1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
elixir [45]
3 years ago
9

At the end of which period did nearly 3/4 of all species of life on earth go extinct in a very short time interval?

Biology
1 answer:
alukav5142 [94]3 years ago
7 0

There have been five mass extinction events throughout Earth's history:

The first great mass extinction event took place at the end of the Ordovician, when according to the fossil record, 60% of all genera of both terrestrial and marine life worldwide were exterminated.  

360 million years ago in the Late Devonian period, the environment that had clearly nurtured reefs for at least 13 million years turned hostile and the world plunged into the second mass extinction event.

The fossil record of the end Permian mass extinction reveals a staggering loss of life: perhaps 80–95% of all marine species went extinct. Reefs didn't reappear for about 10 million years, the greatest hiatus in reef building in all of Earth history.  

The end Triassic mass extinction is estimated to have claimed about half of all marine invertebrates. Around 80% of all land quadrupeds also went extinct.

The end Cretaceous mass extinction 65 million years ago is famously associated with the demise of the dinosaurs. Virtually no large land animals survived. Plants were also greatly affected while tropical marine life was decimated. Global temperature was 6 to 14°C warmer than present with sea levels over 300 metres higher than current levels. At this time, the oceans flooded up to 40% of the continents.

You might be interested in
What happens to gas exchange in a low oxygen environment?.
emmasim [6.3K]

Gas exchange takes place in the millions of alveoli in the lungs and the capillaries that envelop them. As shown below, inhaled oxygen moves from the alveoli to the blood in the capillaries,
8 0
2 years ago
I’m stuck! Please help
prisoha [69]
Human Flora

Lesson Transcript

Instructor: Rebecca Gillaspy
Dr. Gillaspy has taught health science at University of Phoenix and Ashford University and has a degree from Palmer College of Chiropractic.

The amount of blood being pumped through your body changes constantly due to the demands of daily life. In this lesson, you will learn how your body adjusts the heart rate and stroke volume to increase or decrease blood flow.

Cardiac Output

The volume of blood your heart pumps per minute, known as your cardiac output, varies with the demands you put on your body. We previously learned that the cardiac output (CO) is calculated by multiplying the number of heartbeats per minute (which is your heart rate, or HR) times the volume of blood pumped out of the heart with each heartbeat (which is your stroke volume, or SV). So:
cardiac output (CO) = heart rate (HR) x stroke volume (SV)
The cardiac output of your heart is a constantly changing amount that adjusts to any physical or emotional demands you put on your body. In this lesson, we will look at some of the factors that influence your heart rate and stroke volume.

6 0
3 years ago
The growth of plant seedlings is usually
zhenek [66]

Answer:

The correct answer is - A. phototropic and gravitropic.

Explanation:

A plant seedling grows usually two-direction shoots or stems towards light and roots towards the soil or in the direction of gravity. The movement of the plant toward a specific stimulus or effect parts is called tropism and different parts move in a different direction.

The movement of the roots of the plant is usually towards the direction of soil or gravity and this is called gravitropic. The shoot or stem grows from the seedling towards the direction of light and it is called phototropic.

7 0
3 years ago
EASY QUESTION:<br> What are two suggestions you would make about ways to conserve water?
olganol [36]
Turn off the water when it is not needed; for example, turn off the water when you brush your teeth, turn off the water when you’re scrubbing your body and hair in the shower with soap (only turn it back on when you want to rinse).

To summarize: TURN OFF THE WATER (when it’s not needed) :)
6 0
3 years ago
Need help ASAP please and thank you !!!
irakobra [83]

Answer: i believe it’s A and C

Explanation: i took biology and remember these lessons

3 0
2 years ago
Read 2 more answers
Other questions:
  • Biceps are made mostly of _____. neurons, squamous epithelial, cells, skeletal muscle, smooth muscle
    12·2 answers
  • Why is nitrogen so important to plants
    12·2 answers
  • Which is not an example of an earth system cycle?
    9·2 answers
  • Genetic drift and gene flow have what in common?
    14·1 answer
  • Recombinant DNA technology involves which sequence of steps?
    11·2 answers
  • One main difference between a pine tree and an arctic fox is..?
    15·2 answers
  • What is the product (end result) of translation?
    13·2 answers
  • You encounter someone who has never heard of evolution, and they ask you about a population of ducks that live in their grandmot
    13·1 answer
  • Define dark reaction​
    10·1 answer
  • Bacteria are used in photosynthesis.<br><br> True<br> False
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!