PLSC 161 Final Exam Review

Do plants have the same scientific name in other countries?

Yes, a scientific name is derived from Latin/Greek roots.

What is biological nitrogen fixation?

The conversion of N2 into NH3, occurring in the nodules of legume plants with the help of rhizobium bacteria.

What is a stomata?

Natural microscopic openings in plants that facilitate respiration, transpiration, and photosynthesis.

What is a plant hardiness zone?

A graph, table, or map created by the USDA showing what plants grow well in certain areas.

What is required for all seeds to germinate?

Moisture/water, oxygen, and temperature.

What is an abiotic disease?

A disease caused by non-living factors, such as iron deficiency or natural disasters.

What are the three weed distribution patterns?

Random, regular, and patchy.

What is a perfect flower?

A flower that includes stigma, style, ovary, ovules, stamen, anther, and filament.

What is diapause?

The dormant state for insects.

What is a dicot?

A plant with 2 cotyledons, examples include soybean or peanut plants.

What percent of weeds are native to North America?

40%.

What is a lichen?

A symbiotic relationship between algae and fungi, where algae provide carbohydrates and fungi provide protection.

Do plants with bright colors have lightweight pollen?

No, brighter flowers are more dependent on pollinators.

What is the difference between epigeal and hypogeal emergence?

Epigeal emergence occurs above ground, while hypogeal emergence occurs below ground.

What is desired during plant domestication?

Higher germination rate, synchrony in flowering, and reducing seed shattering.

What is a vascular system in plants?

The system that includes xylem (water) and phloem (sugar and carbohydrates) to transport nutrients.

Where would you find a plant species highest biodiversity?

At the center of origin.

What are the elements of the disease triangle for the Irish Potato Famine?

A: Environment (cool and wet), B: Pathogen (Phytophthora infestans), C: Host (lumper).

What does IPM stand for?

Integrated Pest Management.

What do weeds take away from crops?

Light, water, nutrients, and space.

What type of seeds can you save for future planting?

Variety/cultivar; hybrid seeds cannot be saved.

What is a nematode?

An unsegmented roundworm and the most abundant microcellular organism on earth, mainly feeding on bacteria.

What do nematodes typically feed on in soil?

Bacteria

What advantages does hybrid seed provide?

Vigor and uniformity.

What is the difference between germination and emergence?

Germination is the formation of the radicle; emergence refers to whether it is epigeal or hypogeal.

How much value can landscape plants add to your home?

15% of home value.

What are the differences between annual and perennial flowers?

Annuals complete their life cycle within a year; perennials persist for multiple years.

What is the difference between a pathogen and a disease?

Pathogen has no host and has a scientific name; disease has a host.

What crops require pollination?

Coffee, fruits, berries, and nuts.

Where does photosynthesis occur in plants?

In the mesophyll layer, specifically within mesophyll cells that contain chloroplasts.

How does temperature influence photosynthesis?

Optimal temperatures yield the highest rates of photosynthesis, while extreme temperatures can inhibit activity and reduce efficiency.

Where do trees get their biomass from?

From the atmosphere through photosynthesis.

What factors influence nitrogen fixation?

The health of the plant, determined by light, water, nutrients, and space.

How do plants decompose?

Plants decompose through the action of microorganisms, fungi, and detritivores, which break down organic matter, returning nutrients to the soil and completing the nutrient cycle.

Why do damaged trees have more lichens?

Lichens do not have to compete with live trees/plants for photosynthesis.

What is the difference between natural selection and artificial selection?

Natural selection occurs without human intervention; artificial selection is driven by human choices.

What is the difference between winter annual weeds and summer annual weeds?

Winter annuals grow when there is less competition and more water; summer annuals grow at different times.

What influences a plant’s phenotype?

The genotype and the environment.

How would you differentiate SCN from a nodule?

SCN consists of cysts with eggs; nodules are part of the plant.

What is pH, and how does it influence plant health?

Soil pH measures acidity or alkalinity, impacting plant health and growth.

Do wild species germinate more uniformly than domesticated ones?

No, wild species have a lower germination rate compared to domesticated species, which often exhibit more uniform germination due to selective breeding.

What does USDA stand for?

United States Department of Agriculture.

What is one goal of breeders when enhancing root biomass in crops?

To create larger plants=better/more photosynthesis.

What is the difference between photosynthesis and respiration?

Photosynthesis converts CO2 to O2; respiration converts O2 to CO2.

What is meristematic tissue?

Tissue in meristematic regions that undergoes rapid cell division.