botany midterm

Question 1

what is terroir

Answer 1

the combination of soil, local geography, climate, pests, microbes that affect plant growth

Question 2

what is soil composed of

Answer 2

solids (minerals, organic matter)
liquids (water, nutrient solutions)
gases (nitrogen, oxygen, co2)

Question 3

what is a colloid in soil

Answer 3

a substance dispersed through another substance, soil is an example of a colloid

Question 4

what are the two types of soil colloids

Answer 4

1. organic colloids - decomposed organic matter (humus)
2. inorganic colloids - clay minerals, hydrous oxides

Question 5

what are the three soil horizons

Answer 5

topsoil - most organic matter, most fertile, biologically active
subsoil - contains iron oxide, clay and little organic matter
c horizon - soil base, composed of weathered rock

Question 6

3 types of soil

Answer 6

sand - large particles, drains quick
clay - tiny particles, retains water
silt - fine particles like sediment

Question 7

what is loam soil

Answer 7

balanced mixture of sand, silt and clay, ideal for plant growth

Question 8

importance and meaning of humus

Answer 8

fully decomposed organic matter that resists further breakdown, acts as a buffer for pH and moisture changes

Question 9

3 primary elements in fertilizer

Answer 9

nitrogen, phosphorus and potassium

Question 10

macronutrients vs micronutrients

Answer 10

macronutrients - needed in large amounts (nitrogen, phosphorus, potassium)_
micronutrients - needed in small amounts (iron, zinc, copper)

Question 11

two phases in a moss plant’s life cycle

Answer 11

sporophyte - diploid 2n - produces spores (Mitosis)
gametophyte - haploid, n - produces gametes (meiosis)

Question 12

what is domestication

Answer 12

selection of desirable genetic traits and cultivation through watering, plowing and fertilization

Question 13

phenotype vs genotype

Answer 13

genotype - genetic code
phenotype - physical trait you can see

Question 14

what is breeding in agriculture

Answer 14

selectively reproducing plants and animals with desirable genetic traits

Question 15

how do domesticated plants compare to their wild relatives

Answer 15

lower fitness to survive in the wild (weeds survive more than a domesticated strawberry for example)

Question 16

parallel domestication

Answer 16

independent domestication of the same species by different cultures without direct interaction (for example different cultures in east asia and israel domesticated brassica species - like kale, broccoli, cabbage - for food)

Question 17

significance of root crops

Answer 17

food secruity

Question 18

ignore

Answer 18

food security

Question 19

common characteristics of weeds

Answer 19

thrive in nutrient rich environments
often reproduce sexually and asexually (dandelions)
usually WILD relatives of domesticated plants

Question 20

how can crop loss be reduced

Answer 20

avoid monocultures and oligocultures - grow more than one/a few crops.
maintain diversity in crops and local environment

Question 21

what is allelopathy

Answer 21

process where plants release chemicals to harm other plants (to outcompete them)

Question 22

what is the function of primary metabolites

Answer 22

provide energy to the plants (and animals/humans that eat them)
carry genetic information

Question 23

examples of primary metabolites

Answer 23

carbs, protein, fat, nucleic acid

Question 24

secondary metabolites

Answer 24

organic compounds not directly involved in growth, important for defence and attraction

Question 25

some functions of secondary metabolites

Answer 25

chemical repellents - protect against herbivores chemical attractants - help with pollination and seed dispersal essential to evolution - plants invest energy in producing them

Question 26

example of PHYSICAL plant defense

Answer 26

thorns - modified branches that physically protect the plant

Question 27

where do meiosis and mutations occur (in plants)

Answer 27

in the anther and ovule

Question 28

what happens when a nucleotide typo occurs in meiosis

Answer 28

it gents translated into genetic information, potentially leading to mutations

Question 29

what is a locus

Answer 29

physical location of a gene on a chromosome

Question 30

what is an allele

Answer 30

form of a gene at a locus (example - P for purple flower, p for white flower)

Question 31

genotype vs phenotype

Answer 31

genotype-genetic makeup - WW, Ww, ww phenotype-PHYSICAL expression of genotype

Question 32

what does meiosis produce

Answer 32

4 haploid (1n) daughter cells that experience recombination before splitting

Question 33

why do multicellular eukaryotes dominate earth

Answer 33

mutation, recombination and independent assortment which gives rise to genetic diversity

Question 34

advantage of sexual reproduction

Answer 34

genetic diversity!

Question 35

outcrossing vs inbreeding

Answer 35

outcrossing - mating with a genetically different individual inbreeding - mating with a genetically similar individual (like a cousin)

Question 36

inbreeding depression

Answer 36

reduced fitness in a population due to closely related individuals mating (cousins)

Question 37

where does photosynthesis take place

Answer 37

in the chloroplast, specifically in the thylakoid

Question 38

what does photosynthesis require and produce

Answer 38

require - light produce - ATP and NADPH *(energy)

Question 39

what are chlorophyll and carotenoids important for

Answer 39

chlorophyll - captures light for photosynthesis carotenoids - acts as an antioxidant and are the primary source of vitamin A

Question 40

how do plants adapt to dry/hot environments

Answer 40

close their stomata to reduce water loss

Question 41

why is nitrogen important for plants

Answer 41

essential for growth, usually supplied through fertilizer

Question 42

glycolysis

Answer 42

process of breaking down organic carbon, anaerobic (does not require oxygen) and requires initial energy investment, but produces more energy

Question 43

carbon respiration (krebs cycle)

Answer 43

H20 consumed, CO2 released aerobic - requires oxygen

Question 44

what is a compound leaf

Answer 44

a leaf made up of multiple leaflets

Question 45

how can you tell a simple leaf vs compound leaf

Answer 45

simple - bud in the leaf axil compound - NO bud in the leaflet axil, subleaf branch comes from a single point

Question 46

components of the epidermis of a plant

Answer 46

stomata - gas exchange pore cuticle- wax layer for protection mesophyll - chloroplast containing vasularbundle - phloem and xylem (transport system) inside

Question 47

how are cactus stems/leaves different from other plants

Answer 47

cacti have modified stems and leaves for water storage and protection

Question 48

transpiration

Answer 48

the loss of water vapor from plants, mostly via stomata

Question 49

function of roots

Answer 49

anchorage, absorption of water/nutrients, storage of food, conduction of nutrients and water

Question 50

two maine types of root systems

Answer 50

taproot - primary root with lateral branches (dicot) fibrous root - thin root that arise from the stem (monocot)

Question 51

function of root hairs

Answer 51

increase surface area for better absorption of water and nutrients

Question 52

root cap function

Answer 52

structure that protects apical meristem and senses gravity

Question 53

mycorrhiza

Answer 53

a fungus root association that helps plants absorb nutrients

Question 54

male reproductive organs of a p[lant

Answer 54

sepal and petal all petals together are called the corolla

Question 55

female reproductive organs of plant

Answer 55

stamen, ovary, ovule ovary - becomes fruit ovule - becomes seed

Question 56

what is a flower

Answer 56

modified branch in angiosperm that performs reproductive funcitons

Question 57

what is special about grass flowers

Answer 57

reduced for wind pollination

Question 58

where does pollination occur

Answer 58

on stigma, where pollen travels down the pollen tube to fertilize the ovule

Question 59

what is double fertilization in plants

Answer 59

1 - diploid to haploid 2 - haploid to triploid - forms endosperm

Question 60

three layers of a fruit

Answer 60

exocarp - outer skin mesocarp - fleshy part endocarp - pit/stone

Question 61

two types of ovary positioning

Answer 61

inferior ovary - below attachment of sepal, petal and stamen superior ovary - ABOVE attachment of sepal, petal and stamen

Question 62

4 macromolecules essential for life

Answer 62

carbs, lipids, protein and nucleic acid

Question 63

tropism

Answer 63

growth response of a plant due to an environmental stimulus

Question 64

gravitropism

Answer 64

plant’s growth response to gravity

Question 65

phototropism

Answer 65

plant’s growth response to light, causing it to grow towards the sun

Question 66

what hormone controls tropism

Answer 66

AUXIN