Bio exam 4

The following is a list of events that were involved in the formation of self-replicating living cells. Which one of the following best represents the order in which these events are believed to have occurred?

3, 1, 4, 2 formation of simple organic molecules from atmospheric gases, formation of RNA, formation of a lipid-protein membrane, enclosure of small organic molecules within a membrane

Commercial logging by European countries in the Ivory Coast has reduced the pristine 70 million acres of forests that once existed to about

5-7 million acres.

The figure above shows an evolutionary tree. At which of the following locations does this map indicate extinction?

A and D

When the fetal pituitary gland matures, it releases ________, which triggers the sequence of events referred to as

ACTH

For sperm to be able to penetrate the zona pellucida of the egg, enzymes are released from the ________

Acrosome

he formation of the ________ cavity and the differentiation of the embryonic disk into ectoderm and endoderm occurs at the end of the pre-embryonic period of development.

Amniotic

The process of producing energy from organic substrates in the absence of oxygen is called ________ metabolism

Anaerobic

When considering evolution, structures of present-day organisms that have the same function but did not develop from the same ancestral structure are said to be ________.

Analogous

The largest hole in the ozone layer occurs in the stratospheric layer over

Antarctica.

Based on the figure above, which one of the following appears to be in the direct ancestral path of modern humans?

Australopithecus afarensis

The figure above shows a human sperm. Which part of the sperm contains the most mitochondria for generating ATP?

B

The ozone layer can be destroyed by pollutants such as

CFCs

The two countries that are the largest emitters of greenhouse gasses are

China and the United States of America.

The best-known extinction during which all dinosaurs died out completely occurred during the ________ time period.

Cretaceous Period

The process of evolution ultimately depends on changes that occur in the ________ of organisms.

DNA

An ________ pregnancy is one where the blastocyst implants somewhere outside of the uterus, such as in the oviduct.

Ectopic

Which one of the following is TRUE regarding fossils?

Even though fossils from more than 200,000 different species have been found, the fossil record remains incomplete.

Movement of individuals into or out of population that results in a redistribution of alleles is called ________.

Gene flow

The figure above shows the skeletal structure of the forelimbs of several vertebrates. Because these skeletal elements are similar in form and are believed to have evolved from a common ancestral structure, they are said to be

Homologous

During puberty, the secretion of GnRH causes the secretion of ________, which in turn stimulate(s) the production of sex hormones.

LH and FSH

The early embryos of vertebrates follow the same pathway of development; one structure that all vertebrate embryos have in common is the ________, which serves as a primitive support structure

Notochord

The early atmosphere of Earth did not contain the gas ________; it is believed that life as we know it would not have evolved if this gas had been present.

O2

One hypothesis for why we age, or at least why our cells age, is that every time that mitosis occurs, ________ at the ends of chromosomes shorten, and eventually the cell runs out of these units at the ends of chromosomes.

Telomeres

Why is taking the first breath hard work for the newborn?

The surface tension within the alveoli is very high.

The extra-embryonic membrane known as the ________ is the source of germ cells that eventually develop into gametes.

Yolk sac

To reduce the extent of this damaging phenomenon, many power plants have been required to install systems to remove and capture sulfur dioxide from their emissions

acid rain

When conditions are right, many new species may develop in a relatively short period of time from a single ancestor. Such short bursts of evolutionary activity are called

adaptive radiation

The ability to extract oxygen from the environment and use it to make energy is called

aerobic metabolism.

The blood vessels of the umbilical cord are derived from which one of the following structures?

allantois

The blastocyst begins to form a second hollow cavity that will eventually become the

amniotic cavity.

The wings of birds and insects share similar functions but evolved from different structures; therefore, these wings

analogous

During the development following fertilization, the morula becomes a hollow ball of cells called the

blastocyst.

The figure above shows the development of the human embryo during days 19-24. Which of the following organs forms from the ectodermal folds of the embryo?

brain and spinal cord

taxonomy

branch of science that focuses on classifying and naming life-forms

cleavage

cells divide rapidly, resulting in a ball of unspecialized cells

growth

cells increase in number and size

differentiation

cells take on a certain structure and function

There are a series of cell divisions that produce no cell growth during the first four days following fertilization. This process is referred to as

cleavage

Cytochrome c is a small protein that is found in present-day organisms. Comparison of the structure of cytochrome c from different organisms to infer evolutionary relationships would be part of the science involving

comparative biochemistry

The process of ________ has had a major impact on species distributions worldwide.

continental drift

The main human activities that have raised atmospheric CO2 levels are

deforestation and burning fossil fuels.

Fertilization is completed when the sperm nucleus fuses with the ________.

egg nucleus

morphogenesis

embryo undergoes rapid change in shape and form

The placenta forms from embryonic tissue and

endometrium

Racial differences most likely arose as adaptations to different ________

environments

Eutrophication of a lake most likely is the result of

excessive concentrations of organic and inorganic nutrients.

he muscles and nervous system of the fetus become mature enough for movement to occur by the ________ month of development.

fifth

Which cardiovascular structures in the fetus shunt blood away from the fetal lungs?

foramen ovale and ductus arteriosus

Most of the energy used by humans comes from which one of the following sources?

fossil fuels

While normally one secondary oocyte ruptures from an ovarian follicle at ovulation, what will be the result if two are released and both are fertilized?

fraternal twins

Which one of the following processes tends to mix gene pools

gene flow

________ refers to random changes in allele frequency as a result of chance events.

genetic drift

Differences in populations may arise over time when physical structures in the environment, such as mountains or large bodies of water, change. These structures are referred to as

geographical barriers.

The major concerns regarding the effects of air pollution fall into the areas of smog, acid rain, destruction of the ozone layer, and

global warming

Rising atmospheric concentrations of greenhouse gasses are causing which of the following two phenomena to occur?

global warming and global climate change

Fertilization is generally considered complete when the

haploid sperm unites with the mature ovum.

Humans are classified as ________ because of our larger bodies, bigger brains, and lack of tails in relation to other primates.

hominids

The zona pellucida and corona radiata are associated with which one of the following?

human egg

Following fertilization, if a ball of embryonic cells splits into two masses before differentiation has begun, ________ twins result.

identical

Movement of individuals into or out of the population, called gene flow, impacts evolution of populations because

it leads to a redistribution of alleles.

Surface and aquifer freshwater sources hold what percent of the Earth's total water?

less than 1%

The greenhouse effect is a natural and important phenomenon because it

maintains the surface temperature on Earth.

All of the following processes are associated with embryonic development EXCEPT which one

meiosis

When a sperm cell enters a secondary oocyte, what event in the oocyte is immediately triggered?

meiosis II

RNA

molecule first formed on templates of clay in mudflats, first molecule to evolve

both DNA and RNA

molecule that directs production of proteins in modern cells

The process by which an embryo undergoes rapid changes in form and shape is called

morphogenesis.

Mesoderm gives rise to

muscle and connective tissues.

Darwin's proposal that organisms that are better suited to their environment are more likely to survive and reproduce is termed ________.

natural selection

In each local environment, populations of living organisms have evolved to possess the traits necessary to survive and reproduce. This concept is called

natural selection

The theory that individuals with certain traits are more fit for their local environment and therefore are more likely to survive and reproduce is known as

natural selection.

Which one of the following embryonic features is the forerunner of the brain and spinal cord?

neural groove

Which one of the following energy sources is NOT an alternative to fossil fuels? (A) hydroelectric power

offshore drilling

foramen

opening located between the right atrium and the left atrium

The first step in the development of living organisms was the formation of

organic molecules from gases in the atmosphere.

The first four days of human embryonic development occur in the

oviduct.

Gases such as nitrous oxide and carbon dioxide are called greenhouse gases because they

permit sunlight to enter but trap the heat energy in the atmosphere.

In the early Earth, the development of ________ created oxygen gas in the atmosphere.

photosynthesis

The evolution of ________ caused the death of many anaerobic organisms, and in their place evolved new aerobic organisms

photosynthesis

Toxicants occurring in aquatic ecosystems are highly subjected to biological magnification, meaning the

pollutants occur in higher concentrations in tissues of organisms higher up the food chain.

fossil record

preserved remains of organisms

As geographically isolated human subpopulations became adapted to different environments over time, different phenotypes resulted, causing the evolution of various human ________.

races

Which of the following pollutants is generally stored in dry locations because they remain a potential problem for thousands of years?

radioactive waste

To penetrate the zona pellucida of the ovum, the sperm

releases digestive enzymes from the acrosomal cap.

Which organ system is not functional until birth and must become fully functional immediately?

respiratory system

ductus arteriosus

shunt between the pulmonary artery and the aorta that causes most of the blood to bypass the lungs

ductus venosus

shunt that bypasses the liver

umbilical artery

structure that transports deoxygenated blood from the fetus to the placenta

umbilical vein

structure that transports oxygenated blood from the placenta to the fetus ovale

comparative anatomy

study of homologous and analogous structures

comparative embryology

study of the early development of organisms

comparative biochemistry

study of the structure of molecules to infer evolutionary relatedness of organisms

What marks the end of the pre-embryonic period and the beginning of the embryonic period?

the formation of the ectoderm and endoderm in the embryonic disk

Certain gases in the upper atmosphere allow sunlight to pass through to Earth's surface, but prevent heat from escaping. This is known as

the greenhouse effect.

A zygote forms when

the nucleus from the sperm fuses with the egg nucleus.

DnA

the self-replicating molecule of present-day cells, more stable of the two molecules

When two species contain identical or nearly identical molecules such as proteins, this suggests

the two species share a common ancestry.

Humans are classified as hominoids because

they have larger bodies and bigger brains than other primates.

Anatomical parts of the body that serve little or no function are referred to as

vestigial structures.

________ is a biomass fuel.

wood