Coronary artery.....are the arteries that provide blood to the wall of heart !
Great question! Let me first talk about how sedimentary rocks are formed. Sedimentary rocks are formed when when existing rocks are broken down in sediment. Now, let me explain what they are. Sedimentary rocks are rocks that have been weathered into rock fragments or pieces.
Answer:
This question is incomplete as the term to match with the level of organisation is not included, the terms are;
circulatory system
cardiac muscle
heart
human body
The ANSWER is:
Organ = heart
Organ system = circulatory system
Tissue: cardiac muscle
Explanation:
The level of organization of multicellular organisms is made up of cell, tissue, organ, organ system and eventually organism.
- The tissue is composed of several cell, which are basic units of any living organism. Cells that perform similar function come together to form the tissue. Example is the CARDIAC MUSCLE in this question, which is a muscular tissue made up of cells called myocardiocytes.
- Organs are structures formed as a result of collection of tissues with similar function. For example, the HEART is a circulatory organ made up of cardiac tissues, connective tissues etc.
- Organ systems is made up of organs that perform the same function in a living organism. In the case of the CIRCULATORY SYSTEM, it is made up of organs such as heart, blood vessels, lungs etc.
Answer: Magnolia is a large genus of about 210 flowering plant species in the subfamily Magnolioideae of the family Magnoliaceae. It is named after French botanist Pierre Magnol. Magnolia is an ancient genus. Appearing before bees did, the flowers are theorized to have evolved to encourage pollination by beetles. To avoid damage from pollinating beetles, the carpels of Magnolia flowers are extremely tough. Fossilized specimens of M. acuminata have been found dating to 20 million years ago, and of plants identifiably belonging to the Magnoliaceae date to 95 million years ago. Another aspect of Magnolia considered to represent an ancestral state is that the flower bud is enclosed in a bract rather than in sepals; the perianth parts are undifferentiated and called tepals rather than distinct sepals and petals. Magnolia shares the tepal characteristic with several other flowering plants near the base of the flowering plant lineage such as Amborella and Nymphaea.
Explanation:
Answer:
a. + glucose, + lactose = On
b. - glucose, - lactose = Off
c. + glucose, - lactose = Off
d. - glucose, + lactose = On
Explanation:
Lac operon has both types of control, repressible and inducible.
Whenever glucose level is low in the cell, an enzyme known as adenylyl cyclase raises the level of cAMP which forms a dimer with CRP protein and they both act as activator of lac operon and cause expression.
Apart from this, when lactose is present in the cell, β-galactosidase enzyme metabolizes lactose to form allolactose which causes allosteric repulsion in the lac repressor and causes its removal from the operator. As soon as repressor is removed lac operon gets activated.
In wild type lac operons, the expression of lac operon occurs when glucose level is low in the cell and lactose is present but in this mutant presence or absence of glucose will not make a difference because CRP will bind Plac promoter independent of cAMP level i.e. activator CRP will work even in high glucose concentration. If lactose is present then lac operon will always express so in option 'a & d' lac operon will express but in option 'b & c' it will not express.