Answer:The Cycad tree is the sporophyte.They have flagellated sperm.
Explanation:
During pollination, the contents of the megaspore divide to form many–celled gamateophyte called the endosperm and archegonium. There is a micropyle opening with a sticky fluid, which traps the wind-borne male gametophyte (microspores) which,at this time is made up of prothallus cell;an antheridial cell and a large tube cell. The trapped microspore is sucked into the archegonia chamber. Antherizoids are released, but only one penetrates each oospore and fuses with the female nucleus. The zygote is formed in the ovule and the later develops into seed.The diploid seed germinates into a new sporophyte plant and the life cycle begins again. Examples of cycad include Cycas circinalis ,Cycas celebrical and Cycas revoluta
Answer:
Active heating captures sunlight, either as heat or electricity, to augment heating systems, while passive heating captures heat from the sun as it comes into your home through windows, roofs and walls to heat objects in your home (hope that helped?)
Explanation:
Answer:
the first one air pressure
Basically the seed contains 2 parts, the testa, which is the seed coat that protects the seed and cotelydon, which is the inside of the seed, containing the radical and plumle.
for seed to germinate, we need 3 basic conditions,
warmth, it is the suitable temperature for seed germination, it can influence the activity of enzymes. providing a optimum temperature
water, to soften down the testa so that the shoot can break out from the testa
and oxygen, for aerobic respiration
.
If these conditions are absent, the seed may be in the state of dormancy. where is won't germinate until it meets the suitable conduction.
after that, the enzyme will digest the nutrient inside the seed and provide amino acid, which is necessary to seed germination. and meanwhile the aerobic respiration provides energy, so that the plumlecan shoot out, and be the shoot of the plant.
and then until it grows leaves, it'll start to complete photosynthesis, instead of using the nutrients inside the cotelydon.
Answer:
the correct option is:
a. causing contractions of the uterine smooth muscle during childbirth.
Explanation:
The question is: what is oxytocin responsible for?
a. causing contractions of the uterine smooth muscle during childbirth.
Oxytocin is responsible, being this the correct answer.
b. prevents the formation of goiters.
Thyroid hormone regulates this process.
C. Prevent the release of insulin from the pancreas.
Hormones epinephrine and norepinephrine.
d. milk production by the mammary glands.
It is prolactin who is responsible for this process
e. regulating blood calcium levels.
They are the parathormone and calcitonin.
