General Biology 1 Quarter Exam Review

Comprehensive practice flashcards covering cell theory, cellular organelles, cell cycle and mitosis, plant and animal tissue types, and core biological concepts.

What is the main distinction between an adaptation and a response to a stimulus?

A response to a stimulus occurs within the lifetime of an individual organism, whereas an adaptation develops in a population over many generations.

What is the definition of homeostasis?

The maintenance of relatively stable internal conditions despite external changes.

What is the progression of biological organization from simplest to most complex?

$$\text{Cell} \rightarrow \text{Tissue} \rightarrow \text{Organ} \rightarrow \text{Organ System} \rightarrow \text{Organism}$$

What are the three classical principles of Cell Theory?

1. All living organisms are composed of one or more cells.
2. The cell is the basic structural and functional unit of life.
3. All cells arise from pre-existing cells.

What contribution did Matthias Schleiden make to cell theory?

He concluded that plants are composed of cells.

What contribution did Theodor Schwann make to cell theory?

He concluded that animals are composed of cells.

What contribution did Rudolf Virchow make to cell theory?

He proposed that cells arise from existing cells.

What does Rudolf Virchow's principle "Omnis cellula e cellula" mean?

Every cell comes from another cell.

Why are viruses considered exceptions to the cell theory?

They are acellular (not made of cells), consist of genetic material surrounded by a protein coat, cannot reproduce independently, and depend on a host cell for replication.

What four basic features are present in all living cells?

Plasma membrane, cytoplasm, genetic material, and ribosomes.

How does DNA structure differ between prokaryotic and eukaryotic cells?

Prokaryotes usually have circular DNA, whereas eukaryotes have linear chromosomes.

What primary function does the nucleolus serve?

It is the main site of ribosomal RNA (rRNA) synthesis and ribosome assembly.

What is the functional difference between free ribosomes and ribosomes attached to the Rough ER?

Free ribosomes usually produce proteins used inside the cell, while attached ribosomes usually produce proteins intended for secretion, membranes, or specific organelles.

What are the major functions of the Smooth Endoplasmic Reticulum?

Lipid synthesis, phospholipid production, steroid synthesis, detoxification of drugs and toxins, and calcium storage.

What is the correct logical sequence of the protein secretion pathway?

$$\text{Ribosome} \rightarrow \text{Rough ER} \rightarrow \text{Transport Vesicle} \rightarrow \text{Cis Golgi} \rightarrow \text{Golgi Modification} \rightarrow \text{Trans Golgi} \rightarrow \text{Secretory Vesicle} \rightarrow \text{Plasma Membrane} \rightarrow \text{Outside the Cell}$$

What are the functions of lysosomes inside the cell?

They contain hydrolytic digestive enzymes to digest macromolecules, destroy damaged cellular components, recycle cellular materials, and break down foreign particles.

What are grana in chloroplasts?

Stacks of thylakoids.

What is the function of the tonoplast in plant cells?

It is the membrane surrounding the central vacuole that regulates the movement of substances, including water and ions, between the cytoplasm and vacuole.

What sub-phases make up Interphase in the cell cycle?

$$G_1 \rightarrow S \rightarrow G_2$$

What key event occurs during the S phase of the cell cycle?

DNA replication occurs, forming two identical sister chromatids per chromosome.

What molecular complex formed by Cyclin B and CDK1 regulates the transition from $G_2$ to M phase?

Maturation-Promoting Factor (MPF).

What is the correct sequential order of stages in mitosis?

$\text{Prophase} \rightarrow \text{Metaphase} \rightarrow \text{Anaphase} \rightarrow \text{Telophase}$ (PMAT).

What protein complex keeps sister chromatids together prior to their separation in anaphase?

Cohesin.

How do karyokinesis and cytokinesis differ?

Karyokinesis is the division of the cell nucleus, whereas cytokinesis is the physical division of the cytoplasm.

Why is binary fission in bacteria distinct from mitosis?

Binary fission occurs in prokaryotes that lack a nucleus and do not undergo the eukaryotic PMAT mitotic sequence.

What is the primary function and location of apical meristems?

Apical meristems are located near root tips and shoot tips and are responsible for primary growth (increase in plant length).

How do collenchyma and sclerenchyma tissues differ in structure and function?

Collenchyma consists of living cells with unevenly thickened primary walls that provide flexible support. Sclerenchyma consists of cells with thick, lignified secondary walls (usually dead at maturity) that provide rigid, strong support.

What substance in cork cells provides waterproofing in periderm?

Suberin.

What are lenticels?

Openings associated with woody tissues that permit gas exchange.

Which epithelial tissue type consists of a single layer of thin, flat cells suited for rapid diffusion and filtration?

Simple squamous epithelium.

What is the functional difference between cilia and microvilli?

Cilia function in moving materials across the cell surface, whereas microvilli function to increase surface area for absorption.

Where are chondrocytes located in cartilage tissue?

In lacunae.

How do skeletal, cardiac, and smooth muscle tissues compare in terms of striation and voluntary control?

Skeletal: Striated and Voluntary. Cardiac: Striated and Involuntary. Smooth: Non-striated and Involuntary.

What structural features connect cardiac muscle cells to facilitate communication and coordinated contraction?

Intercalated discs.

What is the directional difference in signal conduction between dendrites and axons?

Dendrites receive signals and conduct them toward the cell body, whereas axons conduct action potentials away from the cell body.

What is apoptosis and why is it important?

Apoptosis is programmed cell death that eliminates cells with unrepairable DNA damage, unneeded cells, or cells involved in developmental structures, protecting the organism from potential harm.

How many chromosomes are in human somatic cells versus human gametes?

Human somatic cells are diploid ($2n$) with 46 chromosomes, while human gametes are haploid ($n$) with 23 chromosomes.