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photoshop1234 [79]
3 years ago
11

20. Most of today’s organisms could not have lived on Earth 3.6 billion years ago because there was no _____ in the air then.

Biology
1 answer:
Alinara [238K]3 years ago
6 0
Oxygen, mostly bacteria and they ran on glycolosis
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In the game peek-a-boo, the mother initially covers the baby. then she removes the cover and registers "surprise" at the infant'
alisha [4.7K]

Answer;

-Scaffolding

Explanation;

Scaffolding as a metaphor in teaching and learning describes the adaptive and temporary support provided by a more competent person (e.g., teacher or adult) to a less competent person (e.g., student or child). For example; mother–child interaction during the game of peekaboo.

Scaffolding is one of the several aspects of effective instruction that can be applied in the context of language learning. Although teachers might be enthusiastic about the idea of scaffolding, it must be borne in mind that scaffolding is not simply synonymous with teacher support.


4 0
3 years ago
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Mendel found out everything about genetics and we have not learned anything new about genetics in the last 160+ years. true or f
Anvisha [2.4K]

Answer:

false

Explanation:

there has been many advancements in genetics ever since Mendel's discoveries

7 0
3 years ago
When the knee is bent, the hamstring group of muscles contract. What is the insertion of this muscle group?
DIA [1.3K]

Answer:

The Knee Flexor Muscles

Explanation: The Hamstrings All three hamstring muscles originate from the ischial tuberosity and run toward the knee. The biceps femoris muscle is inserted into the head of the fibula. It can rotate the lower leg so that the foot points laterally.

5 0
3 years ago
Active and passive immunity involves all of the following except receiving mother's antibodies through breast-feeding. exposure
Bingel [31]

Explanation:

Immunity is the ability of an animal to resist infection.

There are two types of immunity in the body; INNATE OR INHERITED IMMUNITY AND ACQUIRED IMMUNITY. Inherited immunity it is the type of immunity that one is born with. It is passed from parent to offspring.

Acquired immunity is immunity to particular infections that is not inherited but has developed in the animal's life as it interacts with its environment. Acquired immunity can develop naturally in which case it is called NATURAL ACQUIRED IMMUNITY OR ARTIFICALLY.  

ACTIVE IMMUNITY is the form of acquired immunity in which the body produces its OWN antibodies against infections. While PASSIVE IMMUNITY is the form of acquired immunity in which an individual is PROTECTED AGAINST INFECTION BY RECEIVING ANTIBODIES.  

NATURAL ACQUIRED IMMUNITY

when attacked by the same pathogens again, they don't became seriously ill. this is because memory cells are able to recognise the antigens and stimulate the immune system to produce antibodies against the pathogens. This is known as NATURAL ACTIVE ACQUIRED IMMUNITY. It develops when one recovers from an infection.

During pregnancy, the mother passes antibodies across the placenta to the foetus. At birth the baby gets antibodies from the mother through breast milk. This is natural passive acquired immunity.      

3 0
2 years ago
what is one defining feature of a prokaryotic cell? cytoplasm surrounds organelles organelles are not membrane-bound membrane-bo
labwork [276]
Prokaryotic cells also have loose/free/a ring of DNA (not confined to a nucleus) and they can also sometimes have a capsule (slimy outer layer). Also they have slightly smaller ribosomes- 70s instead of 80s.
8 0
3 years ago
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