viruses
What is the basic structure of a virion (virus particle)?
capsid (protein coat) surrounding genetic material (DNA or RNA); some have lipid envelopes.
What shape categories are common for bacterial cells (list two)?
Cocci (spherical), bacilli (rod-shaped), spirilla/spirchetes (spiral).
What is a protist (general definition)?
Diverse group of mostly unicellular eukaryotes not classified as animals, plants, or fungi.
Name the three main tissue types in plants and give one function of each.
Dermal (protection, e.g., epidermis), vascular (xylem and phloem for transport), ground (photosynthesis, storage, support).
List the four basic types of animal tissue.
Epithelial, connective, muscle, nervous.
How do viruses differ from living cells in terms of reproduction and metabolism?
Viruses cannot carry out independent metabolism or reproduce without invading host cells; they replicate using host machinery.
What is a cell wall component that differentiates Gram-positive and Gram-negative bacteria?
Peptidoglycan: thick layer in Gram-positive; thin layer plus outer membrane in Gram-negative.
Give one example of a unicellular protist and one multicellular protist (names).
Unicellular: Paramecium. Multicellular (or large multicellular-like): some algae such as kelp (brown algae).
What is the primary function of xylem and what cell types make up xylem?
Xylem transports water/minerals from roots to shoots; tracheids and vessel elements are xylem cell types
Give one main function and one example location in the body for epithelial tissue.
Epithelial function: barrier/protection, absorption, secretion (e.g., intestinal epithelium absorbs nutrients).
Name one common method by which viruses enter host cells.
Attachment via receptor binding (e.g., viral surface proteins binding host receptors), endocytosis, or membrane fusion.
Define binary fission. How does it contribute to bacterial population growth?
Binary fission is asexual division where one bacterial cell splits into two genetically similar daughter cells, enabling exponential growth.
Describe two different nutritional modes protists can have (for example: modes of obtaining energy/nutrients).
Autotrophy (photosynthetic algae), heterotrophy (phagotrophic amoebae), mixotrophy (both, e.g., some dinoflagellates).
Describe the structure and function of the apical meristem.
Apical meristem is a region of actively dividing cells at root and shoot tips responsible for primary growth (lengthening).
Describe the difference between skeletal and smooth muscle in structure and control.
Skeletal muscle: striated, multinucleated, voluntary control; smooth muscle: nonstriated, single nucleus, involuntary in walls of organs.
Explain why antibiotics do not work against viruses
Antibiotics target bacterial structures/processes (cell wall, ribosomes) not present in viruses; antiviral drugs target virus-specific steps.
Describe one way bacteria can exchange genetic material (horizontal gene transfer).
Conjugation (plasmid transfer via pilus), transformation (uptake of free DNA), transduction (phage-mediated transfer).
Explain how Plasmodium (the malaria parasite) fits into the protist category and why it causes disease in humans.
Plasmodium is an apicomplexan protist transmitted by mosquitoes; it invades red blood cells and causes malaria symptoms via its life cycle stages in humans.
Explain how phloem transports sugars and identify the main cell types involved.
Phloem transports sugars via pressure-flow; sieve-tube elements (conducting cells) and companion cells (support metabolic function).
Explain the structure and function of connective tissue, including the role of extracellular matrix.
Connective tissue provides support and binds tissues; ECM includes fibers (collagen, elastin) and ground substance; cell examples: fibroblasts, adipocytes.
Describe the lytic and lysogenic cycles and give one example of a virus that can perform each.
Lytic: virus replicates and lyses host cell (e.g., lytic bacteriophage T4). Lysogenic: viral genome integrates into host genome and replicates with it (e.g., lambda phage; some herpesviruses can be latent).
Explain how endospores help certain bacteria survive harsh conditions and name one genus that forms endospores.
Endospores are highly resistant dormant cells; Bacillus and Clostridium genera form endospores.
Compare and contrast alveolates and amoebozoans in terms of key traits or representative organisms.
Alveolates (have membrane-bound alveoli; include dinoflagellates, apicomplexans) vs. Amoebozoans (amoeboid movement via pseudopodia; include Entamoeba).
Compare primary and secondary growth: where each occurs and what tissues are involved.
Primary growth increases length (apical meristems; primary tissues). Secondary growth increases girth (lateral meristems: vascular cambium, cork cambium producing secondary xylem/wood and bark).
Compare nervous tissue and endocrine signaling: speed of response, mode of signal transmission, and typical function.
Nervous tissue: fast electrical signaling via neurons (synaptic transmission) for rapid coordination. Endocrine signaling: slower, chemical (hormones) via bloodstream for longer-term regulation.