Living Earth Spring Final Review

1

The parts of a chromosome include: chromatids, centromere, telomeres, and genes. A sketch would show two sister chromatids connected at the centromere, with telomeres at the ends.

2

Homologous chromosomes are pairs of chromosomes that have the same genes in the same order. One comes from the mother and one comes from the father.

3

A gene is a segment of DNA that codes for a specific trait. Genes are found on chromosomes.

4

Crossing over is the exchange of genetic material between homologous chromosomes during meiosis. It causes genetic recombination by creating new combinations of alleles.

5

Nondisjunction is the failure of chromosomes to separate properly during meiosis. It can lead to aneuploidy, where cells have an abnormal number of chromosomes (e.g., Down syndrome).

6

Monohybrid crosses are crosses between individuals that involve one pair of contrasting traits.

7

A karyotype is a visual representation of an individual's chromosomes. A human karyotype has 46 chromosomes (23 pairs).

8

Dominant traits are traits that are expressed when at least one allele for that trait is present. Recessive traits are traits that are only expressed when two alleles for that trait are present.

9

An allele is a variant form of a gene.

10

A homozygous genotype is a genotype in which both alleles for a trait are the same (e.g., AA or aa). Synonyms include 'purebred' or 'true-breeding'.

11

A heterozygous genotype is a genotype in which the alleles for a trait are different (e.g., Aa). Synonyms include 'hybrid'.

12

Gregor Mendel was important because he discovered the basic principles of heredity through his experiments with pea plants.

13

Phenotype is the observable characteristics of an organism, while genotype is the genetic makeup of an organism.

14

Codominance is a situation in which both alleles in a heterozygous individual are expressed.

15

The different blood types are A, B, AB, and O. Blood type is an example of codominance because in type AB blood, both the A and B alleles are expressed.

16

0% Blonde

100% Brown

17

a. BB

b. WW

c. BW

18

0% Type O

50% Type A

50% Type B

0% Type AB

19

The chart would need to be provided to label the biological sex, genotype, and phenotype of each individual. Dimples are recessive, so individuals with dimples would be 'dd', and those without would be either 'Dd' or 'DD'. Biological sex is determined by chromosomes (XX for female, XY for male).

20

The three types of weathering are:

1. Physical weathering: breaking down rocks without changing their chemical composition (e.g., frost wedging).
   

2. Chemical weathering: breaking down rocks by changing their chemical composition (e.g., acid rain dissolving limestone).
   

3. Biological weathering: breaking down rocks by living organisms (e.g., tree roots growing into cracks).

21

Deforestation and erosion are related because the removal of trees (deforestation) leaves the soil exposed, making it more susceptible to erosion by wind and water.

22

The Ring of Fire is located around the Pacific Ocean. The location of volcanoes and plate boundaries are related because volcanoes often form at plate boundaries, where tectonic plates interact.

23

The three types of plate boundaries are:

1. Convergent boundaries: where plates collide.
   

2. Divergent boundaries: where plates move apart.
   

3. Transform boundaries: where plates slide past each other.

24

Evolution is the change in the heritable characteristics of biological populations over successive generations.

Microevolution refers to small-scale changes in allele frequencies within a population, while macroevolution refers to large-scale evolutionary changes, such as the formation of new species.

25

1. Fossils: Fossils provide a record of past life forms and show how organisms have changed over time.
   

2. Anatomy and structures: Homologous structures (similar structures in different species) suggest common ancestry. Analogous structures (different structures with similar functions) show convergent evolution.
   

3. Embryology: Similarities in the embryonic development of different species suggest common ancestry.
   

4. DNA Sequences: Similarities in DNA sequences among different species suggest common ancestry.

26

Natural selection is caused by differential survival and reproduction due to variations in traits. Selection pressure is any factor that affects survival and reproduction, leading to natural selection.

27

Adaptations are traits that enhance an organism's survival and reproduction in its environment. They relate to natural selection because individuals with advantageous adaptations are more likely to survive and reproduce, passing on those traits to their offspring.

28

Adaptive radiation in regards to the Galapagos Finches refers to the diversification of finches into different species with specialized beaks adapted to different food sources.

29

Artificial selection is the selective breeding of plants and animals by humans to produce desired traits. An example is the breeding of dogs for specific characteristics.

30

Homologous structures are structures in different species that have a similar underlying anatomy but may have different functions. An example is the forelimbs of humans, bats, and whales.

31

Vestigial structures are structures in an organism that have lost their original function over time. An example is the human appendix.

32

A cladogram is a diagram that shows the evolutionary relationships among a group of organisms. It is read by tracing the branches to see how closely related different groups are.

33

A mutation is a change in the DNA sequence. Mutations can lead to evolution by introducing new genetic variation into a population.

34

A gene pool is the total collection of genes in a population at any one time. Allele frequency is the proportion of different alleles in a population.

35

Population: A group of individuals of the same species living in the same area. Example: A herd of deer in a forest.

Community: All the different populations that live together in an area. Example: All the plants, animals, and microorganisms in a forest.

Ecosystem: All the living (biotic) and nonliving (abiotic) things in an area, interacting. Example: A forest ecosystem includes trees, animals, soil, water, and air.

Biome: A large geographic area characterized by specific climate conditions, animal populations, and plant populations. Example: A tropical rainforest.

Biosphere: All the parts of Earth where life exists, including land, water, and air.

36

Abiotic refers to non-living components of an ecosystem (e.g., sunlight, water, soil). Biotic refers to living components of an ecosystem (e.g., plants, animals, bacteria).

37

Biosphere: The regions of the surface, atmosphere, and hydrosphere of the earth occupied by living organisms.

Hydrosphere: All the water on Earth, including oceans, lakes, rivers, and groundwater.

Geosphere: The solid parts of Earth, including the crust, mantle, and core.

Atmosphere: The layer of gases surrounding Earth.

38

Exponential growth: Population grows at an increasing rate, forming a J-shaped curve.

Logistic growth: Population growth slows as it reaches carrying capacity, forming an S-shaped curve.

39

Carrying capacity is the maximum population size that an environment can sustain. Changes in resource availability (e.g., food, water, shelter) can cause the carrying capacity to change.

40

Population limiting factors are factors that limit the growth of a population, such as food availability, water, space, and disease.

41

A density-dependent factor is a limiting factor that depends on population size (e.g., disease). A density-independent factor is a limiting factor that affects all populations regardless of size (e.g., natural disasters).

42

A niche is the role an organism plays in its environment, including its habitat, food sources, and interactions with other species. A habitat is the physical environment where an organism lives.

43

A symbiotic relationship is a close and long-term interaction between two different species.

44

Parasitism: One organism benefits and the other is harmed. Example: A tick on a dog.

Mutualism: Both organisms benefit. Example: Bees pollinating flowers.

Commensalism: One organism benefits and the other is neither harmed nor helped. Example: Barnacles on a whale.

45

1. Producer (autotroph): An organism that makes its own food. Example: Plants.
   

2. Consumer (heterotroph): An organism that eats other organisms. Example: Animals.
   

3. Primary consumer: An organism that eats producers. Example: Herbivores like cows.
   

4. Secondary consumer: An organism that eats primary consumers. Example: Carnivores like snakes.
   

5. Decomposer: An organism that breaks down dead organisms. Example: Fungi.

46

A food chain is a linear sequence of organisms through which nutrients and energy pass as one organism eats another. A food web is a network of interconnected food chains. The arrows show the direction of energy flow.

47

The rule of 10% states that only about 10% of the energy stored in one trophic level is passed on to the next trophic level.

48

Resistance is the ability of a population to withstand disturbance. Resilience is the ability of a population to recover from disturbance.

49

Biomagnification is the increasing concentration of toxins in organisms at higher trophic levels. Top predators accumulate the most toxins because they consume organisms from lower trophic levels, accumulating the toxins present in those organisms.

50

Climate is the long-term average of weather conditions in a region. Climate change refers to significant and lasting changes in these long-term averages, such as temperature and precipitation patterns.

51

The human population has been experiencing exponential growth. Factors that affect human population growth include birth rates, death rates, and migration.

52

Levels of carbon dioxide and temperature have increased over time, and they are positively correlated. As carbon dioxide levels increase, temperature also increases due to the greenhouse effect.

53

Tropical climates are being affected by climate change through increased temperatures, changes in precipitation patterns, and increased frequency of extreme weather events.

54

Arctic climates are being affected by climate change through rising temperatures, melting ice, and changes in sea levels.

55

Humans are affecting the Pika population through habitat destruction and climate change, which is causing their habitat to shrink and become unsuitable.

56

Humans are negatively affecting the biosphere through deforestation and pollution.

Humans are negatively affecting the geosphere through mining and soil erosion.

Humans are negatively affecting the hydrosphere through pollution and overconsumption of water.

Humans are negatively affecting the atmosphere through greenhouse gas emissions.

57

Sustainable agriculture is farming practices that meet the needs of the present without compromising the ability of future generations to meet their own needs. It is important to the planet and slowing the effects of climate change because it reduces environmental impacts and promotes biodiversity. Carbon sequestration is the process of capturing and storing atmospheric carbon dioxide.