The structure seta of the sporophyte performs


Answer 1


Forms the supporting stalk.


Related Questions


If a total of 2000 kcal were consumed (250 grams of carbohydrates, 66 grams of fat, and 102 grams of protein), what percentage of energy comes from carbohydrates, fat, and protein? A. 30% carbohydrate, 50% fat, and 20% protein
B. 50% carbohydrate, 35% fat, and 15% protein
C. 20% carbohydrate, 30% fat, and 50% protein
D. 50% carbohydrate, 30% fat, and 20% protein


The correct option is D) 50% carbohydrate, 30% fat , and 20% protein

Calculation of energy percentage:

1 gram of carbohydrate and protein comprise nearest of 9 kcal while on the other hand, 1 gram of lipid contains 9 kcal.

For carbohydrate, = = 50%

For fat = 30%

For proteins = = 20%

Based on this above computation, the option D is correct.

Find out more information about the  Fat


D)50% carbohydrate, 30% fat , and 20% protien


1 gram of carbohydrate and protien contains almost 9 kcal while 1 gram of lipid contains 9 kcal.

As there is a total of 2000 Kcal. 250 g of carbohydrate will contain 1000 kcal (250 g * 4 =1000kcal). Similarly 66g of fat will contain (66*9=594kcal) .While 102 g of protiens will contain (102 * 4=408kcal). As the percentages are counted by formula Individual calories /total calories * 100. carbs contribute 50% as per the fromula 1000/2000 *100 .Similarly fat contributes 30% as per formula 594/2000 * 100 while protiens contributes 20% as per the same formula 408/2000 * 100.


Which of the following molecules get recycled during photosynthesis


Answer:NADPH and ATPExplanation:

When the light absorbs by the photosynthetic apparatus, the water molecules break down to produce essential material to continue the photosynthetic cycle as electron and H-ions. The H-ions becomes stored in thylakoid chamber and passed through the ATP synthetic machines to refill the ADP or AMP molecules. The generated electron passes through the various stages of photosynthetic series to finally produce the NADPH which also acts as energy transfer compound. At the PSI, the electron transfer to the NADP to generate NADPH.

well photosynthesis uses sunlight to split H2O and pass on an electron pair to plastoquinone (photosynthesis II) and to NADP+ -> NADPH (photosynthesis I). Also phosphorylation of ADP to ATP.. idk what they mean by recycling.. it would be H2O and CO2 that they "recycle" if anything. 

in a class of 40 students,3/4 are boys. 2/5 of the girls wear spectacles. how many girls do not wear spectacles ?​


Answer: 6 girls do not wear spectacles.

Explanation: 3/4 of 40 students are boys => 3/4 x 40 = 30. Therefore, there are 30 boys in the class.

Number of girls = 40 - 30= 10

2/5 of 10 girls wear spectacles => 2/5 x 10 =4

Therefore number of girls that do not wear spectacles is 10 - 4= 6girls


Read the scenario. Loretta has a sample that contains a mixture of different DNA molecules. She would like to separate them by size to help her determine the length of each molecule. Which technique should she use? DNA barcoding
gel electrophoresis
Sanger sequencing



gel electrophoresis


Gel electrophoresis is a technique of cell biology capable of separating molecules making them migrate from one pole of the gel, to the opposite pole through a potential difference. This technique is perfect for determining the size of the molecules, because the smaller molecules are able to migrate from one pole to the other with greater speed than the larger molecules.

With gel electrophoresis, Loretta will be able to separate DNA molecules by size, helping her to determine the length of each molecule.


☛ Sanger Sequencing ☚ **is the correct answer**



What happened to the green active site of the protein in the mutated cftr protein



The role of CFTR is to build channels on the cell surface to enable the flow of chloride (Cl-). When the  CFTR protein works properly, the balance of Cl-and fluid at the cell surface is normal. If the mutation of  CFTR protein happens the balance of Cl- and fluids is disrupted, causing mucus in various organs to  become thick and gluey. As a result, lung infections and, eventually, respiratory failure in the lungs might  occur. Mutations on the CFTR normally change single amino acids in the CFTR protein which happens  in abnormal channel breaks down soon after it is made.


The CFTR gene gives direction for producing a protein called the cystic fibrosis trans membrane  conductance regulator. This protein functions being a channel over the membrane of cells that produce  mucus, sweat, saliva, tears, and digestive enzymes.The channel transports negatively filled particles  called chloride ions into and out of cells.The transport of chloride ions improves control the movement of  water in tissues, which is essential for the creation of thin, freely flowing mucus. Mucus is a slippery  substance that greases and defends the lining of the airways, digestive system, reproductive system,  and different organs and tissues.The CFTR protein further regulates the role of other channels, such as  those that transport positively charged particles called sodium ions across cell membranes. These  channels are essential for the normal function of organs such as the lungs and pancreas.

The CFTR protein is involved in regulation of chloride and fluid transport across the cell membrane and in thin mucus development.The mutation in this CFTR protein may cause hindrance in these functions.

Further Explanation:

The cystic fibrosis transmembrane conductance regulator is the protein transcribed by the CFTR gene which acts as the channel protein across the cell membrane which is involved in the production of tears, sweat, saliva and digestive enzyme.

This channel is plays key role in the transport of the negatively charged particles known as chloride ions inside and outside of the cell. This transport regulates the water movement in the tissues and is also required for production of freely flowing, thin mucus. Mucus is little slippery substance which protects and lubricates the airways lining, digestive system and reproductive system.

The CFTR protein also controls other channels function like the one which is involved in the transport of positively charged particle such as sodium ions across the cell membrane.

Cystic fibrosis is caused because of mutation of CFTR gene which may cause either lack of formation of CFTR or malformed CFTR formation. In an individual there are two copies of CFTR gene and for that person to develop CFTR there has to be mutation in both the genes present

Learn more:

  1. Learn more about disease
  2. Learn more about CFTR
  3. Learn more about genetic code

Answer Details:

Grade: College Biology

Subject: Biology

Chapter: Diseases


Cystic fibrosis, transmembrane, conductance regulator, protein, CFTR gene, channel protein, cell membrane, digestive enzyme, negatively charged particles, chloride ions , mucus, reproductive system, mutation.


He constant, dynamic process of continual addition of new bone tissue (bone ____________ ) and removal of old bone tissue (bone ____________ ) is a process called bone ____________ . This ongoing process occurs at both the ____________ (outer) and ____________ (inner) surfaces of a bone. It is estimated that about ____________ of the adult human skeleton is replaced yearly. This process does not occur at the same rate everywhere in the skeleton. For example, the ____________ in our skeleton is replaced at a slower rate than the ____________ .


1. The right answer is bone deposition.

During the formation of osteon, osteoblasts, embryonic bone cells, deposit around them ossein which is progressively mineralized. Thus become osteocytes, these immured cells nevertheless still receive nutrients and oxygen through the fine canalicles which connect them and which also serve for the elimination of waste.

2. The right answer is bone resorption.

Osteoclasts are the cells responsible for bone resorption by attaching to the bone matrix via the development of junctions: the podosomes consist of integrins, adhesion proteins, creating a tight zone where the action of proton pump decreases the pH , and the secretion of proteolytic enzymes, which leads to the degradation of the bone matrix, and the reabsorption of its components. The gaps left after the action of osteoclasts are called "Howship Gaps". They serve in particular to detect cases of hyper-resorption when they are too numerous.

This osteoclastic activity is permanent and necessary to maintain bone strength, in synergy with the activity of osteoblasts.

Osteoclasts are present in bone tissue being resorbed.

3. The right answer is bone remodeling.

Bone remodeling is the result of precise cooperation between osteoclasts and osteoblasts. Whether in the compact or trabecular bone, the bone tissue is constantly renewed. This permanent remodeling, in which the resorption and the formation of bone tissue take place, is carried out thanks to functional units of remodeling where the osteoclasts and osteoblasts are closely associated. The bone is thus formed of millions of functional units of remodeling, mobile and progressing in the bone tissue (the osteoclasts being at the front and the osteoblasts at the back). The metabolic activities of these 2 cell populations are coupled in space and time. A remodeling cycle lasts approximately 4 months in adults, the training phase being longer than that of resorption.

4. The right answer is periosteal.

The periosteum is a set of layers of the periphery of the long bones and flat bones outside the articular surfaces and which ensure the growth in thickness. We speak of "periosteal growth in width".

Composed of a fibrous outer layer, a fibroelastic intermediate layer and an osteoblastic (non-fibrous) inner layer, this connective tissue is able to ensure the insertion of tendons and ligaments on the bone. It is a predominantly fibrous, non-oriented connective tissue.

5. The right answer is endosteal.

The endosteum is a thin layer of connective tissue lining the surface of the medullary cavity of long bones1. This layer is resorbed during long periods of malnutrition, resulting in a decrease in cortical thickness. The outer surface of a bone is also bordered by a thin layer of connective tissue very similar in morphology and function to that of the endosteum, (called periosteum).

6. The right answer is 20%.

Living structure, our skeleton is renewed each year by 20%. This "bone remodeling" is essential to maintain the mechanical and metabolic functions of our framework.

At the heart of this process are two types of cells:

* Osteoclasts responsible for destroying old bone by digging holes (resorption);

* Osteoblasts responsible for making new bone partly thanks to calcium by filling the holes (formation) "dug" by osteoclasts.

Osteoblasts and osteoclasts work together to replace calcified cartilage with true bone tissue.

The bone undergoes a constant rearrangement (the bone is continuously resorbed and rebuilt).

7. The right answer is compact bone.

The compact bone constitutes the diaphysis of the long bones and the envelope of the flat and short bones.

The compact bone or cortical bone (80-85% bone) constitutes a resistant envelope composed by the juxtaposition of cylindrical osteons of 200 to 300 μm in diameter aligned parallel to the diaphysis, each osteon is composed of concentric lamellae. The collagen fibers are oriented to impart optimal mechanical strength to the cortical tissue. Each osteon is centered by a channel called "de Havers" of 50 microns in diameter. The Havers canals are interconnected by transverse channels called "Volkmann". Each channel is centered by an innervated vessel that communicates with both the periosteal vasculature and the vessels of the marrow.

8. The right answer is spongy bone.

Spongy bone or trabecular bone constitutes the epiphyses and metaphyses of long bones and the interior of flat bones and short bones. It consists of a network of plates and anastomosed cylinders. With age, the spans are rather cylinders. Each plate has the overall shape of a parallelepiped. The three-dimensional organization of these bone plates together is the trabecular architecture which has an important role in the mechanical strength of the bone. The orientation of the spans depends on the lines of mechanical forces to which the bone is subjected because the cells that manufacture them (the osteoblasts) have the capacity to perceive these mechanical forces.

He constant, dynamic process of continual addition of new bone tissue is bone deposition and removal of old bone tissue is bone resorption is a process called bone replacement. This ongoing process occurs at both the periosteal(outer) and endosteal (inner) surfaces of a bone. It is estimated that about ten percent of the adult human skeleton is replaced yearly. This process does not occur at the same rate everywhere in the skeleton. For example, the compact bone in our skeleton is replaced at a slower rate than the spongy bone.


- Deposition: The process of deposition or disappearing of bones.

- Tissue: Is a multicellular organism in the body of living organism.

- Resorption: Is the dissolution of a tissue in the body.

- Periosteal: It is the  inner layer that is self ability of forming a bone in the body.

- Endosteal: It is the membrane lining of cavity of the bones in the human body.

- Compact Bone: The compressed noncancellous division of bone.

- Spongy Bone: It is the bone in which the spicules make a latticework.


Relate cause and effect how does crossing-over increase variation in genes?


The zygote will have the complete or diploid number of chromosomes, which is 46. The two ways wherein meiosis increases genetic diversity in a species are crossing over and independent assortment of homologous chromosomes.

Tom is scheduled to have surgery next week in order to remove a large tumor from his frontal lobe. after his procedure, tom is most likely going to have difficulty with ______.


After his procedure, Tom is most likely going to have difficulty with movement and language.

What is the frontal lobe?

The frontal lobe is a brain region found in the most anterior part of the cerebrum organ (i.e.,m the brain)

  • This brain region (frontal lobe) has functions mainly associated with complex movements and language.

In conclusion, after his procedure, Tom is most likely going to have difficulty with movement and language.

Learn more about the front lobe here:


Could you give me your answers so that I can better answer the question?

Question 2: What two substances make the backbone of the DNA molecule? *
Adenine and Thymine

Cytosine and Guanine

Sugar and Phosphate

Adenine and Uracil


cytosine and guanine is the correct answer

Random Questions