biology is the science that studies living organisms and their interactions with each other and their environments.
• Biology encompasses many branches and sub-disciplines, including molecular biology, microbiology, neurobiology, zoology, and botany.
• Living organisms share key properties such as order, sensitivity, reproduction, growth, development, regulation, homeostasis, and energy processing.

The Chemical Foundation Of Life

• All matter, including living organisms, is composed of elements in various combinations.
• Common elements in living organisms include carbon, hydrogen, nitrogen, oxygen, sulfur, and phosphorus.
• These elements form the building blocks of all biological molecules (nucleic acids, proteins, carbohydrates, and lipids).
• Oxygen (O), carbon (C), hydrogen (H), and nitrogen (N) are present in high percentages in living organisms.
• Elements in living organisms are present in different percentages compared to non-living world.

Properties Of Life

• All living organisms share common characteristics (order, sensitivity/response, reproduction, adaptation, growth/development, regulation, homeostasis, energy processing, and evolution).
• Organisms are highly organized, starting from atoms and molecules. Increasing complexity in organisms is exhibited through the formation of organelles, cells, tissues, organs, and organ systems.
• Organisms respond to stimuli (both internal and external).
• Organisms reproduce to create new organisms of the same species.
• Living organisms adapt to their specific environment through changes.
• All living organisms grow and develop.
• Living things regulate functions by maintaining internal conditions (homeostasis).
• Living organisms take energy from their environment to conduct life-processes.
• Organisms evolve over time, changing in characteristics.

Levels Of Organization Of Living Things

• Living things are organized in a hierarchy from atoms to biosphere.
• This hierarchy includes atoms, molecules, organelles, cells, tissues, organs, organ systems, organisms, populations, communities, ecosystems, and the biosphere.

Biological Macromolecules

• Food provides the body with critical nutrients for survival in the form of biological macromolecules.
• These macromolecules (polymers) are built from smaller organic molecules (monomers).
• Major classes of biological macromolecules include: carbohydrates, lipids, proteins, and nucleic acids.

Cytology

• A cell is the basic unit of life.
• All cells share four basic components : plasma membrane, cytoplasm (containing cytosol), DNA, and ribosomes.
• There are two types of cells: prokaryotic and eukaryotic.
• Prokaryotic cells lack a nucleus or other membrane-bound organelles, whereas eukaryotic cells have a nucleus and various organelles
• Eukaryotic cells contain a nucleus, endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria, ribosomes, peroxisome and other organelles.
• Prokaryotic and eukaryotic cells differ in structure and the presence or absence of membrane- bound organelles.

Cell Components

• Nucleus contains genetic material (DNA) and directs cell activities
• Cytoplasm includes cytosol and various organelles with different specialized functions
• Endoplasmic reticulum (ER) is involved in protein and lipid synthesis.
• Golgi apparatus modifies, sorts, and packages cell products.
• Mitochondria produce ATP (cellular energy).
• Ribosomes synthesize proteins.
• Lysosomes digest cellular waste and debris.
• Peroxisomes break down fatty acids.
• Cytoskeleton provides structural support and facilitates cell movement.
• Centrioles play a role in cell division.
• Cilia and flagella aid in cell movement.
• Microvilli increase the surface area for absorption.

Cell Cycle

• The cell cycle is a series of events that prepares a cell for division.
• The cell cycle is divided into two major parts; interphase, which is a long period during which the cell increases its size and contents by duplicating its DNA, and mitosis, which is a shorter period during which the cell divides its nucleus and cytoplasm,
• Interphase is divided into G1, S, and G2 phases.
• Mitosis is a process that results in two identical daughter cells with the same chromosome number.
• The processes of mitosis are Prophase, Metaphase, Anaphase, and Telophase.
• Meiosis is a special type of cell division that reduces the chromosome number by half
• Meiosis is divided into Meiosis I and II. Two types of cells result from meiosis.

Gametogenesis

• Gametogenesis is the development of gametes through the process of meiosis.
• Spermatogenesis involves the production of sperm in the testes of males.
• Oogenesis involves the production of ova in the ovaries of females

Histology Of Tissues

• Epithelial tissue forms outer coverings and linings.
• Connective tissue binds other tissues together and provides support.
• Muscle tissue contracts to produce movement.
• Nervous tissue transmits signals throughout the body.

Principles of Heredity

• Genetic traits are passed from parents to offspring in specific patterns.
• The principles of segregation and independent assortment describe how these traits are inherited.

The Chromosome Theory Of Inheritance

• Genes are located on chromosomes which segregate during meiosis explaining Mendel's principles.
• Non-disjunction during meiosis can lead to disorders like Down syndrome and abnormal chromosome numbers.

Molecular Genetics

• DNA is the genetic material, containing the sequence of bases that controls the synthesis of proteins.
• DNA replication follows a semi-conservative model, with each new DNA molecule containing one original strand and one newly synthesized.
• The central dogma describes the flow of genetic information from DNA to RNA to protein.
• Transcription produces mRNA from DNA, while translation converts mRNA into protein.
• Mutations in DNA can alter the genetic code, potentially affecting the characteristics of an organism.

Environmental effects on gene expression

• Environmental factors influence phenotypic expression.
• Expressivity: Degree of expression of a genotype
• Penetrance: Proportion of individuals with a particular genotype that exhibit the associated phenotype

Polygenic Inheritance

• Many traits are influenced by multiple genes, exhibiting continuous variation.
• Height and other traits exhibit continuous variation.

Other Topics

• Pleiotropy: one gene affects multiple traits

• Multiple Genes: various genes contribute to the phenotype via interaction or epistasis.

• Genetic Mutations: changes in DNA base pair sequence that can alter the protein product

• Linkage of Genes: genes located close together on the same chromosome tend to be inherited together.

• Chromosome Abnormalities: can include deletion, duplication, inversion, and translocation

• DNA Replication: the process of copying DNA using the original strand as a template

• Protein Synthesis: the process of building proteins at the ribosome using the code in mRNA.

• Blood Typing: classifies blood by antigens on the surface of red blood cells, crucial in transfusions.

• Rh Blood Groups: another set of antigens, leading to problems in some pregnancies; important in blood transfusions.

• Immunological system: describes the system responsible for recognizing and eliminating pathogens.

• Principles of the Immune System: describe the system of immune responses in vertebrates, summarizing the different cell types and roles involved

• Immunity: acquired immunity, innate immunity (cells and response to pathogens).

• The Cardio-Vascular system: circulatory system in vertebrates

• The Heart: the structure and function of the heart are explained.

• Blood vessels: arteries, veins, capillaries

• Patterns of circulation.

• Blood pressure.

• Lymph system

• Body plans (asymmetry, radial, bilateral)

• Homeostasis: regulation and maintenance of internal conditions in animals.

• Neural control of thermoregulation.

• Thermoregulation: mechanisms that control animal body temperature

• The Respiratory system: gas exchange and respiration

• The Excretory System

• The Endocrine system: hormones controlling development , processes, and behaviors.

• Digestive system